Sorry your browser is not supported!

I have been tring to make my alien move right then when the right hand alien hits the edge of the screen they start going in the opposite direction until the left hand lien hit the side etc.
This is my source

Rem Project: Space Invaders
Rem Created: 16/05/2004 11:04:38

Rem ***** Main Source File *****

Set Display Mode 800,600,32
Sync On : Sync Rate 100 : Hide Mouse

PlayerX = 400-10
PlayerY = 550
BulletX = PlayerX+21
BulletY = 550

For t=1 to 1
   rem Load image
   Load Image "images\ship1.png",1
   Load Image "images\bluenemy.png",2
   Load Image "images\grnenemy.png",3
   Load Image "images\purpenemy.png",4
   Load Image "images\bottomleft+right.png",5
   Load Image "images\bullete.png",6
   Load Image "images\bulletp.png",7
   Load Image "images\ship2.png",8
   rem load Theme Sound
   Load Sound "Music\Space Invaders Background.WAV",1
   rem Set the sound speed
   Set Sound Speed 1,35000
   rem Loop Theme Sound
   Loop Sound 1
next t

For Enemy=1 to 10
	Sprite Enemy+2,Enemy*67,100,2
Next Enemy

Do
   If Sprite X(3)<=0 Or Sprite X(12)=>754 
   	For Enemy=1 to 10
   		BlueEnemyX=Sprite X(Enemy+2)
   		BlueEnemyX=BlueEnemyX+3
   		Sprite Enemy+2,BlueEnemyX,100,2
   	Next Enemy
   endif
   If Sprite X(3)<=0 Or Sprite X(12)=>754 
    	For Enemy=1 to 10
   		BlueEnemyX=Sprite X(Enemy+2)
   		BlueEnemyX=BlueEnemyX-3
   		Sprite Enemy+2,BlueEnemyX,100,2
   	Next Enemy
   endif
   rem Exit the program
   If Escapekey()=1 Then End
   rem Create/Repoition Player Ship
   Sprite 1,PlayerX,PlayerY,1
   rem Move Player Ship
   If Leftkey()=1 And PlayerX>=0 Then PlayerX = PlayerX-3
   If Rightkey()=1 And PlayerX<=750 Then playerX = PlayerX+3
   If Spacekey()=1 Then Sprite 2,BulletX,BulletY,7 : Sprite 2,BulletX,BulletY,7
   If Sprite Exist(2)=1 Then BulletY=BulletY-3 : Sprite 2,BulletX,BulletY,7
   If BulletY<=0 Then Delete Sprite 2 : BulletY=550
   If Sprite Exist(2)=0 Then BulletX = PlayerX+21
   Sync
Loop

Rem Project: Space Invaders
Rem Created: 16/05/2004 11:04:38

Rem ***** Main Source File *****

Set Display Mode 800,600,32
Sync On : Sync Rate 100 : Hide Mouse

PlayerX = 400-10
PlayerY = 550
BulletX = PlayerX+21
BulletY = 550

For t=1 to 1
   rem Load image
   Load Image "images\ship1.png",1
   Load Image "images\bluenemy.png",2
   Load Image "images\grnenemy.png",3
   Load Image "images\purpenemy.png",4
   Load Image "images\bottomleft+right.png",5
   Load Image "images\bullete.png",6
   Load Image "images\bulletp.png",7
   Load Image "images\ship2.png",8
   rem load Theme Sound
   Load Sound "Music\Space Invaders Background.WAV",1
   rem Set the sound speed
   Set Sound Speed 1,35000
   rem Loop Theme Sound
   Loop Sound 1
next t

For Enemy=1 to 10
	Sprite Enemy+2,Enemy*67,100,2
Next Enemy

Do
   If Sprite X(3)<=0 Or Sprite X(12)=>754 
   	For Enemy=1 to 10
   		BlueEnemyX=Sprite X(Enemy+2)
   		BlueEnemyX=BlueEnemyX+3
   		Sprite Enemy+2,BlueEnemyX,100,2
   	Next Enemy
   endif
   If Sprite X(3)<=0 Or Sprite X(12)=>754 
    	For Enemy=1 to 10
   		BlueEnemyX=Sprite X(Enemy+2)
   		BlueEnemyX=BlueEnemyX-3
   		Sprite Enemy+2,BlueEnemyX,100,2
   	Next Enemy
   endif
   rem Exit the program
   If Escapekey()=1 Then End
   rem Create/Repoition Player Ship
   Sprite 1,PlayerX,PlayerY,1
   rem Move Player Ship
   If Leftkey()=1 And PlayerX>=0 Then PlayerX = PlayerX-3
   If Rightkey()=1 And PlayerX<=750 Then playerX = PlayerX+3
   If Spacekey()=1 Then Sprite 2,BulletX,BulletY,7 : Sprite 2,BulletX,BulletY,7
   If Sprite Exist(2)=1 Then BulletY=BulletY-3 : Sprite 2,BulletX,BulletY,7
   If BulletY<=0 Then Delete Sprite 2 : BulletY=550
   If Sprite Exist(2)=0 Then BulletX = PlayerX+21
   Sync
Loop

Could someone tell me what i am doing wrong?
thanx

Back to top

Profile PM Email Website

GameMaker Jason

21

Years of Service

User Offline

Joined: 22nd Nov 2003

Location: UK

Posted: 18th May 2004 21:00

I've have done the alein movement but have been tring to make the aliens disapear when the bullet hits them but i get an error say that prite does not exist what is wrong with this code?

Set Display Mode 800,600,32
Sync On : Sync Rate 100 : Hide Mouse

PlayerX = 400-10
PlayerY = 550
BulletX = PlayerX+21
BulletY = 550

For t=1 to 1
   rem Load image
   Load Image "images\ship1.png",1
   Load Image "images\bluenemy.png",2
   Load Image "images\grnenemy.png",3
   Load Image "images\purpenemy.png",4
   Load Image "images\bottomleft+right.png",5
   Load Image "images\bullete.png",6
   Load Image "images\bulletp.png",7
   Load Image "images\ship2.png",8
   rem load Theme Sound
   Load Sound "Music\Space Invaders Background.WAV",1
   rem Set the sound speed
   Set Sound Speed 1,35000
   rem Loop Theme Sound
   Loop Sound 1
next t

For Enemy=1 to 10
	Sprite Enemy+2,Enemy*67,100,2
Next Enemy

For Enemy=1 to 10
	Sprite Enemy+12,Enemy*67,200,3
Next Enemy

For Enemy=1 to 10
	Sprite Enemy+22,Enemy*67,300,4
Next Enemy

Do
	For Enemy=1 to 10
		BlueEnemyX=Sprite X(Enemy+2)
		If BlueEnemyDir=1
			Sprite Enemy+2,BlueEnemyX+2,100,2
		Endif
		If BlueEnemyDir=0
			Sprite Enemy+2,BlueEnemyX-2,100,2
		Endif
		If Sprite Visible(2) And Sprite Hit(2,Enemy+2)
			Hide Sprite Enemy+2
		endif
	Next Enemy
	For Enemy=1 to 10
		GrnEnemyX=Sprite X(Enemy+12)
		If GrnEnemyDir=1
			Sprite Enemy+12,GrnEnemyX+2,200,3
		Endif
		If GrnEnemyDir=0
			Sprite Enemy+12,GrnEnemyX-2,200,3
		Endif
		If Sprite Visible(2) And Sprite Hit(2,Enemy+12)
			Hide Sprite Enemy+12
		endif
	Next Enemy
	For Enemy=1 to 10
		PurpEnemyX=Sprite X(Enemy+22)
		If PurpEnemyDir=1
			Sprite Enemy+22,PurpEnemyX+2,300,4
		Endif
		If PurpEnemyDir=0
			Sprite Enemy+22,PurpEnemyX-2,300,4
		Endif
		If Sprite Visible(2) And Sprite Hit(2,Enemy+22)
			Hide Sprite Enemy+22
		endif
	Next Enemy
   rem Exit the program
   If Escapekey()=1 Then End
   rem Create/Repoition Player Ship
   Sprite 1,PlayerX,PlayerY,1
   rem Move Player Ship
   If Leftkey()=1 And PlayerX>=0 Then PlayerX = PlayerX-3
   If Rightkey()=1 And PlayerX<=750 Then playerX = PlayerX+3
   If Spacekey()=1 Then Sprite 2,BulletX,BulletY,7 : Sprite 2,BulletX,BulletY,7
   If Sprite Visible(2)=1 Then BulletY=BulletY-3 : Sprite 2,BulletX,BulletY,7
   If BulletY<=0
   	Hide Sprite 2
   	BulletY=550
   Endif
   If Sprite Exist(2)=0 Then BulletX = PlayerX+21
   For Enemy=1 to 10
   	If Sprite X(Enemy+2)<=0
   		BlueEnemyDir=1
   	endif
   	If Sprite X(Enemy+2)>=756
   		BlueEnemyDir=0
   	endif
   next enemy
   For Enemy=1 to 10
   	If Sprite X(Enemy+12)<=0
   		GrnEnemyDir=1
   	endif
   	If Sprite X(Enemy+12)>=756
   		GrnEnemyDir=0
   	endif
   next enemy
   For Enemy=1 to 10
   	If Sprite X(Enemy+22)<=0
   		PurpEnemyDir=1
   	endif
   	If Sprite X(Enemy+22)>=756
   		PurpEnemyDir=0
   	endif
   next enemy
   Sync
Loop

Set Display Mode 800,600,32
Sync On : Sync Rate 100 : Hide Mouse

PlayerX = 400-10
PlayerY = 550
BulletX = PlayerX+21
BulletY = 550

For t=1 to 1
   rem Load image
   Load Image "images\ship1.png",1
   Load Image "images\bluenemy.png",2
   Load Image "images\grnenemy.png",3
   Load Image "images\purpenemy.png",4
   Load Image "images\bottomleft+right.png",5
   Load Image "images\bullete.png",6
   Load Image "images\bulletp.png",7
   Load Image "images\ship2.png",8
   rem load Theme Sound
   Load Sound "Music\Space Invaders Background.WAV",1
   rem Set the sound speed
   Set Sound Speed 1,35000
   rem Loop Theme Sound
   Loop Sound 1
next t

For Enemy=1 to 10
	Sprite Enemy+2,Enemy*67,100,2
Next Enemy

For Enemy=1 to 10
	Sprite Enemy+12,Enemy*67,200,3
Next Enemy

For Enemy=1 to 10
	Sprite Enemy+22,Enemy*67,300,4
Next Enemy

Do
	For Enemy=1 to 10
		BlueEnemyX=Sprite X(Enemy+2)
		If BlueEnemyDir=1
			Sprite Enemy+2,BlueEnemyX+2,100,2
		Endif
		If BlueEnemyDir=0
			Sprite Enemy+2,BlueEnemyX-2,100,2
		Endif
		If Sprite Visible(2) And Sprite Hit(2,Enemy+2)
			Hide Sprite Enemy+2
		endif
	Next Enemy
	For Enemy=1 to 10
		GrnEnemyX=Sprite X(Enemy+12)
		If GrnEnemyDir=1
			Sprite Enemy+12,GrnEnemyX+2,200,3
		Endif
		If GrnEnemyDir=0
			Sprite Enemy+12,GrnEnemyX-2,200,3
		Endif
		If Sprite Visible(2) And Sprite Hit(2,Enemy+12)
			Hide Sprite Enemy+12
		endif
	Next Enemy
	For Enemy=1 to 10
		PurpEnemyX=Sprite X(Enemy+22)
		If PurpEnemyDir=1
			Sprite Enemy+22,PurpEnemyX+2,300,4
		Endif
		If PurpEnemyDir=0
			Sprite Enemy+22,PurpEnemyX-2,300,4
		Endif
		If Sprite Visible(2) And Sprite Hit(2,Enemy+22)
			Hide Sprite Enemy+22
		endif
	Next Enemy
   rem Exit the program
   If Escapekey()=1 Then End
   rem Create/Repoition Player Ship
   Sprite 1,PlayerX,PlayerY,1
   rem Move Player Ship
   If Leftkey()=1 And PlayerX>=0 Then PlayerX = PlayerX-3
   If Rightkey()=1 And PlayerX<=750 Then playerX = PlayerX+3
   If Spacekey()=1 Then Sprite 2,BulletX,BulletY,7 : Sprite 2,BulletX,BulletY,7
   If Sprite Visible(2)=1 Then BulletY=BulletY-3 : Sprite 2,BulletX,BulletY,7
   If BulletY<=0
   	Hide Sprite 2
   	BulletY=550
   Endif
   If Sprite Exist(2)=0 Then BulletX = PlayerX+21
   For Enemy=1 to 10
   	If Sprite X(Enemy+2)<=0
   		BlueEnemyDir=1
   	endif
   	If Sprite X(Enemy+2)>=756
   		BlueEnemyDir=0
   	endif
   next enemy
   For Enemy=1 to 10
   	If Sprite X(Enemy+12)<=0
   		GrnEnemyDir=1
   	endif
   	If Sprite X(Enemy+12)>=756
   		GrnEnemyDir=0
   	endif
   next enemy
   For Enemy=1 to 10
   	If Sprite X(Enemy+22)<=0
   		PurpEnemyDir=1
   	endif
   	If Sprite X(Enemy+22)>=756
   		PurpEnemyDir=0
   	endif
   next enemy
   Sync
Loop

thanx to anyone who helps

Back to top

Profile PM Email Website

Lampton Worm

22

Years of Service

User Offline

Joined: 4th Sep 2002

Location: United Kingdom

Posted: 19th May 2004 01:45

Hi,

The message is right, you haven't created Sprite 2 anywhere.

As a sanity check, add this before your main do loop...

do
for i=1 to 80
   text 0,i*10,str$(i)+":"+str$(sprite exist(i))
next i
sync
loop

Look at number 2...not there! Remove my code, and add "sprite 2,0,0,1" before you do loop, run the program and it works. Well, the firing needs sorted out, but a bullet fires and zaps through a line of invaders.

Hope it helps,
Cheers.

Back to top

Profile PM Website

GameMaker Jason

21

Years of Service

User Offline

Joined: 22nd Nov 2003

Location: UK

Posted: 19th May 2004 20:08

I'm trying to use the stary background tut(memblocks) that TGC have on there site but i don't see stars at the bottom of the screen.

Here's my code:

Rem Project: Space Invaders
Rem Created: 16/05/2004 11:04:38

Rem ***** Main Source File *****

Rem Set the screen size and sync rate
Set Display Mode 800,600,32
Sync On : Sync Rate 100 : Hide Mouse

Rem Define Variables
PlayerX = 400-10
PlayerY = 550
BulletX = PlayerX+21
BulletY = 550
EnemyY=100
starquantity = 11000
starlayers = 15
speedfactor# = 0.90

Rem Type for the move background
type starfield

X AS FLOAT
   Y AS FLOAT
   Z AS INTEGER
   speed AS FLOAT
   color AS DWORD

endtype

Rem Array of stars
dim stars(starquantity) as starfield

rem Create the location of the stars
for s=0 to starquantity

stars(s).x = rnd(800)
   stars(s).y = rnd(600)
   stars(s).z = int(s/(starquantity/starlayers))+1
   stars(s).speed = stars(s).z * speedfactor#
   temp_col = (255/starlayers) * stars(s).z
   stars(s).color = rgb(rnd(255),rnd(255),rnd(255))

next s

Rem our memblock - this is calculated from the following: screen X * screen Y * 4 (bytes per pixel)
make memblock 1,1920000
mem_loc AS DWORD
mem_loc = get memblock ptr(1)

Rem Load media in loop
For t=1 to 1
   rem Load image
   Load Image "images\ship1.png",1
   Load Image "images\bluenemy.png",2
   Load Image "images\grnenemy.png",3
   Load Image "images\purpenemy.png",4
   Load Image "images\bottomleft+right.png",5
   Load Image "images\bullete.png",6
   Load Image "images\bulletp.png",7
   Load Image "images\ship2.png",8
   rem load Theme Sound
   Load Sound "Music\Space Invaders Background.WAV",1
   rem Set the sound speed
   Set Sound Speed 1,35000
   rem Loop Theme Sound
   Loop Sound 1
next t

Rem Draw Blue Enemies
For Enemy=1 to 10
	Sprite Enemy+2,Enemy*67,100,2
Next Enemy

Rem Draw Green Enemies
For Enemy=1 to 10
	Sprite Enemy+12,Enemy*67,200,3
Next Enemy

Rem Draw Purple Enemies
For Enemy=1 to 10
	Sprite Enemy+22,Enemy*67,300,4
Next Enemy

Rem Create and hide bullet for use in game
Sprite 2,0,0,7
Hide Sprite 2

Rem main Loop (engine)
Do
	Rem Update the Blue Enemies position
	For Enemy=1 to 10
		BlueEnemyX=Sprite X(Enemy+2)
		If BlueEnemyDir=1
			Sprite Enemy+2,BlueEnemyX+1.5,EnemyY,2
		Endif
		If BlueEnemyDir=0
			Sprite Enemy+2,BlueEnemyX-1.5,EnemyY,2
		Endif
		If Sprite Visible(2)=1 And Sprite Visible(Enemy+2)=1 And Sprite Hit(2,Enemy+2)
			Hide Sprite Enemy+2
			BulletY=550
			Hide Sprite 2
		endif
	Next Enemy
	Rem Update the Green Enemies position
	For Enemy=1 to 10
		GrnEnemyX=Sprite X(Enemy+12)
		If GrnEnemyDir=1
			Sprite Enemy+12,GrnEnemyX+1.5,EnemyY+100,3
		Endif
		If GrnEnemyDir=0
			Sprite Enemy+12,GrnEnemyX-1.5,EnemyY+100,3
		Endif
		If Sprite Visible(2)=1 And Sprite Visible(Enemy+12)=1 And Sprite Hit(2,Enemy+12)
			Hide Sprite Enemy+12
			BulletY=550
			Hide Sprite 2
		endif
	Next Enemy
	Rem Update the Purple Enemies position
	For Enemy=1 to 10
		PurpEnemyX=Sprite X(Enemy+22)
		If PurpEnemyDir=1
			Sprite Enemy+22,PurpEnemyX+1.5,EnemyY+200,4
		Endif
		If PurpEnemyDir=0
			Sprite Enemy+22,PurpEnemyX-1.5,EnemyY+200,4
		Endif
		If Sprite Visible(2)=1 And Sprite Visible(Enemy+22)=1 And Sprite Hit(2,Enemy+22)
			Hide Sprite Enemy+22
			BulletY=550
			Hide Sprite 2
		endif
	Next Enemy
   rem Exit the program
   If Escapekey()=1 Then End
   rem Create/Repoition Player Ship
   Sprite 1,PlayerX,PlayerY,1
   rem Move Player Ship
   If Leftkey()=1 And PlayerX>=0 Then PlayerX = PlayerX-3
   If Rightkey()=1 And PlayerX<=750 Then playerX = PlayerX+3
   rem Release bullet from ship
   If Spacekey()=1 Then Show Sprite 2 : Sprite 2,BulletX,BulletY,7 : Sprite 2,BulletX,BulletY,7
   If Sprite Visible(2)=1 Then BulletY=BulletY-3 : Sprite 2,BulletX,BulletY,7
   If BulletY<=0
   	Hide Sprite 2
   	BulletY=550
   Endif
   Rem Update Bullet X when bullet is hidden
   If Sprite Visible(2)=0
   	BulletX=PlayerX+21
   endif
   Rem Change the directional flag if Blue enemies reach edge of screen
   For Enemy=1 to 10
   	If Sprite X(Enemy+2)<=0 And Sprite Visible(Enemy+2)=1
   		BlueEnemyDir=1
   	endif
   	If Sprite X(Enemy+2)>=756 And Sprite Visible(Enemy+2)=1
   		BlueEnemyDir=0
   	endif
   next enemy
   Rem Change the directional flag if Green enemies reach edge of screen
   For Enemy=1 to 10
   	If Sprite X(Enemy+12)<=0 And Sprite Visible(Enemy+12)=1
   		GrnEnemyDir=1
   	endif
   	If Sprite X(Enemy+12)>=756 And Sprite Visible(Enemy+12)=1
   		GrnEnemyDir=0
   	endif
   next enemy
   Rem Change the directional flag if Purple enemies reach edge of screen
   For Enemy=1 to 10
   	If Sprite X(Enemy+22)<=0 And Sprite Visible(Enemy+22)=1
   		PurpEnemyDir=1
   	endif
   	If Sprite X(Enemy+22)>=756 And Sprite Visible(Enemy+22)=1
   		PurpEnemyDir=0
   	endif
   next enemy
   Rem When enemies reach edge of screen increase Y variable so enemies go down
   For Enemy=1 to 30
   	If Sprite X(Enemy+2)>=756 And Sprite Visible(Enemy+2)=1
   		EnemyY=EnemyY+2
   	endif
   	If Sprite X(Enemy+2)<=0 And Sprite Visible(Enemy+2)=1
			EnemyY=EnemyY+2
		Endif
   next enemy
   Rem our CLS equivalent
   fill memory mem_loc, 0, 1920000

for s=0 to starquantity

sx# = stars(s).x

Rem works out where in memory to plot our dot!
      mem_y = int(stars(s).y)*(800*4)
      mem_x = (int(sx#)*4)
      mem_location = mem_x + mem_y

Rem plots
      if mem_location > 1 and mem_location < 1920000
         write memblock dword 1, mem_location, stars(s).color
      endif

Rem moves the star
      sx# = sx# - stars(s).speed
      if sx# < 0 then sx# = 800
      stars(s).x = sx#

next s

Rem This copies the pixel data from memory to the screen
   lock pixels
   copy memory get pixels pointer(), mem_loc, 1920000
   unlock pixels
   Rem refresh screen
   Sync
Loop

Rem Project: Space Invaders
Rem Created: 16/05/2004 11:04:38

Rem ***** Main Source File *****

Rem Set the screen size and sync rate
Set Display Mode 800,600,32
Sync On : Sync Rate 100 : Hide Mouse

Rem Define Variables
PlayerX = 400-10
PlayerY = 550
BulletX = PlayerX+21
BulletY = 550
EnemyY=100
starquantity = 11000
starlayers = 15
speedfactor# = 0.90

Rem Type for the move background
type starfield

   X AS FLOAT
   Y AS FLOAT
   Z AS INTEGER
   speed AS FLOAT
   color AS DWORD

endtype

Rem Array of stars
dim stars(starquantity) as starfield

rem Create the location of the stars
for s=0 to starquantity

   stars(s).x = rnd(800)
   stars(s).y = rnd(600)
   stars(s).z = int(s/(starquantity/starlayers))+1
   stars(s).speed = stars(s).z * speedfactor#
   temp_col = (255/starlayers) * stars(s).z
   stars(s).color = rgb(rnd(255),rnd(255),rnd(255))

next s

Rem our memblock - this is calculated from the following: screen X * screen Y * 4 (bytes per pixel)
make memblock 1,1920000
mem_loc AS DWORD
mem_loc = get memblock ptr(1)

Rem Load media in loop
For t=1 to 1
   rem Load image
   Load Image "images\ship1.png",1
   Load Image "images\bluenemy.png",2
   Load Image "images\grnenemy.png",3
   Load Image "images\purpenemy.png",4
   Load Image "images\bottomleft+right.png",5
   Load Image "images\bullete.png",6
   Load Image "images\bulletp.png",7
   Load Image "images\ship2.png",8
   rem load Theme Sound
   Load Sound "Music\Space Invaders Background.WAV",1
   rem Set the sound speed
   Set Sound Speed 1,35000
   rem Loop Theme Sound
   Loop Sound 1
next t

Rem Draw Blue Enemies
For Enemy=1 to 10
	Sprite Enemy+2,Enemy*67,100,2
Next Enemy

Rem Draw Green Enemies
For Enemy=1 to 10
	Sprite Enemy+12,Enemy*67,200,3
Next Enemy

Rem Draw Purple Enemies
For Enemy=1 to 10
	Sprite Enemy+22,Enemy*67,300,4
Next Enemy

Rem Create and hide bullet for use in game
Sprite 2,0,0,7
Hide Sprite 2

Rem main Loop (engine)
Do
	Rem Update the Blue Enemies position
	For Enemy=1 to 10
		BlueEnemyX=Sprite X(Enemy+2)
		If BlueEnemyDir=1
			Sprite Enemy+2,BlueEnemyX+1.5,EnemyY,2
		Endif
		If BlueEnemyDir=0
			Sprite Enemy+2,BlueEnemyX-1.5,EnemyY,2
		Endif
		If Sprite Visible(2)=1 And Sprite Visible(Enemy+2)=1 And Sprite Hit(2,Enemy+2)
			Hide Sprite Enemy+2
			BulletY=550
			Hide Sprite 2
		endif
	Next Enemy
	Rem Update the Green Enemies position
	For Enemy=1 to 10
		GrnEnemyX=Sprite X(Enemy+12)
		If GrnEnemyDir=1
			Sprite Enemy+12,GrnEnemyX+1.5,EnemyY+100,3
		Endif
		If GrnEnemyDir=0
			Sprite Enemy+12,GrnEnemyX-1.5,EnemyY+100,3
		Endif
		If Sprite Visible(2)=1 And Sprite Visible(Enemy+12)=1 And Sprite Hit(2,Enemy+12)
			Hide Sprite Enemy+12
			BulletY=550
			Hide Sprite 2
		endif
	Next Enemy
	Rem Update the Purple Enemies position
	For Enemy=1 to 10
		PurpEnemyX=Sprite X(Enemy+22)
		If PurpEnemyDir=1
			Sprite Enemy+22,PurpEnemyX+1.5,EnemyY+200,4
		Endif
		If PurpEnemyDir=0
			Sprite Enemy+22,PurpEnemyX-1.5,EnemyY+200,4
		Endif
		If Sprite Visible(2)=1 And Sprite Visible(Enemy+22)=1 And Sprite Hit(2,Enemy+22)
			Hide Sprite Enemy+22
			BulletY=550
			Hide Sprite 2
		endif
	Next Enemy
   rem Exit the program
   If Escapekey()=1 Then End
   rem Create/Repoition Player Ship
   Sprite 1,PlayerX,PlayerY,1
   rem Move Player Ship
   If Leftkey()=1 And PlayerX>=0 Then PlayerX = PlayerX-3
   If Rightkey()=1 And PlayerX<=750 Then playerX = PlayerX+3
   rem Release bullet from ship
   If Spacekey()=1 Then Show Sprite 2 : Sprite 2,BulletX,BulletY,7 : Sprite 2,BulletX,BulletY,7
   If Sprite Visible(2)=1 Then BulletY=BulletY-3 : Sprite 2,BulletX,BulletY,7
   If BulletY<=0
   	Hide Sprite 2
   	BulletY=550
   Endif
   Rem Update Bullet X when bullet is hidden
   If Sprite Visible(2)=0
   	BulletX=PlayerX+21
   endif
   Rem Change the directional flag if Blue enemies reach edge of screen
   For Enemy=1 to 10
   	If Sprite X(Enemy+2)<=0 And Sprite Visible(Enemy+2)=1
   		BlueEnemyDir=1
   	endif
   	If Sprite X(Enemy+2)>=756 And Sprite Visible(Enemy+2)=1
   		BlueEnemyDir=0
   	endif
   next enemy
   Rem Change the directional flag if Green enemies reach edge of screen
   For Enemy=1 to 10
   	If Sprite X(Enemy+12)<=0 And Sprite Visible(Enemy+12)=1
   		GrnEnemyDir=1
   	endif
   	If Sprite X(Enemy+12)>=756 And Sprite Visible(Enemy+12)=1
   		GrnEnemyDir=0
   	endif
   next enemy
   Rem Change the directional flag if Purple enemies reach edge of screen
   For Enemy=1 to 10
   	If Sprite X(Enemy+22)<=0 And Sprite Visible(Enemy+22)=1
   		PurpEnemyDir=1
   	endif
   	If Sprite X(Enemy+22)>=756 And Sprite Visible(Enemy+22)=1
   		PurpEnemyDir=0
   	endif
   next enemy
   Rem When enemies reach edge of screen increase Y variable so enemies go down
   For Enemy=1 to 30
   	If Sprite X(Enemy+2)>=756 And Sprite Visible(Enemy+2)=1
   		EnemyY=EnemyY+2
   	endif
   	If Sprite X(Enemy+2)<=0 And Sprite Visible(Enemy+2)=1
			EnemyY=EnemyY+2
		Endif
   next enemy
   Rem our CLS equivalent
   fill memory mem_loc, 0, 1920000

   for s=0 to starquantity

      sx# = stars(s).x

      Rem works out where in memory to plot our dot!
      mem_y = int(stars(s).y)*(800*4)
      mem_x = (int(sx#)*4)
      mem_location = mem_x + mem_y

		Rem plots
      if mem_location > 1 and mem_location < 1920000
         write memblock dword 1, mem_location, stars(s).color
      endif

		Rem moves the star
      sx# = sx# - stars(s).speed
      if sx# < 0 then sx# = 800
      stars(s).x = sx#

   next s

	Rem This copies the pixel data from memory to the screen
   lock pixels
   copy memory get pixels pointer(), mem_loc, 1920000
   unlock pixels
   Rem refresh screen
   Sync
Loop

if you need to compile it i'll send you the media.
Thanx

Back to top

Profile PM Email Website

Lampton Worm

22

Years of Service

User Offline

Joined: 4th Sep 2002

Location: United Kingdom

Posted: 19th May 2004 21:58

Hi,

Dont worry about the media, I just replace your image load with an image grab of a box

So, anyway, it worked fine for me, I could see a ton of scrolling stars, not sure what the problem-o is at your side. I've attached a snap -

- does that look about right?

p.s. looks good so far, I could also shoot and zap the invaders.

Cheers.

Back to top

Profile PM Website

GameMaker Jason

21

Years of Service

User Offline

Joined: 22nd Nov 2003

Location: UK

Posted: 19th May 2004 23:07 Edited at: 19th May 2004 23:24

Do you think that i run out of ram? how much do you have?
My game has also slowed by nearly 3 times.

have's My Shot:

Back to top

Profile PM Email Website

Lampton Worm

22

Years of Service

User Offline

Joined: 4th Sep 2002

Location: United Kingdom

Posted: 20th May 2004 00:24

Hi,

Not all of the image downloaded for me so I can't see the bottom of the screen!

I have 256mb ram btw, I did see a weird memblock issue once where it only worked correctly in full screen exclusive, so you may want to try some different modes.

To be honest, you may want to just use paste image instead... paste image is fast.

Cheers.

Back to top

Profile PM Website

GameMaker Jason

21

Years of Service

User Offline

Joined: 22nd Nov 2003

Location: UK

Posted: 20th May 2004 20:50

I'm tring to make my aliens reappear once they are all destroyed but it doesn't work properally i've tried multiple thing's
heres my latest:

Rem Project: Space Invaders
Rem Created: 16/05/2004 11:04:38

Rem ***** Main Source File *****

Rem Set the screen size and sync rate
Set Display Mode 800,600,32
Sync On : Sync Rate 120 : Hide Mouse

Rem Define Variables
PlayerX = 400-10
PlayerY = 550
BulletX = PlayerX+20
BulletY = 550
EnemyY=100
starquantity = 600
starlayers = 5
speedfactor# = 0.50
SoundSpeed=35000
Score=0
EnemiesLeft=30

Rem Type for the move background
type starfield

X AS FLOAT
   Y AS FLOAT
   Z AS INTEGER
   speed AS FLOAT
   color AS DWORD

endtype

Rem Array of stars
dim stars(starquantity) as starfield

rem Create the location of the stars
for s=0 to starquantity

stars(s).x = rnd(800)
   stars(s).y = rnd(800)
   stars(s).z = int(s/(starquantity/starlayers))+1
   stars(s).speed = stars(s).z * speedfactor#
   temp_col = (255/starlayers) * stars(s).z
   stars(s).color = rgb(rnd(255),rnd(255),rnd(255))

next s

Rem our memblock - this is calculated from the following: screen X * screen Y * 4 (bytes per pixel)
make memblock 1,2560000
mem_loc AS DWORD
mem_loc = get memblock ptr(1)

Rem Load media in loop
For t=1 to 1
   rem Load image
   Load Image "images\ship1.png",1
   Load Image "images\bluenemy.png",2
   Load Image "images\grnenemy.png",3
   Load Image "images\purpenemy.png",4
   Load Image "images\bottomleft+right.png",5
   Load Image "images\bullete.png",6
   Load Image "images\bulletp.png",7
   Load Image "images\ship2.png",8
   rem load Theme Sound
   Load Sound "Music\Space Invaders Background.WAV",1
   rem Set the sound speed
   Set Sound Speed 1,35000
   rem Loop Theme Sound
   Loop Sound 1
next t

Set text Size 20

Rem Draw Blue Enemies
For Enemy=1 to 10
	Sprite Enemy+2,Enemy*67,100,2
Next Enemy

Rem Draw Green Enemies
For Enemy=1 to 10
	Sprite Enemy+12,Enemy*67,200,3
Next Enemy

Rem Draw Purple Enemies
For Enemy=1 to 10
	Sprite Enemy+22,Enemy*67,300,4
Next Enemy

Rem Create and hide bullet for use in game
Sprite 2,0,0,7
Hide Sprite 2

Rem main Loop (engine)
Do
	Rem Update the Blue Enemies position
	For Enemy=1 to 10
		BlueEnemyX=Sprite X(Enemy+2)
		If BlueEnemyDir=1
			Sprite Enemy+2,BlueEnemyX+2,EnemyY,2
		Endif
		If BlueEnemyDir=0
			Sprite Enemy+2,BlueEnemyX-2,EnemyY,2
		Endif
		If Sprite Visible(2)=1 And Sprite Visible(Enemy+2)=1 And Sprite Hit(2,Enemy+2)
			Hide Sprite Enemy+2
			BulletY=550
			Hide Sprite 2
			SoundSpeed=SoundSpeed+250
			Score=Score+3
			EnemiesLeft=EnemiesLeft-1
		endif
	Next Enemy
	Rem Update the Green Enemies position
	For Enemy=1 to 10
		GrnEnemyX=Sprite X(Enemy+12)
		If GrnEnemyDir=1
			Sprite Enemy+12,GrnEnemyX+2,EnemyY+100,3
		Endif
		If GrnEnemyDir=0
			Sprite Enemy+12,GrnEnemyX-2,EnemyY+100,3
		Endif
		If Sprite Visible(2)=1 And Sprite Visible(Enemy+12)=1 And Sprite Hit(2,Enemy+12)
			Hide Sprite Enemy+12
			BulletY=550
			Hide Sprite 2
			SoundSpeed=SoundSpeed+250
			Score=Score+2
			EnemiesLeft=EnemiesLeft-1
		endif
	Next Enemy
	Rem Update the Purple Enemies position
	For Enemy=1 to 10
		PurpEnemyX=Sprite X(Enemy+22)
		If PurpEnemyDir=1
			Sprite Enemy+22,PurpEnemyX+2,EnemyY+200,4
		Endif
		If PurpEnemyDir=0
			Sprite Enemy+22,PurpEnemyX-2,EnemyY+200,4
		Endif
		If Sprite Visible(2)=1 And Sprite Visible(Enemy+22)=1 And Sprite Hit(2,Enemy+22)
			Hide Sprite Enemy+22
			BulletY=550
			Hide Sprite 2
			SoundSpeed=SoundSpeed+250
			Score=Score+1
			EnemiesLeft=EnemiesLeft-1
		endif
	Next Enemy
   rem Exit the program
   If Escapekey()=1 Then End
   rem Create/Repoition Player Ship
   Sprite 1,PlayerX,PlayerY,1
   rem Move Player Ship
   If Leftkey()=1 And PlayerX>=0 Then PlayerX = PlayerX-4.5
   If Rightkey()=1 And PlayerX<=750 Then playerX = PlayerX+4.5
   rem Release bullet from ship
   If Spacekey()=1 Then Show Sprite 2 : Sprite 2,BulletX,BulletY,7 : Sprite 2,BulletX,BulletY,7
   If Sprite Visible(2)=1 Then BulletY=BulletY-5 : Sprite 2,BulletX,BulletY,7
   If BulletY<=04
   	Hide Sprite 2
   	BulletY=550
   Endif
   Rem Update Bullet X when bullet is hidden
   If Sprite Visible(2)=0
   	BulletX=PlayerX+20
   endif
   Rem Change the directional flag if Blue enemies reach edge of screen
   For Enemy=1 to 10
   	If Sprite X(Enemy+2)<=0 And Sprite Visible(Enemy+2)=1
   		BlueEnemyDir=1
   	endif
   	If Sprite X(Enemy+2)>=756 And Sprite Visible(Enemy+2)=1
   		BlueEnemyDir=0
   	endif
   next enemy
   Rem Change the directional flag if Green enemies reach edge of screen
   For Enemy=1 to 10
   	If Sprite X(Enemy+12)<=0 And Sprite Visible(Enemy+12)=1
   		GrnEnemyDir=1
   	endif
   	If Sprite X(Enemy+12)>=756 And Sprite Visible(Enemy+12)=1
   		GrnEnemyDir=0
   	endif
   next enemy
   Rem Change the directional flag if Purple enemies reach edge of screen
   For Enemy=1 to 10
   	If Sprite X(Enemy+22)<=0 And Sprite Visible(Enemy+22)=1
   		PurpEnemyDir=1
   	endif
   	If Sprite X(Enemy+22)>=756 And Sprite Visible(Enemy+22)=1
   		PurpEnemyDir=0
   	endif
   next enemy
   Rem When enemies reach edge of screen increase Y variable so enemies go down
   For Enemy=1 to 30
   	If Sprite X(Enemy+2)>=756 And Sprite Visible(Enemy+2)=1
   		EnemyY=EnemyY+2
   	endif
   	If Sprite X(Enemy+2)<=0 And Sprite Visible(Enemy+2)=1
			EnemyY=EnemyY+2
		Endif
   next enemy
   Rem our CLS equivalent
   fill memory mem_loc, 0, 2560000

for s=0 to starquantity

sx# = stars(s).x

Rem works out where in memory to plot our dot!
      mem_y = int(stars(s).y)*(800*4)
      mem_x = (int(sx#)*4)
      mem_location = mem_x + mem_y

Rem plots
      if mem_location > 1 and mem_location < 2560000
         write memblock dword 1, mem_location, stars(s).color
      endif

Rem moves the star
      sx# = sx# - stars(s).speed
      if sx# < 0 then sx# = 800
      stars(s).x = sx#

next s

Rem This copies the pixel data from memory to the screen
   lock pixels
   copy memory get pixels pointer(), mem_loc, 2560000
   unlock pixels
   Rem spedd up music
   
   For Enemy=1 to 30
   	If Sprite Visible(Enemy+2)=0 And EnemiesLeft=0
   		Show Sprite Enemy+2
   		EnemiesLeft=30
   	endif
   next Enemy
   Set Sound Speed 1,SoundSpeed
   text 10,10,"Score: "+Str$(Score)
   Rem refresh screen
   Sync
Loop

Rem Project: Space Invaders
Rem Created: 16/05/2004 11:04:38

Rem ***** Main Source File *****

Rem Set the screen size and sync rate
Set Display Mode 800,600,32
Sync On : Sync Rate 120 : Hide Mouse

Rem Define Variables
PlayerX = 400-10
PlayerY = 550
BulletX = PlayerX+20
BulletY = 550
EnemyY=100
starquantity = 600
starlayers = 5
speedfactor# = 0.50
SoundSpeed=35000
Score=0
EnemiesLeft=30

Rem Type for the move background
type starfield

   X AS FLOAT
   Y AS FLOAT
   Z AS INTEGER
   speed AS FLOAT
   color AS DWORD

endtype

Rem Array of stars
dim stars(starquantity) as starfield

rem Create the location of the stars
for s=0 to starquantity

   stars(s).x = rnd(800)
   stars(s).y = rnd(800)
   stars(s).z = int(s/(starquantity/starlayers))+1
   stars(s).speed = stars(s).z * speedfactor#
   temp_col = (255/starlayers) * stars(s).z
   stars(s).color = rgb(rnd(255),rnd(255),rnd(255))

next s

Rem our memblock - this is calculated from the following: screen X * screen Y * 4 (bytes per pixel)
make memblock 1,2560000
mem_loc AS DWORD
mem_loc = get memblock ptr(1)

Rem Load media in loop
For t=1 to 1
   rem Load image
   Load Image "images\ship1.png",1
   Load Image "images\bluenemy.png",2
   Load Image "images\grnenemy.png",3
   Load Image "images\purpenemy.png",4
   Load Image "images\bottomleft+right.png",5
   Load Image "images\bullete.png",6
   Load Image "images\bulletp.png",7
   Load Image "images\ship2.png",8
   rem load Theme Sound
   Load Sound "Music\Space Invaders Background.WAV",1
   rem Set the sound speed
   Set Sound Speed 1,35000
   rem Loop Theme Sound
   Loop Sound 1
next t

Set text Size 20

Rem Draw Blue Enemies
For Enemy=1 to 10
	Sprite Enemy+2,Enemy*67,100,2
Next Enemy

Rem Draw Green Enemies
For Enemy=1 to 10
	Sprite Enemy+12,Enemy*67,200,3
Next Enemy

Rem Draw Purple Enemies
For Enemy=1 to 10
	Sprite Enemy+22,Enemy*67,300,4
Next Enemy

Rem Create and hide bullet for use in game
Sprite 2,0,0,7
Hide Sprite 2

Rem main Loop (engine)
Do
	Rem Update the Blue Enemies position
	For Enemy=1 to 10
		BlueEnemyX=Sprite X(Enemy+2)
		If BlueEnemyDir=1
			Sprite Enemy+2,BlueEnemyX+2,EnemyY,2
		Endif
		If BlueEnemyDir=0
			Sprite Enemy+2,BlueEnemyX-2,EnemyY,2
		Endif
		If Sprite Visible(2)=1 And Sprite Visible(Enemy+2)=1 And Sprite Hit(2,Enemy+2)
			Hide Sprite Enemy+2
			BulletY=550
			Hide Sprite 2
			SoundSpeed=SoundSpeed+250
			Score=Score+3
			EnemiesLeft=EnemiesLeft-1
		endif
	Next Enemy
	Rem Update the Green Enemies position
	For Enemy=1 to 10
		GrnEnemyX=Sprite X(Enemy+12)
		If GrnEnemyDir=1
			Sprite Enemy+12,GrnEnemyX+2,EnemyY+100,3
		Endif
		If GrnEnemyDir=0
			Sprite Enemy+12,GrnEnemyX-2,EnemyY+100,3
		Endif
		If Sprite Visible(2)=1 And Sprite Visible(Enemy+12)=1 And Sprite Hit(2,Enemy+12)
			Hide Sprite Enemy+12
			BulletY=550
			Hide Sprite 2
			SoundSpeed=SoundSpeed+250
			Score=Score+2
			EnemiesLeft=EnemiesLeft-1
		endif
	Next Enemy
	Rem Update the Purple Enemies position
	For Enemy=1 to 10
		PurpEnemyX=Sprite X(Enemy+22)
		If PurpEnemyDir=1
			Sprite Enemy+22,PurpEnemyX+2,EnemyY+200,4
		Endif
		If PurpEnemyDir=0
			Sprite Enemy+22,PurpEnemyX-2,EnemyY+200,4
		Endif
		If Sprite Visible(2)=1 And Sprite Visible(Enemy+22)=1 And Sprite Hit(2,Enemy+22)
			Hide Sprite Enemy+22
			BulletY=550
			Hide Sprite 2
			SoundSpeed=SoundSpeed+250
			Score=Score+1
			EnemiesLeft=EnemiesLeft-1
		endif
	Next Enemy
   rem Exit the program
   If Escapekey()=1 Then End
   rem Create/Repoition Player Ship
   Sprite 1,PlayerX,PlayerY,1
   rem Move Player Ship
   If Leftkey()=1 And PlayerX>=0 Then PlayerX = PlayerX-4.5
   If Rightkey()=1 And PlayerX<=750 Then playerX = PlayerX+4.5
   rem Release bullet from ship
   If Spacekey()=1 Then Show Sprite 2 : Sprite 2,BulletX,BulletY,7 : Sprite 2,BulletX,BulletY,7
   If Sprite Visible(2)=1 Then BulletY=BulletY-5 : Sprite 2,BulletX,BulletY,7
   If BulletY<=04
   	Hide Sprite 2
   	BulletY=550
   Endif
   Rem Update Bullet X when bullet is hidden
   If Sprite Visible(2)=0
   	BulletX=PlayerX+20
   endif
   Rem Change the directional flag if Blue enemies reach edge of screen
   For Enemy=1 to 10
   	If Sprite X(Enemy+2)<=0 And Sprite Visible(Enemy+2)=1
   		BlueEnemyDir=1
   	endif
   	If Sprite X(Enemy+2)>=756 And Sprite Visible(Enemy+2)=1
   		BlueEnemyDir=0
   	endif
   next enemy
   Rem Change the directional flag if Green enemies reach edge of screen
   For Enemy=1 to 10
   	If Sprite X(Enemy+12)<=0 And Sprite Visible(Enemy+12)=1
   		GrnEnemyDir=1
   	endif
   	If Sprite X(Enemy+12)>=756 And Sprite Visible(Enemy+12)=1
   		GrnEnemyDir=0
   	endif
   next enemy
   Rem Change the directional flag if Purple enemies reach edge of screen
   For Enemy=1 to 10
   	If Sprite X(Enemy+22)<=0 And Sprite Visible(Enemy+22)=1
   		PurpEnemyDir=1
   	endif
   	If Sprite X(Enemy+22)>=756 And Sprite Visible(Enemy+22)=1
   		PurpEnemyDir=0
   	endif
   next enemy
   Rem When enemies reach edge of screen increase Y variable so enemies go down
   For Enemy=1 to 30
   	If Sprite X(Enemy+2)>=756 And Sprite Visible(Enemy+2)=1
   		EnemyY=EnemyY+2
   	endif
   	If Sprite X(Enemy+2)<=0 And Sprite Visible(Enemy+2)=1
			EnemyY=EnemyY+2
		Endif
   next enemy
   Rem our CLS equivalent
   fill memory mem_loc, 0, 2560000

   for s=0 to starquantity

      sx# = stars(s).x

      Rem works out where in memory to plot our dot!
      mem_y = int(stars(s).y)*(800*4)
      mem_x = (int(sx#)*4)
      mem_location = mem_x + mem_y

		Rem plots
      if mem_location > 1 and mem_location < 2560000
         write memblock dword 1, mem_location, stars(s).color
      endif

		Rem moves the star
      sx# = sx# - stars(s).speed
      if sx# < 0 then sx# = 800
      stars(s).x = sx#

   next s

	Rem This copies the pixel data from memory to the screen
   lock pixels
   copy memory get pixels pointer(), mem_loc, 2560000
   unlock pixels
   Rem spedd up music
   
   For Enemy=1 to 30
   	If Sprite Visible(Enemy+2)=0 And EnemiesLeft=0
   		Show Sprite Enemy+2
   		EnemiesLeft=30
   	endif
   next Enemy
   Set Sound Speed 1,SoundSpeed
   text 10,10,"Score: "+Str$(Score)
   Rem refresh screen
   Sync
Loop

thanx

Back to top

Profile PM Email Website

Lampton Worm

22

Years of Service

User Offline

Joined: 4th Sep 2002

Location: United Kingdom

Posted: 21st May 2004 12:42

Hi,

I'm not at my DBP machine today, but I'll try to check this out later tonight for ya.

Cheers.

Back to top

Profile PM Website

Lampton Worm

22

Years of Service

User Offline

Joined: 4th Sep 2002

Location: United Kingdom

Posted: 22nd May 2004 16:14

Hi,

Sorry for the delay, I ended up leave working late last night. Ok, so I think its a logic problem where you try to make all the sprites visible again, but you had "and enemiesleft=0" in the for loop, so it was getting in a tangle.

To debug it, I added some quick code to the top to fake destroying 29 enemies in a single key press, save you killing 'em all each time (as fun at this is!), and from there I monitored the value of enemiesleft, and saw that when you had killed them all, it was set to 29, this releaved the logic error.

So, what I've done is make a spawnenemy subroutine, and when enemiesleft reaches zero, we respawn (coz this does positions 'em back where they below), re-show the sprites, and set enemiesleft back to 30. I also use that subrouting for the initial creation of the enemies.

I've commented the code (quickly!), left in my "down to 1 enemy" debug, and coz I don't have your media I quickly used boxes again instead. p.s. I commented out the sound also as I don't have the wavs.

Here ya go...

Rem Project: Space Invaders
Rem Created: 16/05/2004 11:04:38

Rem ***** Main Source File *****

Rem Set the screen size and sync rate
Set Display Mode 800,600,32
Sync On : Sync Rate 120 : Hide Mouse

Rem Define Variables
PlayerX = 400-10
PlayerY = 550
BulletX = PlayerX+20
BulletY = 550
EnemyY=100
starquantity = 600
starlayers = 5
speedfactor# = 0.50
SoundSpeed=35000
Score=0
EnemiesLeft=30

Rem Type for the move background
type starfield

X AS FLOAT
   Y AS FLOAT
   Z AS INTEGER
   speed AS FLOAT
   color AS DWORD

endtype

Rem Array of stars
dim stars(starquantity) as starfield

rem Create the location of the stars
for s=0 to starquantity

stars(s).x = rnd(800)
   stars(s).y = rnd(800)
   stars(s).z = int(s/(starquantity/starlayers))+1
   stars(s).speed = stars(s).z * speedfactor#
   temp_col = (255/starlayers) * stars(s).z
   stars(s).color = rgb(rnd(255),rnd(255),rnd(255))

next s

Rem our memblock - this is calculated from the following: screen X * screen Y * 4 (bytes per pixel)
make memblock 1,2560000
mem_loc AS DWORD
mem_loc = get memblock ptr(1)

box 0,0,24,24
Rem Load media in loop
For t=1 to 1
   rem Load image
   for i=1 to 8
      get image i,0,0,24,24
   next i
`   Load Image "images\ship1.png",1
`   Load Image "images\bluenemy.png",2
`   Load Image "images\grnenemy.png",3
`   Load Image "images\purpenemy.png",4
`   Load Image "images\bottomleft+right.png",5
`   Load Image "images\bullete.png",6
`   Load Image "images\bulletp.png",7
`   Load Image "images\ship2.png",8
   rem load Theme Sound
`   Load Sound "Music\Space Invaders Background.WAV",1
   rem Set the sound speed
`   Set Sound Speed 1,35000
   rem Loop Theme Sound
`   Loop Sound 1
next t

Set text Size 20

gosub spawn_enemies

Rem Create and hide bullet for use in game
Sprite 2,0,0,7
Hide Sprite 2

Rem main Loop (engine)
Do

`LW, some debug to quickly leave us with 1 enemy to toy with ;-)
if returnkey()=1
   wait 100
   for Enemy=2 to 30
      Hide Sprite Enemy+2
      BulletY=550
      Hide Sprite 2
      EnemiesLeft=EnemiesLeft-1
   next i
endif

Rem Update the Blue Enemies position
   For Enemy=1 to 10
      BlueEnemyX=Sprite X(Enemy+2)
      If BlueEnemyDir=1
         Sprite Enemy+2,BlueEnemyX+2,EnemyY,2
      Endif
      If BlueEnemyDir=0
         Sprite Enemy+2,BlueEnemyX-2,EnemyY,2
      Endif
      If Sprite Visible(2)=1 And Sprite Visible(Enemy+2)=1 And Sprite Hit(2,Enemy+2)
         Hide Sprite Enemy+2
         BulletY=550
         Hide Sprite 2
         SoundSpeed=SoundSpeed+250
         Score=Score+3
         EnemiesLeft=EnemiesLeft-1
      endif
   Next Enemy
   Rem Update the Green Enemies position
   For Enemy=1 to 10
      GrnEnemyX=Sprite X(Enemy+12)
      If GrnEnemyDir=1
         Sprite Enemy+12,GrnEnemyX+2,EnemyY+100,3
      Endif
      If GrnEnemyDir=0
         Sprite Enemy+12,GrnEnemyX-2,EnemyY+100,3
      Endif
      If Sprite Visible(2)=1 And Sprite Visible(Enemy+12)=1 And Sprite Hit(2,Enemy+12)
         Hide Sprite Enemy+12
         BulletY=550
         Hide Sprite 2
         SoundSpeed=SoundSpeed+250
         Score=Score+2
         EnemiesLeft=EnemiesLeft-1
      endif
   Next Enemy
   Rem Update the Purple Enemies position
   For Enemy=1 to 10
      PurpEnemyX=Sprite X(Enemy+22)
      If PurpEnemyDir=1
         Sprite Enemy+22,PurpEnemyX+2,EnemyY+200,4
      Endif
      If PurpEnemyDir=0
         Sprite Enemy+22,PurpEnemyX-2,EnemyY+200,4
      Endif
      If Sprite Visible(2)=1 And Sprite Visible(Enemy+22)=1 And Sprite Hit(2,Enemy+22)
         Hide Sprite Enemy+22
         BulletY=550
         Hide Sprite 2
         SoundSpeed=SoundSpeed+250
         Score=Score+1
         EnemiesLeft=EnemiesLeft-1
      endif
   Next Enemy
   rem Exit the program
   If Escapekey()=1 Then End
   rem Create/Repoition Player Ship
   Sprite 1,PlayerX,PlayerY,1
   rem Move Player Ship
   If Leftkey()=1 And PlayerX>=0 Then PlayerX = PlayerX-4.5
   If Rightkey()=1 And PlayerX<=750 Then playerX = PlayerX+4.5
   rem Release bullet from ship
   If Spacekey()=1 Then Show Sprite 2 : Sprite 2,BulletX,BulletY,7 : Sprite 2,BulletX,BulletY,7
   If Sprite Visible(2)=1 Then BulletY=BulletY-5 : Sprite 2,BulletX,BulletY,7
   If BulletY<=04
      Hide Sprite 2
      BulletY=550
   Endif
   Rem Update Bullet X when bullet is hidden
   If Sprite Visible(2)=0
      BulletX=PlayerX+20
   endif
   Rem Change the directional flag if Blue enemies reach edge of screen
   For Enemy=1 to 10
      If Sprite X(Enemy+2)<=0 And Sprite Visible(Enemy+2)=1
         BlueEnemyDir=1
      endif
      If Sprite X(Enemy+2)>=756 And Sprite Visible(Enemy+2)=1
         BlueEnemyDir=0
      endif
   next enemy
   Rem Change the directional flag if Green enemies reach edge of screen
   For Enemy=1 to 10
      If Sprite X(Enemy+12)<=0 And Sprite Visible(Enemy+12)=1
         GrnEnemyDir=1
      endif
      If Sprite X(Enemy+12)>=756 And Sprite Visible(Enemy+12)=1
         GrnEnemyDir=0
      endif
   next enemy
   Rem Change the directional flag if Purple enemies reach edge of screen
   For Enemy=1 to 10
      If Sprite X(Enemy+22)<=0 And Sprite Visible(Enemy+22)=1
         PurpEnemyDir=1
      endif
      If Sprite X(Enemy+22)>=756 And Sprite Visible(Enemy+22)=1
         PurpEnemyDir=0
      endif
   next enemy
   Rem When enemies reach edge of screen increase Y variable so enemies go down
   For Enemy=1 to 30
      If Sprite X(Enemy+2)>=756 And Sprite Visible(Enemy+2)=1
         EnemyY=EnemyY+2
      endif
      If Sprite X(Enemy+2)<=0 And Sprite Visible(Enemy+2)=1
         EnemyY=EnemyY+2
      Endif
   next enemy
   Rem our CLS equivalent
   fill memory mem_loc, 0, 2560000

for s=0 to starquantity

sx# = stars(s).x

Rem works out where in memory to plot our dot!
      mem_y = int(stars(s).y)*(800*4)
      mem_x = (int(sx#)*4)
      mem_location = mem_x + mem_y

Rem plots
      if mem_location > 1 and mem_location < 2560000
         write memblock dword 1, mem_location, stars(s).color
      endif

Rem moves the star
      sx# = sx# - stars(s).speed
      if sx# < 0 then sx# = 800
      stars(s).x = sx#

next s

Rem This copies the pixel data from memory to the screen
   lock pixels
   copy memory get pixels pointer(), mem_loc, 2560000
   unlock pixels
   Rem spedd up music

`LW: if you've zapped all enemies...
   if EnemiesLeft=0                       `: If we've zapped all the enemies...
      gosub spawn_enemies                 `: put them back in their start positions
      For Enemy=1 to 30                   `: loop through and make them visible
         If Sprite Visible(Enemy+2)=0
            Show Sprite Enemy+2
         endif
      next Enemy
      EnemiesLeft=30                      `: re-set enemiessleft counter
   endif
`   Set Sound Speed 1,SoundSpeed
   text 10,10,"Score: "+Str$(Score)
   text 10,30,str$(EnemiesLeft)
   Rem refresh screen
   Sync
Loop

spawn_enemies:
Rem Draw Blue Enemies
For Enemy=1 to 10
   Sprite Enemy+2,Enemy*67,100,2
Next Enemy

Rem Draw Green Enemies
For Enemy=1 to 10
   Sprite Enemy+12,Enemy*67,200,3
Next Enemy

Rem Draw Purple Enemies
For Enemy=1 to 10
   Sprite Enemy+22,Enemy*67,300,4
Next Enemy
return

Rem Project: Space Invaders
Rem Created: 16/05/2004 11:04:38

Rem ***** Main Source File *****

Rem Set the screen size and sync rate
Set Display Mode 800,600,32
Sync On : Sync Rate 120 : Hide Mouse

Rem Define Variables
PlayerX = 400-10
PlayerY = 550
BulletX = PlayerX+20
BulletY = 550
EnemyY=100
starquantity = 600
starlayers = 5
speedfactor# = 0.50
SoundSpeed=35000
Score=0
EnemiesLeft=30

Rem Type for the move background
type starfield

   X AS FLOAT
   Y AS FLOAT
   Z AS INTEGER
   speed AS FLOAT
   color AS DWORD

endtype

Rem Array of stars
dim stars(starquantity) as starfield

rem Create the location of the stars
for s=0 to starquantity

   stars(s).x = rnd(800)
   stars(s).y = rnd(800)
   stars(s).z = int(s/(starquantity/starlayers))+1
   stars(s).speed = stars(s).z * speedfactor#
   temp_col = (255/starlayers) * stars(s).z
   stars(s).color = rgb(rnd(255),rnd(255),rnd(255))

next s

Rem our memblock - this is calculated from the following: screen X * screen Y * 4 (bytes per pixel)
make memblock 1,2560000
mem_loc AS DWORD
mem_loc = get memblock ptr(1)

box 0,0,24,24
Rem Load media in loop
For t=1 to 1
   rem Load image
   for i=1 to 8
      get image i,0,0,24,24
   next i
`   Load Image "images\ship1.png",1
`   Load Image "images\bluenemy.png",2
`   Load Image "images\grnenemy.png",3
`   Load Image "images\purpenemy.png",4
`   Load Image "images\bottomleft+right.png",5
`   Load Image "images\bullete.png",6
`   Load Image "images\bulletp.png",7
`   Load Image "images\ship2.png",8
   rem load Theme Sound
`   Load Sound "Music\Space Invaders Background.WAV",1
   rem Set the sound speed
`   Set Sound Speed 1,35000
   rem Loop Theme Sound
`   Loop Sound 1
next t

Set text Size 20

gosub spawn_enemies

Rem Create and hide bullet for use in game
Sprite 2,0,0,7
Hide Sprite 2

Rem main Loop (engine)
Do

`LW, some debug to quickly leave us with 1 enemy to toy with ;-)
if returnkey()=1
   wait 100
   for Enemy=2 to 30
      Hide Sprite Enemy+2
      BulletY=550
      Hide Sprite 2
      EnemiesLeft=EnemiesLeft-1
   next i
endif

   Rem Update the Blue Enemies position
   For Enemy=1 to 10
      BlueEnemyX=Sprite X(Enemy+2)
      If BlueEnemyDir=1
         Sprite Enemy+2,BlueEnemyX+2,EnemyY,2
      Endif
      If BlueEnemyDir=0
         Sprite Enemy+2,BlueEnemyX-2,EnemyY,2
      Endif
      If Sprite Visible(2)=1 And Sprite Visible(Enemy+2)=1 And Sprite Hit(2,Enemy+2)
         Hide Sprite Enemy+2
         BulletY=550
         Hide Sprite 2
         SoundSpeed=SoundSpeed+250
         Score=Score+3
         EnemiesLeft=EnemiesLeft-1
      endif
   Next Enemy
   Rem Update the Green Enemies position
   For Enemy=1 to 10
      GrnEnemyX=Sprite X(Enemy+12)
      If GrnEnemyDir=1
         Sprite Enemy+12,GrnEnemyX+2,EnemyY+100,3
      Endif
      If GrnEnemyDir=0
         Sprite Enemy+12,GrnEnemyX-2,EnemyY+100,3
      Endif
      If Sprite Visible(2)=1 And Sprite Visible(Enemy+12)=1 And Sprite Hit(2,Enemy+12)
         Hide Sprite Enemy+12
         BulletY=550
         Hide Sprite 2
         SoundSpeed=SoundSpeed+250
         Score=Score+2
         EnemiesLeft=EnemiesLeft-1
      endif
   Next Enemy
   Rem Update the Purple Enemies position
   For Enemy=1 to 10
      PurpEnemyX=Sprite X(Enemy+22)
      If PurpEnemyDir=1
         Sprite Enemy+22,PurpEnemyX+2,EnemyY+200,4
      Endif
      If PurpEnemyDir=0
         Sprite Enemy+22,PurpEnemyX-2,EnemyY+200,4
      Endif
      If Sprite Visible(2)=1 And Sprite Visible(Enemy+22)=1 And Sprite Hit(2,Enemy+22)
         Hide Sprite Enemy+22
         BulletY=550
         Hide Sprite 2
         SoundSpeed=SoundSpeed+250
         Score=Score+1
         EnemiesLeft=EnemiesLeft-1
      endif
   Next Enemy
   rem Exit the program
   If Escapekey()=1 Then End
   rem Create/Repoition Player Ship
   Sprite 1,PlayerX,PlayerY,1
   rem Move Player Ship
   If Leftkey()=1 And PlayerX>=0 Then PlayerX = PlayerX-4.5
   If Rightkey()=1 And PlayerX<=750 Then playerX = PlayerX+4.5
   rem Release bullet from ship
   If Spacekey()=1 Then Show Sprite 2 : Sprite 2,BulletX,BulletY,7 : Sprite 2,BulletX,BulletY,7
   If Sprite Visible(2)=1 Then BulletY=BulletY-5 : Sprite 2,BulletX,BulletY,7
   If BulletY<=04
      Hide Sprite 2
      BulletY=550
   Endif
   Rem Update Bullet X when bullet is hidden
   If Sprite Visible(2)=0
      BulletX=PlayerX+20
   endif
   Rem Change the directional flag if Blue enemies reach edge of screen
   For Enemy=1 to 10
      If Sprite X(Enemy+2)<=0 And Sprite Visible(Enemy+2)=1
         BlueEnemyDir=1
      endif
      If Sprite X(Enemy+2)>=756 And Sprite Visible(Enemy+2)=1
         BlueEnemyDir=0
      endif
   next enemy
   Rem Change the directional flag if Green enemies reach edge of screen
   For Enemy=1 to 10
      If Sprite X(Enemy+12)<=0 And Sprite Visible(Enemy+12)=1
         GrnEnemyDir=1
      endif
      If Sprite X(Enemy+12)>=756 And Sprite Visible(Enemy+12)=1
         GrnEnemyDir=0
      endif
   next enemy
   Rem Change the directional flag if Purple enemies reach edge of screen
   For Enemy=1 to 10
      If Sprite X(Enemy+22)<=0 And Sprite Visible(Enemy+22)=1
         PurpEnemyDir=1
      endif
      If Sprite X(Enemy+22)>=756 And Sprite Visible(Enemy+22)=1
         PurpEnemyDir=0
      endif
   next enemy
   Rem When enemies reach edge of screen increase Y variable so enemies go down
   For Enemy=1 to 30
      If Sprite X(Enemy+2)>=756 And Sprite Visible(Enemy+2)=1
         EnemyY=EnemyY+2
      endif
      If Sprite X(Enemy+2)<=0 And Sprite Visible(Enemy+2)=1
         EnemyY=EnemyY+2
      Endif
   next enemy
   Rem our CLS equivalent
   fill memory mem_loc, 0, 2560000

   for s=0 to starquantity

      sx# = stars(s).x

      Rem works out where in memory to plot our dot!
      mem_y = int(stars(s).y)*(800*4)
      mem_x = (int(sx#)*4)
      mem_location = mem_x + mem_y

      Rem plots
      if mem_location > 1 and mem_location < 2560000
         write memblock dword 1, mem_location, stars(s).color
      endif

      Rem moves the star
      sx# = sx# - stars(s).speed
      if sx# < 0 then sx# = 800
      stars(s).x = sx#

   next s

   Rem This copies the pixel data from memory to the screen
   lock pixels
   copy memory get pixels pointer(), mem_loc, 2560000
   unlock pixels
   Rem spedd up music

   `LW: if you've zapped all enemies...
   if EnemiesLeft=0                       `: If we've zapped all the enemies...
      gosub spawn_enemies                 `: put them back in their start positions
      For Enemy=1 to 30                   `: loop through and make them visible
         If Sprite Visible(Enemy+2)=0
            Show Sprite Enemy+2
         endif
      next Enemy
      EnemiesLeft=30                      `: re-set enemiessleft counter
   endif
`   Set Sound Speed 1,SoundSpeed
   text 10,10,"Score: "+Str$(Score)
   text 10,30,str$(EnemiesLeft)
   Rem refresh screen
   Sync
Loop

spawn_enemies:
Rem Draw Blue Enemies
For Enemy=1 to 10
   Sprite Enemy+2,Enemy*67,100,2
Next Enemy

Rem Draw Green Enemies
For Enemy=1 to 10
   Sprite Enemy+12,Enemy*67,200,3
Next Enemy

Rem Draw Purple Enemies
For Enemy=1 to 10
   Sprite Enemy+22,Enemy*67,300,4
Next Enemy
return

Hope it helps...
Cheers,

Back to top

Profile PM Website

GameMaker Jason

21

Years of Service

User Offline

Joined: 22nd Nov 2003

Location: UK

Posted: 23rd May 2004 01:44

I am not shure how to make my aliens shoot a bullet down to wards you when there is no aliens below them. how could i do this.

Rem Project: Space Invaders
Rem Created: 16/05/2004 11:04:38

Rem ***** Main Source File *****

Rem Set the screen size and sync rate
Set Display Mode 800,600,32
Sync On : Sync Rate 120 : Hide Mouse

Rem Define Variables
PlayerX = 400-10
PlayerY = 550
BulletX = PlayerX+20
BulletY = 550
EnemyY=100
starquantity = 600
starlayers = 5
speedfactor# = 0.50
SoundSpeed=35000
Score=0
Alpha1=255
Alpha2=255
Alpha3=255
Dim EnemyAttack(10,3)
Dim EnemyPositionX(10,3)
Dim EnemyPositionY(3)
EnemiesLeft=0
XMove=2
YMove#=2

Rem Type for the move background
type starfield

X AS FLOAT
   Y AS FLOAT
   Z AS INTEGER
   speed AS FLOAT
   color AS DWORD

endtype

Rem Array of stars
dim stars(starquantity) as starfield

rem Create the location of the stars
for s=0 to starquantity

stars(s).x = rnd(800)
   stars(s).y = rnd(800)
   stars(s).z = int(s/(starquantity/starlayers))+1
   stars(s).speed = stars(s).z * speedfactor#
   temp_col = (255/starlayers) * stars(s).z
   stars(s).color = rgb(rnd(255),rnd(255),rnd(255))

next s

Rem our memblock - this is calculated from the following: screen X * screen Y * 4 (bytes per pixel)
make memblock 1,2560000
mem_loc AS DWORD
mem_loc = get memblock ptr(1)

Rem Load media in loop
For t=1 to 1
   rem Load image
   Load Image "images\ship1.png",1
   Load Image "images\bluenemy.png",2
   Load Image "images\grnenemy.png",3
   Load Image "images\purpenemy.png",4
   Load Image "images\Shield.png",5
   Load Image "images\bullete.png",6
   Load Image "images\bulletp.png",7
   Load Image "images\ship2.png",8
   rem load Theme Sound
   Load Sound "Music\Space Invaders Background.WAV",1
   rem Set the sound speed
   Set Sound Speed 1,35000
   rem Loop Theme Sound
   Loop Sound 1
next t

Set text Size 20

Sprite 33,133,450,5
Sprite 34,383,450,5
Sprite 35,633,450,5

respawn:
Rem Draw Blue Enemies
For Enemy=1 to 10
	Sprite Enemy+2,Enemy*67,100,2
Next Enemy

Rem Draw Green Enemies
For Enemy=1 to 10
	Sprite Enemy+12,Enemy*67,200,3
Next Enemy

Rem Draw Purple Enemies
For Enemy=1 to 10
	Sprite Enemy+22,Enemy*67,300,4
Next Enemy

Rem Create and hide bullet for use in game
Sprite 2,0,0,7
Hide Sprite 2

For Enemy=1 to 10
	For Enemy2=3 to 3
		EnemyAttack(Enemy,Enemy2)=1
	Next Enemy2
next enemy

Rem main Loop (engine)
Do
	Rem Update the Blue Enemies position
	For Enemy=1 to 10
		EnemyPositionX(Enemy,1)=Sprite X(Enemy+2)
		If EnemyDir=1
			Sprite Enemy+2,EnemyPositionX(Enemy,1)+XMove,EnemyPositionY(1),2
		Endif
		If EnemyDir=0
			Sprite Enemy+2,EnemyPositionX(Enemy,1)-XMove,EnemyPositionY(1),2
		Endif
		If Sprite Visible(2)=1 And Sprite Visible(Enemy+2)=1 And Sprite Hit(2,Enemy+2)
			Hide Sprite Enemy+2
			BulletY=550
			Hide Sprite 2
			SoundSpeed=SoundSpeed+250
			Score=Score+3
			EnemiesLeft=EnemiesLeft+1
		endif
	Next Enemy
	Rem Update the Green Enemies position
	For Enemy=1 to 10
		EnemyPositionX(Enemy,2)=Sprite X(Enemy+12)
		If EnemyDir=1
			Sprite Enemy+12,EnemyPositionX(Enemy,2)+XMove,EnemyPositionY(2),3
		Endif
		If EnemyDir=0
			Sprite Enemy+12,EnemyPositionX(Enemy,2)-XMove,EnemyPositionY(2),3
		Endif
		If Sprite Visible(2)=1 And Sprite Visible(Enemy+12)=1 And Sprite Hit(2,Enemy+12)
			Hide Sprite Enemy+12
			BulletY=550
			Hide Sprite 2
			SoundSpeed=SoundSpeed+250
			Score=Score+2
			EnemiesLeft=EnemiesLeft+1
		endif
	Next Enemy
	Rem Update the Purple Enemies position
	For Enemy=1 to 10
		EnemyPositionX(Enemy,3)=Sprite X(Enemy+22)
		If EnemyDir=1
			Sprite Enemy+22,EnemyPositionX(Enemy,3)+XMove,EnemyPositionY(3),4
		Endif
		If EnemyDir=0
			Sprite Enemy+22,EnemyPositionX(Enemy,3)-XMove,EnemyPositionY(3),4
		Endif
		If Sprite Visible(2)=1 And Sprite Visible(Enemy+22)=1 And Sprite Hit(2,Enemy+22)
			Hide Sprite Enemy+22
			BulletY=550
			Hide Sprite 2
			SoundSpeed=SoundSpeed+250
			Score=Score+1
			EnemiesLeft=EnemiesLeft+1
		endif
	Next Enemy
   rem Exit the program
   If Escapekey()=1 Then End
   rem Create/Repoition Player Ship
   Sprite 1,PlayerX,PlayerY,1
   rem Move Player Ship
   If Leftkey()=1 And PlayerX>=0 Then PlayerX = PlayerX-4.5
   If Rightkey()=1 And PlayerX<=750 Then playerX = PlayerX+4.5
   rem Release bullet from ship
   If Spacekey()=1 Then Show Sprite 2 : Sprite 2,BulletX,BulletY,7 : Sprite 2,BulletX,BulletY,7
   If Sprite Visible(2)=1 Then BulletY=BulletY-8 : Sprite 2,BulletX,BulletY,7
   If BulletY<=0
   	Hide Sprite 2
   	BulletY=550
   Endif
   Rem Update Bullet X when bullet is hidden
   If Sprite Visible(2)=0
   	BulletX=PlayerX+20
   endif
   Rem Change the directional flag if Blue enemies reach edge of screen
   For Enemy=1 to 30
   	If Sprite X(Enemy+2)<=0 And Sprite Visible(Enemy+2)=1
   		EnemyDir=1
   	endif
   	If Sprite X(Enemy+2)>=756 And Sprite Visible(Enemy+2)=1
   		EnemyDir=0
   	Endif
   Next Enemy
   Rem When enemies reach edge of screen increase Y variable so enemies go down
   For Enemy=1 to 30
   	If Sprite X(Enemy+2)>=756 And Sprite Visible(Enemy+2)=1
   		EnemyY=EnemyY+YMove
   	endif
   	If Sprite X(Enemy+2)<=0 And Sprite Visible(Enemy+2)=1
			EnemyY=EnemyY+YMove
		Endif
   Next enemy
   For Enemy=1 to 30
   	If Sprite Y(Enemy+2)>450
   		End
   	Endif
   Next enemy
   If EnemiesLeft=30
      Gosub respawn
      For Enemy=1 to 30
         If Sprite Visible(Enemy+2)=0
            Show Sprite Enemy+2
         Endif
      next Enemy
      EnemiesLeft=0
   endif
   Rem our CLS equivalent
   fill memory mem_loc, 0, 2560000

for s=0 to starquantity

sx# = stars(s).x

Rem works out where in memory to plot our dot!
      mem_y = int(stars(s).y)*(800*4)
      mem_x = (int(sx#)*4)
      mem_location = mem_x + mem_y

Rem plots
      if mem_location > 1 and mem_location < 2560000
         write memblock dword 1, mem_location, stars(s).color
      endif

Rem moves the star
      sx# = sx# - stars(s).speed
      if sx# < 0 then sx# = 800
      stars(s).x = sx#

next s

Rem This copies the pixel data from memory to the screen
   lock pixels
   copy memory get pixels pointer(), mem_loc, 2560000
   unlock pixels
   Rem speed up music
   Set Sound Speed 1,SoundSpeed
   text 10,10,"Score: "+Str$(Score)
   Rem refresh screen
   Sync
Loop

respawn:
Rem Draw Blue Enemies
For Enemy=1 to 10
	Sprite Enemy+2,Enemy*67,100,2
Next Enemy

Rem Draw Green Enemies
For Enemy=1 to 10
	Sprite Enemy+12,Enemy*67,200,3
Next Enemy

Rem Draw Purple Enemies
For Enemy=1 to 10
	Sprite Enemy+22,Enemy*67,300,4
Next Enemy

EnemyPositionY(1)=100
EnemyPositionY(2)=200
EnemyPositionY(3)=300
XMove=XMove+1
YMove=YMove+0.5
Return

Rem Project: Space Invaders
Rem Created: 16/05/2004 11:04:38

Rem ***** Main Source File *****

Rem Set the screen size and sync rate
Set Display Mode 800,600,32
Sync On : Sync Rate 120 : Hide Mouse

Rem Define Variables
PlayerX = 400-10
PlayerY = 550
BulletX = PlayerX+20
BulletY = 550
EnemyY=100
starquantity = 600
starlayers = 5
speedfactor# = 0.50
SoundSpeed=35000
Score=0
Alpha1=255
Alpha2=255
Alpha3=255
Dim EnemyAttack(10,3)
Dim EnemyPositionX(10,3)
Dim EnemyPositionY(3)
EnemiesLeft=0
XMove=2
YMove#=2

Rem Type for the move background
type starfield

   X AS FLOAT
   Y AS FLOAT
   Z AS INTEGER
   speed AS FLOAT
   color AS DWORD

endtype

Rem Array of stars
dim stars(starquantity) as starfield

rem Create the location of the stars
for s=0 to starquantity

   stars(s).x = rnd(800)
   stars(s).y = rnd(800)
   stars(s).z = int(s/(starquantity/starlayers))+1
   stars(s).speed = stars(s).z * speedfactor#
   temp_col = (255/starlayers) * stars(s).z
   stars(s).color = rgb(rnd(255),rnd(255),rnd(255))

next s

Rem our memblock - this is calculated from the following: screen X * screen Y * 4 (bytes per pixel)
make memblock 1,2560000
mem_loc AS DWORD
mem_loc = get memblock ptr(1)

Rem Load media in loop
For t=1 to 1
   rem Load image
   Load Image "images\ship1.png",1
   Load Image "images\bluenemy.png",2
   Load Image "images\grnenemy.png",3
   Load Image "images\purpenemy.png",4
   Load Image "images\Shield.png",5
   Load Image "images\bullete.png",6
   Load Image "images\bulletp.png",7
   Load Image "images\ship2.png",8
   rem load Theme Sound
   Load Sound "Music\Space Invaders Background.WAV",1
   rem Set the sound speed
   Set Sound Speed 1,35000
   rem Loop Theme Sound
   Loop Sound 1
next t

Set text Size 20

Sprite 33,133,450,5
Sprite 34,383,450,5
Sprite 35,633,450,5

respawn:
Rem Draw Blue Enemies
For Enemy=1 to 10
	Sprite Enemy+2,Enemy*67,100,2
Next Enemy

Rem Draw Green Enemies
For Enemy=1 to 10
	Sprite Enemy+12,Enemy*67,200,3
Next Enemy

Rem Draw Purple Enemies
For Enemy=1 to 10
	Sprite Enemy+22,Enemy*67,300,4
Next Enemy

Rem Create and hide bullet for use in game
Sprite 2,0,0,7
Hide Sprite 2

For Enemy=1 to 10
	For Enemy2=3 to 3
		EnemyAttack(Enemy,Enemy2)=1
	Next Enemy2
next enemy

Rem main Loop (engine)
Do
	Rem Update the Blue Enemies position
	For Enemy=1 to 10
		EnemyPositionX(Enemy,1)=Sprite X(Enemy+2)
		If EnemyDir=1
			Sprite Enemy+2,EnemyPositionX(Enemy,1)+XMove,EnemyPositionY(1),2
		Endif
		If EnemyDir=0
			Sprite Enemy+2,EnemyPositionX(Enemy,1)-XMove,EnemyPositionY(1),2
		Endif
		If Sprite Visible(2)=1 And Sprite Visible(Enemy+2)=1 And Sprite Hit(2,Enemy+2)
			Hide Sprite Enemy+2
			BulletY=550
			Hide Sprite 2
			SoundSpeed=SoundSpeed+250
			Score=Score+3
			EnemiesLeft=EnemiesLeft+1
		endif
	Next Enemy
	Rem Update the Green Enemies position
	For Enemy=1 to 10
		EnemyPositionX(Enemy,2)=Sprite X(Enemy+12)
		If EnemyDir=1
			Sprite Enemy+12,EnemyPositionX(Enemy,2)+XMove,EnemyPositionY(2),3
		Endif
		If EnemyDir=0
			Sprite Enemy+12,EnemyPositionX(Enemy,2)-XMove,EnemyPositionY(2),3
		Endif
		If Sprite Visible(2)=1 And Sprite Visible(Enemy+12)=1 And Sprite Hit(2,Enemy+12)
			Hide Sprite Enemy+12
			BulletY=550
			Hide Sprite 2
			SoundSpeed=SoundSpeed+250
			Score=Score+2
			EnemiesLeft=EnemiesLeft+1
		endif
	Next Enemy
	Rem Update the Purple Enemies position
	For Enemy=1 to 10
		EnemyPositionX(Enemy,3)=Sprite X(Enemy+22)
		If EnemyDir=1
			Sprite Enemy+22,EnemyPositionX(Enemy,3)+XMove,EnemyPositionY(3),4
		Endif
		If EnemyDir=0
			Sprite Enemy+22,EnemyPositionX(Enemy,3)-XMove,EnemyPositionY(3),4
		Endif
		If Sprite Visible(2)=1 And Sprite Visible(Enemy+22)=1 And Sprite Hit(2,Enemy+22)
			Hide Sprite Enemy+22
			BulletY=550
			Hide Sprite 2
			SoundSpeed=SoundSpeed+250
			Score=Score+1
			EnemiesLeft=EnemiesLeft+1
		endif
	Next Enemy
   rem Exit the program
   If Escapekey()=1 Then End
   rem Create/Repoition Player Ship
   Sprite 1,PlayerX,PlayerY,1
   rem Move Player Ship
   If Leftkey()=1 And PlayerX>=0 Then PlayerX = PlayerX-4.5
   If Rightkey()=1 And PlayerX<=750 Then playerX = PlayerX+4.5
   rem Release bullet from ship
   If Spacekey()=1 Then Show Sprite 2 : Sprite 2,BulletX,BulletY,7 : Sprite 2,BulletX,BulletY,7
   If Sprite Visible(2)=1 Then BulletY=BulletY-8 : Sprite 2,BulletX,BulletY,7
   If BulletY<=0
   	Hide Sprite 2
   	BulletY=550
   Endif
   Rem Update Bullet X when bullet is hidden
   If Sprite Visible(2)=0
   	BulletX=PlayerX+20
   endif
   Rem Change the directional flag if Blue enemies reach edge of screen
   For Enemy=1 to 30
   	If Sprite X(Enemy+2)<=0 And Sprite Visible(Enemy+2)=1
   		EnemyDir=1
   	endif
   	If Sprite X(Enemy+2)>=756 And Sprite Visible(Enemy+2)=1
   		EnemyDir=0
   	Endif
   Next Enemy
   Rem When enemies reach edge of screen increase Y variable so enemies go down
   For Enemy=1 to 30
   	If Sprite X(Enemy+2)>=756 And Sprite Visible(Enemy+2)=1
   		EnemyY=EnemyY+YMove
   	endif
   	If Sprite X(Enemy+2)<=0 And Sprite Visible(Enemy+2)=1
			EnemyY=EnemyY+YMove
		Endif
   Next enemy
   For Enemy=1 to 30
   	If Sprite Y(Enemy+2)>450
   		End
   	Endif
   Next enemy
   If EnemiesLeft=30
      Gosub respawn
      For Enemy=1 to 30
         If Sprite Visible(Enemy+2)=0
            Show Sprite Enemy+2
         Endif
      next Enemy
      EnemiesLeft=0
   endif
   Rem our CLS equivalent
   fill memory mem_loc, 0, 2560000

   for s=0 to starquantity

      sx# = stars(s).x

      Rem works out where in memory to plot our dot!
      mem_y = int(stars(s).y)*(800*4)
      mem_x = (int(sx#)*4)
      mem_location = mem_x + mem_y

		Rem plots
      if mem_location > 1 and mem_location < 2560000
         write memblock dword 1, mem_location, stars(s).color
      endif

		Rem moves the star
      sx# = sx# - stars(s).speed
      if sx# < 0 then sx# = 800
      stars(s).x = sx#

   next s

	Rem This copies the pixel data from memory to the screen
   lock pixels
   copy memory get pixels pointer(), mem_loc, 2560000
   unlock pixels
   Rem speed up music
   Set Sound Speed 1,SoundSpeed
   text 10,10,"Score: "+Str$(Score)
   Rem refresh screen
   Sync
Loop

respawn:
Rem Draw Blue Enemies
For Enemy=1 to 10
	Sprite Enemy+2,Enemy*67,100,2
Next Enemy

Rem Draw Green Enemies
For Enemy=1 to 10
	Sprite Enemy+12,Enemy*67,200,3
Next Enemy

Rem Draw Purple Enemies
For Enemy=1 to 10
	Sprite Enemy+22,Enemy*67,300,4
Next Enemy

EnemyPositionY(1)=100
EnemyPositionY(2)=200
EnemyPositionY(3)=300
XMove=XMove+1
YMove=YMove+0.5
Return

Thanx

Back to top

Profile PM Email Website

Lampton Worm

22

Years of Service

User Offline

Joined: 4th Sep 2002

Location: United Kingdom

Posted: 23rd May 2004 16:25

Hi,

I can't remember, but in the original invaders did they only shoot if nothing was beneath them? Perhaps they shot whenever they liked and thier bullet collision was only detected against the player, not the other enemies, that would certainly be easier to implement

If not, you could try placing a dummy sprite down the indented path, and if it doesn't hit any other enemy, the path is clear, so fire a bullet. It would be quicker to have a single sprite object, that is quite long, and place that at an offset from the invader in question, that would save moving a sprite down the bullet path.

Pseudo...

for a=1 to enemies
place test sprite at enemy position
offset test sprite on y by 1/2 of its length
for b=1 to enemies
did test sprite collide with any other enemy?
if so...
enemy(b).path=not clear
else
enemy(b).path=clear
next b
if enemy(b).path=clear
enemy(b).canfire=yes
else
enemy(b).canfire=no
endif
next a

That's not tested btw, its just a theory

Another idea may be to store the enemies and their states in an array, then you could check the state of the enemy below the one that is about to fire, e.g. if the enemy below state is "killed" then the path is free. Just an idea though... I prefer the test sprite idea personally.

Cheers.

Back to top

Profile PM Website

GameMaker Jason

21

Years of Service

User Offline

Joined: 22nd Nov 2003

Location: UK

Posted: 24th May 2004 20:42

How can i make the test sprite thing. i'm unshore of it

Rem Project: Space Invaders
Rem Created: 16/05/2004 11:04:38

Rem ***** Main Source File *****

Rem Set the screen size and sync rate
Set Display Mode 800,600,32
Sync On : Sync Rate 120 : Hide Mouse

Rem Define Variables
PlayerX = 400-10
PlayerY = 550
BulletX = PlayerX+20
BulletY = 550
EnemyY=100
starquantity = 600
starlayers = 5
speedfactor# = 0.50
SoundSpeed=35000
Score=0
Alpha1=255
Alpha2=255
Alpha3=255
Dim EnemyPositionX(10,3)
EnemiesLeft=0
XMove=2
YMove#=2

Rem Type for the move background
type starfield

X AS FLOAT
   Y AS FLOAT
   Z AS INTEGER
   speed AS FLOAT
   color AS DWORD

endtype

Rem Array of stars
dim stars(starquantity) as starfield

rem Create the location of the stars
for s=0 to starquantity

stars(s).x = rnd(800)
   stars(s).y = rnd(800)
   stars(s).z = int(s/(starquantity/starlayers))+1
   stars(s).speed = stars(s).z * speedfactor#
   temp_col = (255/starlayers) * stars(s).z
   stars(s).color = rgb(rnd(255),rnd(255),rnd(255))

next s

Rem our memblock - this is calculated from the following: screen X * screen Y * 4 (bytes per pixel)
make memblock 1,2560000
mem_loc AS DWORD
mem_loc = get memblock ptr(1)

Rem Load media in loop
For t=1 to 1
   rem Load image
   Load Image "images\ship1.png",1
   Load Image "images\bluenemy.png",2
   Load Image "images\grnenemy.png",3
   Load Image "images\purpenemy.png",4
   Load Image "images\Shield.png",5
   Load Image "images\bullete.png",6
   Load Image "images\bulletp.png",7
   Load Image "images\ship2.png",8
   rem load Theme Sound
   Load Sound "Music\Space Invaders Background.WAV",1
   rem Set the sound speed
   Set Sound Speed 1,35000
   rem Loop Theme Sound
   Loop Sound 1
next t

Set text Size 20

Sprite 33,133,450,5
Sprite 34,383,450,5
Sprite 35,633,450,5

respawn:
Rem Draw Blue Enemies
For Enemy=1 to 10
	Sprite Enemy+2,Enemy*67,100,2
Next Enemy

Rem Draw Green Enemies
For Enemy=1 to 10
	Sprite Enemy+12,Enemy*67,200,3
Next Enemy

Rem Draw Purple Enemies
For Enemy=1 to 10
	Sprite Enemy+22,Enemy*67,300,4
Next Enemy

Rem Create and hide bullet for use in game
Sprite 2,0,0,7
Hide Sprite 2

Rem main Loop (engine)
Do
	Rem Update the Blue Enemies position
	For Enemy=1 to 10
		EnemyPositionX(Enemy,1)=Sprite X(Enemy+2)
		If EnemyDir=1
			Sprite Enemy+2,EnemyPositionX(Enemy,1)+XMove,EnemyY,2
		Endif
		If EnemyDir=0
			Sprite Enemy+2,EnemyPositionX(Enemy,1)-XMove,EnemyY,2
		Endif
		If Sprite Visible(2)=1 And Sprite Visible(Enemy+2)=1 And Sprite Hit(2,Enemy+2)
			Hide Sprite Enemy+2
			BulletY=550
			Hide Sprite 2
			SoundSpeed=SoundSpeed+250
			Score=Score+3
			EnemiesLeft=EnemiesLeft+1
		endif
	Next Enemy
	Rem Update the Green Enemies position
	For Enemy=1 to 10
		EnemyPositionX(Enemy,2)=Sprite X(Enemy+12)
		If EnemyDir=1
			Sprite Enemy+12,EnemyPositionX(Enemy,2)+XMove,EnemyY+100,3
		Endif
		If EnemyDir=0
			Sprite Enemy+12,EnemyPositionX(Enemy,2)-XMove,EnemyY+100,3
		Endif
		If Sprite Visible(2)=1 And Sprite Visible(Enemy+12)=1 And Sprite Hit(2,Enemy+12)
			Hide Sprite Enemy+12
			BulletY=550
			Hide Sprite 2
			SoundSpeed=SoundSpeed+250
			Score=Score+2
			EnemiesLeft=EnemiesLeft+1
		endif
	Next Enemy
	Rem Update the Purple Enemies position
	For Enemy=1 to 10
		EnemyPositionX(Enemy,3)=Sprite X(Enemy+22)
		If EnemyDir=1
			Sprite Enemy+22,EnemyPositionX(Enemy,3)+XMove,EnemyY+200,4
		Endif
		If EnemyDir=0
			Sprite Enemy+22,EnemyPositionX(Enemy,3)-XMove,EnemyY+200,4
		Endif
		If Sprite Visible(2)=1 And Sprite Visible(Enemy+22)=1 And Sprite Hit(2,Enemy+22)
			Hide Sprite Enemy+22
			BulletY=550
			Hide Sprite 2
			SoundSpeed=SoundSpeed+250
			Score=Score+1
			EnemiesLeft=EnemiesLeft+1
		endif
	Next Enemy
   rem Exit the program
   If Escapekey()=1 Then End
   rem Create/Repoition Player Ship
   Sprite 1,PlayerX,PlayerY,1
   rem Move Player Ship
   If Leftkey()=1 And PlayerX>=0 Then PlayerX = PlayerX-4.5
   If Rightkey()=1 And PlayerX<=750 Then playerX = PlayerX+4.5
   rem Release bullet from ship
   If Spacekey()=1 Then Show Sprite 2 : Sprite 2,BulletX,BulletY,7 : Sprite 2,BulletX,BulletY,7
   If Sprite Visible(2)=1 Then BulletY=BulletY-8 : Sprite 2,BulletX,BulletY,7
   If BulletY<=0
   	Hide Sprite 2
   	BulletY=550
   Endif
   Rem Update Bullet X when bullet is hidden
   If Sprite Visible(2)=0
   	BulletX=PlayerX+20
   endif
   Rem Change the directional flag if Blue enemies reach edge of screen
   For Enemy=1 to 30
   	If Sprite X(Enemy+2)<=0 And Sprite Visible(Enemy+2)=1
   		EnemyDir=1
   	endif
   	If Sprite X(Enemy+2)>=756 And Sprite Visible(Enemy+2)=1
   		EnemyDir=0
   	Endif
   Next Enemy
   Rem When enemies reach edge of screen increase Y variable so enemies go down
   For Enemy=1 to 30
   	For Enemy2=1 to 3
   		If Sprite X(Enemy+2)>=756 And Sprite Visible(Enemy+2)=1
   			EnemyY=EnemyY+YMove#
   		endif
   		If Sprite X(Enemy+2)<=0 And Sprite Visible(Enemy+2)=1
				EnemyY=EnemyY+YMove#
   		Endif
   	next Enemy2
   Next enemy
   For Enemy=1 to 30
   	If Sprite Y(Enemy+2)>450
   		End
   	Endif
   Next enemy
   If EnemiesLeft=30
      Gosub respawn
      For Enemy=1 to 30
         If Sprite Visible(Enemy+2)=0
            Show Sprite Enemy+2
         Endif
      next Enemy
      EnemiesLeft=0
   endif
   Rem our CLS equivalent
   fill memory mem_loc, 0, 2560000

for s=0 to starquantity

sx# = stars(s).x

Rem works out where in memory to plot our dot!
      mem_y = int(stars(s).y)*(800*4)
      mem_x = (int(sx#)*4)
      mem_location = mem_x + mem_y

Rem plots
      if mem_location > 1 and mem_location < 2560000
         write memblock dword 1, mem_location, stars(s).color
      endif

Rem moves the star
      sx# = sx# - stars(s).speed
      if sx# < 0 then sx# = 800
      stars(s).x = sx#

next s

Rem This copies the pixel data from memory to the screen
   lock pixels
   copy memory get pixels pointer(), mem_loc, 2560000
   unlock pixels
   Rem speed up music
   Set Sound Speed 1,SoundSpeed
   text 10,10,"Score: "+Str$(Score)
   Rem refresh screen
   Sync
Loop

respawn:
Rem Draw Blue Enemies
For Enemy=1 to 10
	Sprite Enemy+2,Enemy*67,100,2
Next Enemy

Rem Draw Green Enemies
For Enemy=1 to 10
	Sprite Enemy+12,Enemy*67,200,3
Next Enemy

Rem Draw Purple Enemies
For Enemy=1 to 10
	Sprite Enemy+22,Enemy*67,300,4
Next Enemy

EnemyY=100
XMove=XMove+1
YMove=YMove+0.5
Return

Rem Project: Space Invaders
Rem Created: 16/05/2004 11:04:38

Rem ***** Main Source File *****

Rem Set the screen size and sync rate
Set Display Mode 800,600,32
Sync On : Sync Rate 120 : Hide Mouse

Rem Define Variables
PlayerX = 400-10
PlayerY = 550
BulletX = PlayerX+20
BulletY = 550
EnemyY=100
starquantity = 600
starlayers = 5
speedfactor# = 0.50
SoundSpeed=35000
Score=0
Alpha1=255
Alpha2=255
Alpha3=255
Dim EnemyPositionX(10,3)
EnemiesLeft=0
XMove=2
YMove#=2

Rem Type for the move background
type starfield

   X AS FLOAT
   Y AS FLOAT
   Z AS INTEGER
   speed AS FLOAT
   color AS DWORD

endtype

Rem Array of stars
dim stars(starquantity) as starfield

rem Create the location of the stars
for s=0 to starquantity

   stars(s).x = rnd(800)
   stars(s).y = rnd(800)
   stars(s).z = int(s/(starquantity/starlayers))+1
   stars(s).speed = stars(s).z * speedfactor#
   temp_col = (255/starlayers) * stars(s).z
   stars(s).color = rgb(rnd(255),rnd(255),rnd(255))

next s

Rem our memblock - this is calculated from the following: screen X * screen Y * 4 (bytes per pixel)
make memblock 1,2560000
mem_loc AS DWORD
mem_loc = get memblock ptr(1)

Rem Load media in loop
For t=1 to 1
   rem Load image
   Load Image "images\ship1.png",1
   Load Image "images\bluenemy.png",2
   Load Image "images\grnenemy.png",3
   Load Image "images\purpenemy.png",4
   Load Image "images\Shield.png",5
   Load Image "images\bullete.png",6
   Load Image "images\bulletp.png",7
   Load Image "images\ship2.png",8
   rem load Theme Sound
   Load Sound "Music\Space Invaders Background.WAV",1
   rem Set the sound speed
   Set Sound Speed 1,35000
   rem Loop Theme Sound
   Loop Sound 1
next t

Set text Size 20

Sprite 33,133,450,5
Sprite 34,383,450,5
Sprite 35,633,450,5

respawn:
Rem Draw Blue Enemies
For Enemy=1 to 10
	Sprite Enemy+2,Enemy*67,100,2
Next Enemy

Rem Draw Green Enemies
For Enemy=1 to 10
	Sprite Enemy+12,Enemy*67,200,3
Next Enemy

Rem Draw Purple Enemies
For Enemy=1 to 10
	Sprite Enemy+22,Enemy*67,300,4
Next Enemy

Rem Create and hide bullet for use in game
Sprite 2,0,0,7
Hide Sprite 2

Rem main Loop (engine)
Do
	Rem Update the Blue Enemies position
	For Enemy=1 to 10
		EnemyPositionX(Enemy,1)=Sprite X(Enemy+2)
		If EnemyDir=1
			Sprite Enemy+2,EnemyPositionX(Enemy,1)+XMove,EnemyY,2
		Endif
		If EnemyDir=0
			Sprite Enemy+2,EnemyPositionX(Enemy,1)-XMove,EnemyY,2
		Endif
		If Sprite Visible(2)=1 And Sprite Visible(Enemy+2)=1 And Sprite Hit(2,Enemy+2)
			Hide Sprite Enemy+2
			BulletY=550
			Hide Sprite 2
			SoundSpeed=SoundSpeed+250
			Score=Score+3
			EnemiesLeft=EnemiesLeft+1
		endif
	Next Enemy
	Rem Update the Green Enemies position
	For Enemy=1 to 10
		EnemyPositionX(Enemy,2)=Sprite X(Enemy+12)
		If EnemyDir=1
			Sprite Enemy+12,EnemyPositionX(Enemy,2)+XMove,EnemyY+100,3
		Endif
		If EnemyDir=0
			Sprite Enemy+12,EnemyPositionX(Enemy,2)-XMove,EnemyY+100,3
		Endif
		If Sprite Visible(2)=1 And Sprite Visible(Enemy+12)=1 And Sprite Hit(2,Enemy+12)
			Hide Sprite Enemy+12
			BulletY=550
			Hide Sprite 2
			SoundSpeed=SoundSpeed+250
			Score=Score+2
			EnemiesLeft=EnemiesLeft+1
		endif
	Next Enemy
	Rem Update the Purple Enemies position
	For Enemy=1 to 10
		EnemyPositionX(Enemy,3)=Sprite X(Enemy+22)
		If EnemyDir=1
			Sprite Enemy+22,EnemyPositionX(Enemy,3)+XMove,EnemyY+200,4
		Endif
		If EnemyDir=0
			Sprite Enemy+22,EnemyPositionX(Enemy,3)-XMove,EnemyY+200,4
		Endif
		If Sprite Visible(2)=1 And Sprite Visible(Enemy+22)=1 And Sprite Hit(2,Enemy+22)
			Hide Sprite Enemy+22
			BulletY=550
			Hide Sprite 2
			SoundSpeed=SoundSpeed+250
			Score=Score+1
			EnemiesLeft=EnemiesLeft+1
		endif
	Next Enemy
   rem Exit the program
   If Escapekey()=1 Then End
   rem Create/Repoition Player Ship
   Sprite 1,PlayerX,PlayerY,1
   rem Move Player Ship
   If Leftkey()=1 And PlayerX>=0 Then PlayerX = PlayerX-4.5
   If Rightkey()=1 And PlayerX<=750 Then playerX = PlayerX+4.5
   rem Release bullet from ship
   If Spacekey()=1 Then Show Sprite 2 : Sprite 2,BulletX,BulletY,7 : Sprite 2,BulletX,BulletY,7
   If Sprite Visible(2)=1 Then BulletY=BulletY-8 : Sprite 2,BulletX,BulletY,7
   If BulletY<=0
   	Hide Sprite 2
   	BulletY=550
   Endif
   Rem Update Bullet X when bullet is hidden
   If Sprite Visible(2)=0
   	BulletX=PlayerX+20
   endif
   Rem Change the directional flag if Blue enemies reach edge of screen
   For Enemy=1 to 30
   	If Sprite X(Enemy+2)<=0 And Sprite Visible(Enemy+2)=1
   		EnemyDir=1
   	endif
   	If Sprite X(Enemy+2)>=756 And Sprite Visible(Enemy+2)=1
   		EnemyDir=0
   	Endif
   Next Enemy
   Rem When enemies reach edge of screen increase Y variable so enemies go down
   For Enemy=1 to 30
   	For Enemy2=1 to 3
   		If Sprite X(Enemy+2)>=756 And Sprite Visible(Enemy+2)=1
   			EnemyY=EnemyY+YMove#
   		endif
   		If Sprite X(Enemy+2)<=0 And Sprite Visible(Enemy+2)=1
				EnemyY=EnemyY+YMove#
   		Endif
   	next Enemy2
   Next enemy
   For Enemy=1 to 30
   	If Sprite Y(Enemy+2)>450
   		End
   	Endif
   Next enemy
   If EnemiesLeft=30
      Gosub respawn
      For Enemy=1 to 30
         If Sprite Visible(Enemy+2)=0
            Show Sprite Enemy+2
         Endif
      next Enemy
      EnemiesLeft=0
   endif
   Rem our CLS equivalent
   fill memory mem_loc, 0, 2560000

   for s=0 to starquantity

      sx# = stars(s).x

      Rem works out where in memory to plot our dot!
      mem_y = int(stars(s).y)*(800*4)
      mem_x = (int(sx#)*4)
      mem_location = mem_x + mem_y

		Rem plots
      if mem_location > 1 and mem_location < 2560000
         write memblock dword 1, mem_location, stars(s).color
      endif

		Rem moves the star
      sx# = sx# - stars(s).speed
      if sx# < 0 then sx# = 800
      stars(s).x = sx#

   next s

	Rem This copies the pixel data from memory to the screen
   lock pixels
   copy memory get pixels pointer(), mem_loc, 2560000
   unlock pixels
   Rem speed up music
   Set Sound Speed 1,SoundSpeed
   text 10,10,"Score: "+Str$(Score)
   Rem refresh screen
   Sync
Loop

respawn:
Rem Draw Blue Enemies
For Enemy=1 to 10
	Sprite Enemy+2,Enemy*67,100,2
Next Enemy

Rem Draw Green Enemies
For Enemy=1 to 10
	Sprite Enemy+12,Enemy*67,200,3
Next Enemy

Rem Draw Purple Enemies
For Enemy=1 to 10
	Sprite Enemy+22,Enemy*67,300,4
Next Enemy

EnemyY=100
XMove=XMove+1
YMove=YMove+0.5
Return

Thanx

Back to top

Profile PM Email Website

Lampton Worm

22

Years of Service

User Offline

Joined: 4th Sep 2002

Location: United Kingdom

Posted: 25th May 2004 11:56

Hi,

It would just be a normal sprite, but hidden (you may want to leave it visible while you implement it though, it'll be easier to see what is going on). As with most things, probably best to break this down into smaller chunks, and work on them one by one, say...

1) Create test sprite, e.g.
box 0,0,8,640
get image 999,0,0,8,640
sprite 999,0,0,999

2) Create a loop to position the test sprite at the live alien coords

3) An an offset so the test image is displayed as if it were a ray casting downwards (its just a sprite collision check down the path that a potential bullet would follow).

4) Add the collision check

5) Add collision response behaviour

6) Hide the test sprite

Hope it helps, sorry I can't drop you any code, v-busy with work and study this week

Cheers.

Back to top

Profile PM Website

GameMaker Jason

21

Years of Service

User Offline

Joined: 22nd Nov 2003

Location: UK

Posted: 26th May 2004 20:25

I am now tring to make make alien shot when the timer reaches 0 then reset it to a random time between 2-10 seconds but i dont know how to make my variable count down 1 everysecond.

Rem Project: Space Invaders
Rem Created: 16/05/2004 11:04:38

Rem ***** Main Source File *****

Rem Set the screen size and sync rate
Set Display Mode 800,600,32
Sync On : Sync Rate 120 : Hide Mouse
Randomize Timer()

Rem Define Variables
PlayerX = 400-10
PlayerY = 550
BulletX = PlayerX+20
BulletY = 550
EnemyY=100
starquantity = 600
starlayers = 5
speedfactor# = 0.50
SoundSpeed=35000
Score=0
Alpha1=255
Alpha2=255
Alpha3=255
Dim EnemyPositionX(10,3)
Dim EnemyAttack(10,3)
Dim EnemyPositionY(3)
Dim EnemyBulletY(10)
Dim EnemyBulletX(10)
Dim EnemyBulletFire(10)
EnemyPositionY(1)=100
EnemyPositionY(2)=200
EnemyPositionY(3)=300
EnemiesLeft=0
XMove=2
YMove#=2

For EnemyFire=1 to 10
	EnemyBulletFire(Enemy)= Rem set to random time to wait
next enemyfire

Rem Type for the move background
type starfield

X AS FLOAT
   Y AS FLOAT
   Z AS INTEGER
   speed AS FLOAT
   color AS DWORD

endtype

Rem Array of stars
dim stars(starquantity) as starfield

rem Create the location of the stars
for s=0 to starquantity

stars(s).x = rnd(800)
   stars(s).y = rnd(800)
   stars(s).z = int(s/(starquantity/starlayers))+1
   stars(s).speed = stars(s).z * speedfactor#
   temp_col = (255/starlayers) * stars(s).z
   stars(s).color = rgb(rnd(255),rnd(255),rnd(255))

next s

Rem our memblock - this is calculated from the following: screen X * screen Y * 4 (bytes per pixel)
make memblock 1,2560000
mem_loc AS DWORD
mem_loc = get memblock ptr(1)

Rem Load media in loop
For t=1 to 1
   rem Load image
   Load Image "images\ship1.png",1
   Load Image "images\bluenemy.png",2
   Load Image "images\grnenemy.png",3
   Load Image "images\purpenemy.png",4
   Load Image "images\Shield.png",5
   Load Image "images\bullete.png",6
   Load Image "images\bulletp.png",7
   Load Image "images\ship2.png",8
   rem load Theme Sound
   Load Sound "Music\Space Invaders Background.WAV",1
   rem Set the sound speed
   Set Sound Speed 1,35000
   rem Loop Theme Sound
   Loop Sound 1
next t

Set text Size 20

Sprite 33,133,450,5
Sprite 34,383,450,5
Sprite 35,633,450,5

Rem Draw Blue Enemies
For Enemy=1 to 10
	Sprite Enemy+2,Enemy*67,100,2
Next Enemy

Rem Draw Green Enemies
For Enemy=1 to 10
	Sprite Enemy+12,Enemy*67,200,3
Next Enemy

Rem Draw Purple Enemies
For Enemy=1 to 10
	Sprite Enemy+22,Enemy*67,300,4
Next Enemy

Rem Create and hide bullet for use in game
Sprite 2,0,0,7
Hide Sprite 2

For Enemy=1 to 10
	For Enemy2=3 to 3
		EnemyAttack(Enemy,Enemy2)=1
	next enemy2
next enemy

For Enemy=1 to 10
	For Enemy2=1 to 3
		If EnemyAttack(Enemy,Enemy2)=1
			EnemyBulletY(Enemy)=EnemyPositionY(Enemy2)+25
		endif
	next enemy2
next enemy

For Enemy=1 to 10
	For Enemy2=1 to 3
		If EnemyAttack(Enemy,Enemy2)=1
			EnemyBulletX(Enemy)=EnemyPositionX(Enemy,Enemy2)+21
		endif
	next enemy2
next enemy

Rem main Loop (engine)
Do
	Rem Update the Blue Enemies position
	For Enemy=1 to 10
		EnemyPositionX(Enemy,1)=Sprite X(Enemy+2)
		If EnemyDir=1
			Sprite Enemy+2,EnemyPositionX(Enemy,1)+XMove,EnemyPositionY(1),2
		Endif
		If EnemyDir=0
			Sprite Enemy+2,EnemyPositionX(Enemy,1)-XMove,EnemyPositionY(1),2
		Endif
		If Sprite Visible(2)=1 And Sprite Visible(Enemy+2)=1 And Sprite Hit(2,Enemy+2)
			Hide Sprite Enemy+2
			BulletY=550
			Hide Sprite 2
			SoundSpeed=SoundSpeed+250
			Score=Score+3
			EnemiesLeft=EnemiesLeft+1
		endif
	Next Enemy
	Rem Update the Green Enemies position
	For Enemy=1 to 10
		EnemyPositionX(Enemy,2)=Sprite X(Enemy+12)
		If EnemyDir=1
			Sprite Enemy+12,EnemyPositionX(Enemy,2)+XMove,EnemyPositionY(2),3
		Endif
		If EnemyDir=0
			Sprite Enemy+12,EnemyPositionX(Enemy,2)-XMove,EnemyPositionY(2),3
		Endif
		If Sprite Visible(2)=1 And Sprite Visible(Enemy+12)=1 And Sprite Hit(2,Enemy+12)
			Hide Sprite Enemy+12
			BulletY=550
			Hide Sprite 2
			SoundSpeed=SoundSpeed+250
			Score=Score+2
			EnemiesLeft=EnemiesLeft+1
		endif
	Next Enemy
	Rem Update the Purple Enemies position
	For Enemy=1 to 10
		EnemyPositionX(Enemy,3)=Sprite X(Enemy+22)
		If EnemyDir=1
			Sprite Enemy+22,EnemyPositionX(Enemy,3)+XMove,EnemyPositionY(3),4
		Endif
		If EnemyDir=0
			Sprite Enemy+22,EnemyPositionX(Enemy,3)-XMove,EnemyPositionY(3),4
		Endif
		If Sprite Visible(2)=1 And Sprite Visible(Enemy+22)=1 And Sprite Hit(2,Enemy+22)
			Hide Sprite Enemy+22
			BulletY=550
			Hide Sprite 2
			SoundSpeed=SoundSpeed+250
			Score=Score+1
			EnemiesLeft=EnemiesLeft+1
		endif
	Next Enemy
   rem Exit the program
   If Escapekey()=1 Then End
   rem Create/Repoition Player Ship
   Sprite 1,PlayerX,PlayerY,1
   rem Move Player Ship
   If Leftkey()=1 And PlayerX>=4.5 Then PlayerX = PlayerX-4.5
   If Rightkey()=1 And PlayerX<=745.5 Then playerX = PlayerX+4.5
   rem Release bullet from ship
   If Spacekey()=1 Then Show Sprite 2 : Sprite 2,BulletX,BulletY,7 : Sprite 2,BulletX,BulletY,7
   If Sprite Visible(2)=1 Then BulletY=BulletY-8 : Sprite 2,BulletX,BulletY,7
   If BulletY<=0
   	Hide Sprite 2
   	BulletY=550
   Endif
   Rem Update Bullet X when bullet is hidden
   If Sprite Visible(2)=0
   	BulletX=PlayerX+20
   endif
   Rem Change the directional flag if Blue enemies reach edge of screen
   For Enemy=1 to 30
   	If Sprite X(Enemy+2)<=0 And Sprite Visible(Enemy+2)=1
   		EnemyDir=1
   	endif
   	If Sprite X(Enemy+2)>=756 And Sprite Visible(Enemy+2)=1
   		EnemyDir=0
   	Endif
   Next Enemy
   Rem When enemies reach edge of screen increase Y variable so enemies go down
   For Enemy=1 to 30
   	For Enemy2=1 to 3
   		If Sprite X(Enemy+2)>=756 And Sprite Visible(Enemy+2)=1
   			EnemyPositionY(Enemy2)=EnemyPositionY(Enemy2)+YMove#
   		endif
   		If Sprite X(Enemy+2)<=0 And Sprite Visible(Enemy+2)=1
				EnemyPositionY(Enemy2)=EnemyPositionY(Enemy2)+YMove#
   		Endif
   	next Enemy2
   Next enemy
   For Enemy=1 to 30
   	If Sprite Y(Enemy+2)=>500
   		Cls
   		Center Text 400,300,"Game Over!"
   		Wait 3000
   		End
   	Endif
   Next enemy
   If EnemiesLeft=30
      Gosub respawn
      For Enemy=1 to 30
         If Sprite Visible(Enemy+2)=0
            Show Sprite Enemy+2
         Endif
      next Enemy
      EnemiesLeft=0
   endif
   For Enemy=1 to 10
   	For Enemy2=1 to 3
   		If Sprite Visible(Enemy+2)=0
   			EnemyAttack(Enemy,Enemy2)=0
   			If Enemy2<3
   				EnemyAttack(Enemy,Enemy2+1)=1
   			endif
   		endif
   	next enemy2
   next enemy
   For Enemy=1 to 10
   	For Enemy2=1 to 3
   		If EnemyAttack(Enemy,Enemy2)=1
   			Sprite Enemy+90,EnemyPositionX(Enemy,Enemy2)+20,EnemyPositionY(Enemy2),6
   		endif
   	next enemy2
   next enemy
   For Enemy=1 to 10
   	EnemyBulletFire(Enemy)=EnemyBulletFire(Enemy)-1
   next enemy
   For Enemy=1 to 10
   	If EnemyBulletFire(Enemy)=0
   		Show Sprite Enemy+90
   	endif
   	If EnemyBulletFire(Enemy)=0
   		EnemyBulletFire(Enemy)= Rem set to random time to wait
   	endif
   next enemy
   For Enemy=1 to 10
		For Enemy2=1 to 3
			If EnemyAttack(Enemy,Enemy2)=1
				EnemyBulletY(Enemy)=EnemyPositionY(Enemy2)+25
			endif
		next enemy2
	next enemy
	For Enemy=1 to 10
		For Enemy2=1 to 3
			If EnemyAttack(Enemy,Enemy2)=1
				EnemyBulletX(Enemy)=EnemyPositionX(Enemy,Enemy2)+21
			endif
		next enemy2
	next enemy
   Rem our CLS equivalent
   fill memory mem_loc, 0, 2560000

for s=0 to starquantity

sx# = stars(s).x

Rem works out where in memory to plot our dot!
      mem_y = int(stars(s).y)*(800*4)
      mem_x = (int(sx#)*4)
      mem_location = mem_x + mem_y

Rem plots
      if mem_location > 1 and mem_location < 2560000
         write memblock dword 1, mem_location, stars(s).color
      endif

Rem moves the star
      sx# = sx# - stars(s).speed
      if sx# < 0 then sx# = 800
      stars(s).x = sx#

next s

Rem This copies the pixel data from memory to the screen
   lock pixels
   copy memory get pixels pointer(), mem_loc, 2560000
   unlock pixels
   Rem speed up music
   Set Sound Speed 1,SoundSpeed
   text 10,10,"Score: "+Str$(Score)
   Rem refresh screen
   Sync
Loop

respawn:
Rem Draw Blue Enemies
For Enemy=1 to 10
	Sprite Enemy+2,Enemy*67,100,2
Next Enemy

Rem Draw Green Enemies
For Enemy=1 to 10
	Sprite Enemy+12,Enemy*67,200,3
Next Enemy

Rem Draw Purple Enemies
For Enemy=1 to 10
	Sprite Enemy+22,Enemy*67,300,4
Next Enemy

EnemyPositionY(1)=100
EnemyPositionY(2)=200
EnemyPositionY(3)=300
XMove=XMove+1
YMove=YMove+0.5
SoundSpeed=35000
Return

Rem Project: Space Invaders
Rem Created: 16/05/2004 11:04:38

Rem ***** Main Source File *****

Rem Set the screen size and sync rate
Set Display Mode 800,600,32
Sync On : Sync Rate 120 : Hide Mouse
Randomize Timer()

Rem Define Variables
PlayerX = 400-10
PlayerY = 550
BulletX = PlayerX+20
BulletY = 550
EnemyY=100
starquantity = 600
starlayers = 5
speedfactor# = 0.50
SoundSpeed=35000
Score=0
Alpha1=255
Alpha2=255
Alpha3=255
Dim EnemyPositionX(10,3)
Dim EnemyAttack(10,3)
Dim EnemyPositionY(3)
Dim EnemyBulletY(10)
Dim EnemyBulletX(10)
Dim EnemyBulletFire(10)
EnemyPositionY(1)=100
EnemyPositionY(2)=200
EnemyPositionY(3)=300
EnemiesLeft=0
XMove=2
YMove#=2

For EnemyFire=1 to 10
	EnemyBulletFire(Enemy)= Rem set to random time to wait
next enemyfire

Rem Type for the move background
type starfield

   X AS FLOAT
   Y AS FLOAT
   Z AS INTEGER
   speed AS FLOAT
   color AS DWORD

endtype

Rem Array of stars
dim stars(starquantity) as starfield

rem Create the location of the stars
for s=0 to starquantity

   stars(s).x = rnd(800)
   stars(s).y = rnd(800)
   stars(s).z = int(s/(starquantity/starlayers))+1
   stars(s).speed = stars(s).z * speedfactor#
   temp_col = (255/starlayers) * stars(s).z
   stars(s).color = rgb(rnd(255),rnd(255),rnd(255))

next s

Rem our memblock - this is calculated from the following: screen X * screen Y * 4 (bytes per pixel)
make memblock 1,2560000
mem_loc AS DWORD
mem_loc = get memblock ptr(1)

Rem Load media in loop
For t=1 to 1
   rem Load image
   Load Image "images\ship1.png",1
   Load Image "images\bluenemy.png",2
   Load Image "images\grnenemy.png",3
   Load Image "images\purpenemy.png",4
   Load Image "images\Shield.png",5
   Load Image "images\bullete.png",6
   Load Image "images\bulletp.png",7
   Load Image "images\ship2.png",8
   rem load Theme Sound
   Load Sound "Music\Space Invaders Background.WAV",1
   rem Set the sound speed
   Set Sound Speed 1,35000
   rem Loop Theme Sound
   Loop Sound 1
next t

Set text Size 20

Sprite 33,133,450,5
Sprite 34,383,450,5
Sprite 35,633,450,5

Rem Draw Blue Enemies
For Enemy=1 to 10
	Sprite Enemy+2,Enemy*67,100,2
Next Enemy

Rem Draw Green Enemies
For Enemy=1 to 10
	Sprite Enemy+12,Enemy*67,200,3
Next Enemy

Rem Draw Purple Enemies
For Enemy=1 to 10
	Sprite Enemy+22,Enemy*67,300,4
Next Enemy

Rem Create and hide bullet for use in game
Sprite 2,0,0,7
Hide Sprite 2

For Enemy=1 to 10
	For Enemy2=3 to 3
		EnemyAttack(Enemy,Enemy2)=1
	next enemy2
next enemy

For Enemy=1 to 10
	For Enemy2=1 to 3
		If EnemyAttack(Enemy,Enemy2)=1
			EnemyBulletY(Enemy)=EnemyPositionY(Enemy2)+25
		endif
	next enemy2
next enemy

For Enemy=1 to 10
	For Enemy2=1 to 3
		If EnemyAttack(Enemy,Enemy2)=1
			EnemyBulletX(Enemy)=EnemyPositionX(Enemy,Enemy2)+21
		endif
	next enemy2
next enemy

Rem main Loop (engine)
Do
	Rem Update the Blue Enemies position
	For Enemy=1 to 10
		EnemyPositionX(Enemy,1)=Sprite X(Enemy+2)
		If EnemyDir=1
			Sprite Enemy+2,EnemyPositionX(Enemy,1)+XMove,EnemyPositionY(1),2
		Endif
		If EnemyDir=0
			Sprite Enemy+2,EnemyPositionX(Enemy,1)-XMove,EnemyPositionY(1),2
		Endif
		If Sprite Visible(2)=1 And Sprite Visible(Enemy+2)=1 And Sprite Hit(2,Enemy+2)
			Hide Sprite Enemy+2
			BulletY=550
			Hide Sprite 2
			SoundSpeed=SoundSpeed+250
			Score=Score+3
			EnemiesLeft=EnemiesLeft+1
		endif
	Next Enemy
	Rem Update the Green Enemies position
	For Enemy=1 to 10
		EnemyPositionX(Enemy,2)=Sprite X(Enemy+12)
		If EnemyDir=1
			Sprite Enemy+12,EnemyPositionX(Enemy,2)+XMove,EnemyPositionY(2),3
		Endif
		If EnemyDir=0
			Sprite Enemy+12,EnemyPositionX(Enemy,2)-XMove,EnemyPositionY(2),3
		Endif
		If Sprite Visible(2)=1 And Sprite Visible(Enemy+12)=1 And Sprite Hit(2,Enemy+12)
			Hide Sprite Enemy+12
			BulletY=550
			Hide Sprite 2
			SoundSpeed=SoundSpeed+250
			Score=Score+2
			EnemiesLeft=EnemiesLeft+1
		endif
	Next Enemy
	Rem Update the Purple Enemies position
	For Enemy=1 to 10
		EnemyPositionX(Enemy,3)=Sprite X(Enemy+22)
		If EnemyDir=1
			Sprite Enemy+22,EnemyPositionX(Enemy,3)+XMove,EnemyPositionY(3),4
		Endif
		If EnemyDir=0
			Sprite Enemy+22,EnemyPositionX(Enemy,3)-XMove,EnemyPositionY(3),4
		Endif
		If Sprite Visible(2)=1 And Sprite Visible(Enemy+22)=1 And Sprite Hit(2,Enemy+22)
			Hide Sprite Enemy+22
			BulletY=550
			Hide Sprite 2
			SoundSpeed=SoundSpeed+250
			Score=Score+1
			EnemiesLeft=EnemiesLeft+1
		endif
	Next Enemy
   rem Exit the program
   If Escapekey()=1 Then End
   rem Create/Repoition Player Ship
   Sprite 1,PlayerX,PlayerY,1
   rem Move Player Ship
   If Leftkey()=1 And PlayerX>=4.5 Then PlayerX = PlayerX-4.5
   If Rightkey()=1 And PlayerX<=745.5 Then playerX = PlayerX+4.5
   rem Release bullet from ship
   If Spacekey()=1 Then Show Sprite 2 : Sprite 2,BulletX,BulletY,7 : Sprite 2,BulletX,BulletY,7
   If Sprite Visible(2)=1 Then BulletY=BulletY-8 : Sprite 2,BulletX,BulletY,7
   If BulletY<=0
   	Hide Sprite 2
   	BulletY=550
   Endif
   Rem Update Bullet X when bullet is hidden
   If Sprite Visible(2)=0
   	BulletX=PlayerX+20
   endif
   Rem Change the directional flag if Blue enemies reach edge of screen
   For Enemy=1 to 30
   	If Sprite X(Enemy+2)<=0 And Sprite Visible(Enemy+2)=1
   		EnemyDir=1
   	endif
   	If Sprite X(Enemy+2)>=756 And Sprite Visible(Enemy+2)=1
   		EnemyDir=0
   	Endif
   Next Enemy
   Rem When enemies reach edge of screen increase Y variable so enemies go down
   For Enemy=1 to 30
   	For Enemy2=1 to 3
   		If Sprite X(Enemy+2)>=756 And Sprite Visible(Enemy+2)=1
   			EnemyPositionY(Enemy2)=EnemyPositionY(Enemy2)+YMove#
   		endif
   		If Sprite X(Enemy+2)<=0 And Sprite Visible(Enemy+2)=1
				EnemyPositionY(Enemy2)=EnemyPositionY(Enemy2)+YMove#
   		Endif
   	next Enemy2
   Next enemy
   For Enemy=1 to 30
   	If Sprite Y(Enemy+2)=>500
   		Cls
   		Center Text 400,300,"Game Over!"
   		Wait 3000
   		End
   	Endif
   Next enemy
   If EnemiesLeft=30
      Gosub respawn
      For Enemy=1 to 30
         If Sprite Visible(Enemy+2)=0
            Show Sprite Enemy+2
         Endif
      next Enemy
      EnemiesLeft=0
   endif
   For Enemy=1 to 10
   	For Enemy2=1 to 3
   		If Sprite Visible(Enemy+2)=0
   			EnemyAttack(Enemy,Enemy2)=0
   			If Enemy2<3
   				EnemyAttack(Enemy,Enemy2+1)=1
   			endif
   		endif
   	next enemy2
   next enemy
   For Enemy=1 to 10
   	For Enemy2=1 to 3
   		If EnemyAttack(Enemy,Enemy2)=1
   			Sprite Enemy+90,EnemyPositionX(Enemy,Enemy2)+20,EnemyPositionY(Enemy2),6
   		endif
   	next enemy2
   next enemy
   For Enemy=1 to 10
   	EnemyBulletFire(Enemy)=EnemyBulletFire(Enemy)-1
   next enemy
   For Enemy=1 to 10
   	If EnemyBulletFire(Enemy)=0
   		Show Sprite Enemy+90
   	endif
   	If EnemyBulletFire(Enemy)=0
   		EnemyBulletFire(Enemy)= Rem set to random time to wait
   	endif
   next enemy
   For Enemy=1 to 10
		For Enemy2=1 to 3
			If EnemyAttack(Enemy,Enemy2)=1
				EnemyBulletY(Enemy)=EnemyPositionY(Enemy2)+25
			endif
		next enemy2
	next enemy
	For Enemy=1 to 10
		For Enemy2=1 to 3
			If EnemyAttack(Enemy,Enemy2)=1
				EnemyBulletX(Enemy)=EnemyPositionX(Enemy,Enemy2)+21
			endif
		next enemy2
	next enemy
   Rem our CLS equivalent
   fill memory mem_loc, 0, 2560000

   for s=0 to starquantity

      sx# = stars(s).x

      Rem works out where in memory to plot our dot!
      mem_y = int(stars(s).y)*(800*4)
      mem_x = (int(sx#)*4)
      mem_location = mem_x + mem_y

		Rem plots
      if mem_location > 1 and mem_location < 2560000
         write memblock dword 1, mem_location, stars(s).color
      endif

		Rem moves the star
      sx# = sx# - stars(s).speed
      if sx# < 0 then sx# = 800
      stars(s).x = sx#

   next s

	Rem This copies the pixel data from memory to the screen
   lock pixels
   copy memory get pixels pointer(), mem_loc, 2560000
   unlock pixels
   Rem speed up music
   Set Sound Speed 1,SoundSpeed
   text 10,10,"Score: "+Str$(Score)
   Rem refresh screen
   Sync
Loop

respawn:
Rem Draw Blue Enemies
For Enemy=1 to 10
	Sprite Enemy+2,Enemy*67,100,2
Next Enemy

Rem Draw Green Enemies
For Enemy=1 to 10
	Sprite Enemy+12,Enemy*67,200,3
Next Enemy

Rem Draw Purple Enemies
For Enemy=1 to 10
	Sprite Enemy+22,Enemy*67,300,4
Next Enemy

EnemyPositionY(1)=100
EnemyPositionY(2)=200
EnemyPositionY(3)=300
XMove=XMove+1
YMove=YMove+0.5
SoundSpeed=35000
Return

Thanx

Back to top

Profile PM Email Website

Lampton Worm

22

Years of Service

User Offline

Joined: 4th Sep 2002

Location: United Kingdom

Posted: 28th May 2004 14:12 Edited at: 28th May 2004 14:13

Hi,

IanM uploaded a snippet to the Codebase for doing count down timers, it may help you out -

http://www.thegamecreators.com/?m=codebase_view&i=c6125a943ea8979ee926dddfe2122168

If not, let me know, good luck!
Cheers.

Back to top

Profile PM Website

GameMaker Jason

21

Years of Service

User Offline

Joined: 22nd Nov 2003

Location: UK

Posted: 29th May 2004 12:10

i think i understnad how it work but im unshore of who i would implimate this in my game so that there is 10 seperate counter that both have a random value so there is no pattern in the shooting of the alien.

Back to top

Profile PM Email Website

Lampton Worm

22

Years of Service

User Offline

Joined: 4th Sep 2002

Location: United Kingdom

Posted: 1st Jun 2004 13:40

Hi,

You could do something like this...(pseudo)

1. Pick a random alien
2. Pick a random number (used for "alien fire" probability)
3. If random alien isn't firing and random number is a certain value, make that alien fire

e.g.

alien_number=rnd(max_aliens)
alien_prob=rnd(10)
if alien_data(alien_number).state=not_firing and alien_prob=1
do_alien_fire
endif

This picks a random alien, and gives them a random chance to fire, if they are not firing already, weighed to 10.

Something along those lines.

I think you'll find it easier if you set up an array for all aliens, and keep a state for them etc.

Hope it helps,
Cheers.

Back to top

Profile PM Website

Lampton Worm

22

Years of Service

User Offline

Joined: 4th Sep 2002

Location: United Kingdom

Posted: 9th Jun 2004 20:30