enemy AI - GameCreators Forum

Author

Message

ChozoMufin

20

Years of Service

User Offline

Joined: 19th Apr 2005

Location: Columbus, OH

Posted: 5th May 2005 11:30

Link

i have an enemy AI system that works well, but has a few problems. like when his misile gets within a certain range it will home, but then if it gets behind me it will turn aroudn and come back. i dont want it to do taht last part. is there some way that once it's past me it cant home anymore?

enemy AI:

+ Code Snippet


REM enemy ai
pX#=camera position x()
pY#=camera position y()	
pZ#=camera position z()	
tX#=object position x(26)
tY#=object position y(26)	
tZ#=object position z(26)	
oldyang#= object angle y(26)

pdist=sqrt((tx#-px#)^2 + (ty#-py#)^2 + (tz#-pz#)^2)
if pdist<1500 and enemybulletlife = 0
	position object 31, tx#, ty#, tz#
	point object 26, px#, py#, pz#
	xrotate object 26, 0
	zrotate object 26, 0
	yrotate object 26, wrapvalue(object angle y(26)+180)
	point object 31, px#, py#, pz#
	enemybulletlife = 100
else	
	yrotate object 26, oldyang#
	move object 26, -5
	tx# = object position x(26)
	tz# = object position z(26)
	position object 26, tx#, get ground height(1, tx#, tz#), tz#
	if object position z(26)<100 
		yrotate object 26, 180
	endif

	 if object position z(26)>9900
		yrotate object 26, 360
	endif
endif

if enemybulletlife > 0 then gosub enemyshootmisile
if enmExplode > 0 then gosub explodetankmisile

enemy shootmisile subroutine:

enemyshootmisile:
	enmX#=object position x(31)
	enmY#=object position y(31)	
	enmZ#=object position z(31)

inc enpn
	if enpn=321 then enpn=310
	Scale object enPn,100,100,100
	Position object enPn,enmX#,enmY#,enmZ#
	Show object enPn
	yrotate object enpn, WrapValue(359-Explode*37)
	for x = 1 to 10
		scale object int((Wrapvalue((enPn-9+x)*36))/36)+110,100+x*25,100+x*25,100+x*25
	set cursor 10,10
	next x

Dec enemyBulletLife
	move object 31, 50

point object enPn,X#,Y#,Z#
	
	REM updated position variables
	enmX#=object position x(31)
	enmY#=object position y(31)	
	enmZ#=object position z(31)	
	pX#=camera position x()
	pY#=camera position y()	
	pZ#=camera position z()	
	
	if enmy#<get ground height(1,enmx#,enmz#) then enemybulletlife = 0

entdist=sqrt((px#-enmx#)^2 + (py#-enmy#)^2 + (pz#-enmz#)^2)
	if entdist <20
		enemybulletlife = 0  
		
		stop music 1
		show object 5
		load 3dsound "explode3.wav", 1
		play sound 1
		wait 2000
		play music 1
		position camera 5000, 1000, 5000
		rotate camera 0, 0, 0
		play sound 6
		misiles=10
		fx#=600
		enemyscore = enemyscore+1
	endif
	
	if entdist <500 and entdist > 250 then point object 31, px#, py#, pz#
	if entdist < 500 
		set cursor 312, 231
		ink rgb(500,0,0),rgb(0,0,0)
		print "warning"	
	endif

if enemybulletlife = 0
		hide object 31
		for x=310 to 320
			hide object x
		next x
		enmExplode = 20
	endif
return

+ Code Snippet

enemyshootmisile:
	enmX#=object position x(31)
	enmY#=object position y(31)	
	enmZ#=object position z(31)	

	inc enpn
	if enpn=321 then enpn=310
	Scale object enPn,100,100,100
	Position object enPn,enmX#,enmY#,enmZ#
	Show object enPn
	yrotate object enpn, WrapValue(359-Explode*37)
	for x = 1 to 10
		scale object int((Wrapvalue((enPn-9+x)*36))/36)+110,100+x*25,100+x*25,100+x*25
	set cursor 10,10
	next x

	Dec enemyBulletLife
	move object 31, 50

	point object enPn,X#,Y#,Z#
	
	REM updated position variables
	enmX#=object position x(31)
	enmY#=object position y(31)	
	enmZ#=object position z(31)	
	pX#=camera position x()
	pY#=camera position y()	
	pZ#=camera position z()	
	
	if enmy#<get ground height(1,enmx#,enmz#) then enemybulletlife = 0

	entdist=sqrt((px#-enmx#)^2 + (py#-enmy#)^2 + (pz#-enmz#)^2)
	if entdist <20
		enemybulletlife = 0  
		
		stop music 1
		show object 5
		load 3dsound "explode3.wav", 1
		play sound 1
		wait 2000
		play music 1
		position camera 5000, 1000, 5000
		rotate camera 0, 0, 0
		play sound 6
		misiles=10
		fx#=600
		enemyscore = enemyscore+1
	endif
	
	if entdist <500 and entdist > 250 then point object 31, px#, py#, pz#
	if entdist < 500 
		set cursor 312, 231
		ink rgb(500,0,0),rgb(0,0,0)
		print "warning"	
	endif

	if enemybulletlife = 0
		hide object 31
		for x=310 to 320
			hide object x
		next x
		enmExplode = 20
	endif
return

Back to top

Profile PM Email Website

Link102

20

Years of Service

User Offline

Joined: 1st Dec 2004

Location: On your head, weeeeee!

Posted: 5th May 2005 21:51 Edited at: 5th May 2005 21:52

Link

give the rocket its own xyz coordinate (newxvalue etc.) then if the target's z is lower than zero, die or somthn
that's what I'dd do

please reply

Back to top

Profile PM

Sven B

20

Years of Service

User Offline

Joined: 5th Jan 2005

Location: Belgium

Posted: 6th May 2005 23:40

Link

What do you think of this code:

sync on

`make "bullet"
make object box 1,1,1,10
position object 1,0,0,0

`make target
make object cube 2,5
position object 2,0,0,100

do

`CALL FUNCTION
	locked(1,2,0.1)

`press left/right to strafe the target left/right
	if leftkey()=1 then position object 2,object position x(2) - 2,0,100
	if rightkey()=1 then position object 2,object position x(2) + 2,0,100

sync
loop

`in a function
function locked(id,target,turningspeed#)

`first of all: get -id- data
	posx#=object position x(id)
	posz#=object position z(id)
	angy#=object angle y(id)

`get -target- data
	targetx#=object position x(target)
	targetz#=object position z(target)

`calculate the angle between -id- and -target-
	angle# = wrapvalue( angy# - atanfull((targetx# - posx#) , (targetz# - posz#)) )

`if angle <180 / >180 then turn left/right
	if angle# >=180
		if angle#<359.0 then yrotate object 1, wrapvalue( angy# + turningspeed# )
	else
		if angle#>1.0 then yrotate object 1, wrapvalue( angy# - turningspeed#)
	endif

endfunction

+ Code Snippet

sync on

`make "bullet"
make object box 1,1,1,10
position object 1,0,0,0

`make target
make object cube 2,5
position object 2,0,0,100

do

	`CALL FUNCTION
	locked(1,2,0.1)

	`press left/right to strafe the target left/right
	if leftkey()=1 then position object 2,object position x(2) - 2,0,100
	if rightkey()=1 then position object 2,object position x(2) + 2,0,100

	sync
loop

`in a function
function locked(id,target,turningspeed#)

	`first of all: get -id- data
	posx#=object position x(id)
	posz#=object position z(id)
	angy#=object angle y(id)

	`get -target- data
	targetx#=object position x(target)
	targetz#=object position z(target)

	`calculate the angle between -id- and -target-
	angle# = wrapvalue( angy# - atanfull((targetx# - posx#) , (targetz# - posz#)) )

	`if angle <180 / >180 then turn left/right
	if angle# >=180
		if angle#<359.0 then yrotate object 1, wrapvalue( angy# + turningspeed# )
	else
		if angle#>1.0 then yrotate object 1, wrapvalue( angy# - turningspeed#)
	endif

endfunction

The "id" will turn towards "target" at a given speed ("turningspeed#").

Back to top

Profile PM Email

ChozoMufin

20

Years of Service

User Offline

Joined: 19th Apr 2005

Location: Columbus, OH

Posted: 8th May 2005 11:59 Edited at: 8th May 2005 12:00

Link

that works fine on a 2d plane, but my game is full 3d. i have been tweaking that for several days to conform to my game and still cannot get it to work. what am i doing wrong???

+ Code Snippet

function enemylocked(id,target,turningspeed#)

	posx#=object position x(id)
	posz#=object position z(id)
	posy#=object position y(id)

	angy#=object angle y(id)
	angx#=object angle x(id)

	targetx#=object position x(target)
	targetz#=object position z(target)
	targety#=object position y(target)

	angley# = wrapvalue(angy#-atanfull((targetx#-posx#),(targetz#-posz#)))
	anglex# = wrapvalue(angx#-atanfull((targetz#-posz#),(targety#-posy#)))
	
	if angley# >=180
		if angley#<359.0 then yrotate object 31, wrapvalue(angy#+turningspeed#)
	else
		if angley#>1.0 then yrotate object 31, wrapvalue(angy#-turningspeed#)
	endif
	
	if anglex# <=180
		if anglex#>1.0 then xrotate object 31, wrapvalue(angx#+turningspeed#)
	else
		if anglex#<359.0 then xrotate object 31, wrapvalue(angx#-turningspeed#)
	endif


endfunction

oh yeah, and dont worry about why i switched the if endif statement around for x rotation. that was just something i tried and didnt work. its still exactly the same thing, just flipped around for no reason and i was too lazy to re-flip.

Who can withstand the awesome power of the almighty Lord of the Butmunch?

Back to top

Profile PM Email Website

waffle

22

Years of Service

User Offline

Joined: 9th Sep 2002

Location: Western USA

Posted: 8th May 2005 17:41

Link

I recommend dropping the angle X refrence, just for simplicity.

first save old data
angy#=object angle y(id)
angx#=object angle x(id)

Then, simply cheat and use the function
point object ID,targetx#,targety#,targetz#

followed by
tanglex#=object angle x(id)
tangley#=object angle y(id)
tanglez#=object angle z(id)

Then, use the code above for turning speed
and then

rotate object ID,tanglex#,newangley#,tanglez#

this should work ...

but, if you want fancier code,
you could simply do a test on how much, and in which direction,
the anlges change and limit them to some number ...

Back to top

Profile PM Email Website

Sven B

20

Years of Service

User Offline

Joined: 5th Jan 2005

Location: Belgium

Posted: 8th May 2005 21:04

Link

Sorry guys, i found a bug in my function.
This is the updated 1:

sync on

`make "bullet"
make object box 1,1,1,10
position object 1,0,0,0

`make target
make object cube 2,5
position object 2,0,0,100

do

`CALL FUNCTION
	locked(1,2,0.1)

`press left/right to strafe the target left/right
	if leftkey()=1 then position object 2,object position x(2) - 2,object position y(2),100
	if rightkey()=1 then position object 2,object position x(2) + 2,object position y(2),100

sync
loop

`in a function
function locked(id,target,turningspeed#)

`first of all: get -id- data
	posx#=object position x(id)
	posz#=object position z(id)
	angy#=object angle y(id)

`get -target- data
	targetx#=object position x(target)
	targetz#=object position z(target)

`calculate the angle between -id- and -target-
	yangle# = wrapvalue( angy# - atanfull((targetx# - posx#) , (targetz# - posz#)) )

`if angle <180 / >180 then turn left/right
	if yangle# >=180
		if yangle#<359.0 then yrotate object id, wrapvalue( angy# + turningspeed# )
	else
		if yangle#>1.0 then yrotate object id, wrapvalue( angy# - turningspeed# )
	endif

endfunction

+ Code Snippet

sync on

`make "bullet"
make object box 1,1,1,10
position object 1,0,0,0

`make target
make object cube 2,5
position object 2,0,0,100

do

	`CALL FUNCTION
	locked(1,2,0.1)

	`press left/right to strafe the target left/right
	if leftkey()=1 then position object 2,object position x(2) - 2,object position y(2),100
	if rightkey()=1 then position object 2,object position x(2) + 2,object position y(2),100

	sync
loop

`in a function
function locked(id,target,turningspeed#)

	`first of all: get -id- data
	posx#=object position x(id)
	posz#=object position z(id)
	angy#=object angle y(id)

	`get -target- data
	targetx#=object position x(target)
	targetz#=object position z(target)

	`calculate the angle between -id- and -target-
	yangle# = wrapvalue( angy# - atanfull((targetx# - posx#) , (targetz# - posz#)) )

	`if angle <180 / >180 then turn left/right
	if yangle# >=180
		if yangle#<359.0 then yrotate object id, wrapvalue( angy# + turningspeed# )
	else
		if yangle#>1.0 then yrotate object id, wrapvalue( angy# - turningspeed# )
	endif

endfunction

Back to top

Profile PM Email

ChozoMufin

20

Years of Service

User Offline

Joined: 19th Apr 2005

Location: Columbus, OH

Posted: 9th May 2005 11:13 Edited at: 9th May 2005 11:14

Link

here's my problem. i want it to track on 2 dimensions, up and sideways (xrotation and yrotation). when the enemy shoots at me, it will turn too high up or too far down and miss me, even if i go slowly and straight at him. i already gave you my code. please tell me how to do what i want to do and what i did wrong.

Who can withstand the awesome power of the almighty Lord of the Butmunch?

Back to top

Profile PM Email Website

Sven B

20

Years of Service

User Offline

Joined: 5th Jan 2005

Location: Belgium

Posted: 9th May 2005 19:06

Link

The angle values don't match. If you use x angles you have to rewrite your code instead of copy it.

Suggestion: draw it on a piece of paper! It works with me...

Back to top

Profile PM Email

ChozoMufin

20

Years of Service

User Offline

Joined: 19th Apr 2005

Location: Columbus, OH

Posted: 10th May 2005 07:41

Link

ok. but ive tried every concievable conbination of x, z, and y values for the atanfull part. none of them work.

Who can withstand the awesome power of the almighty Lord of the Butmunch?

Back to top

Profile PM Email Website

Sven B

20

Years of Service

User Offline

Joined: 5th Jan 2005

Location: Belgium

Posted: 11th May 2005 03:18

Link

I did it!!! A full 3D lock on function!

Here it is:

sync on

`make "bullet"
make object box 1,1,1,10 : point object 1,0,0,100
position object 1,0,0,0

`make target
make object cube 2,5
position object 2,0,0,100

do

`CALL FUNCTION
	locked(1,2,0.1)

`press left/right to strafe the target left/right
	if leftkey()=1 then position object 2,object position x(2) - 2,object position y(2),object position z(2)
	if rightkey()=1 then position object 2,object position x(2) + 2,object position y(2),object position z(2)
	if upkey()=1 then position object 2,object position x(2),object position y(2) + 2,object position z(2)
	if downkey()=1 then position object 2,object position x(2),object position y(2) - 2,object position z(2)

sync
loop

`in a function
function locked(id,target,turningspeed#)

`first of all: get -id- data
	posx#=object position x(id)
	posy#=object position y(id)
	posz#=object position z(id)
	angy#=object angle y(id)
	angx#=object angle x(id)

`get -target- data
	targetx#=object position x(target)
	targety#=object position y(target)
	targetz#=object position z(target)

`calculate the angle between -id- and -target-
	yangle# = wrapvalue( angy# - atanfull(targetx# - posx# , targetz# - posz#) )
	xangle# = wrapvalue( 90 + angx# - atanfull(targetz# - posz# , targety# - posy#) )

`if angle <180 / >180 then turn left/right or up/down
	if yangle# >=180
		if yangle#<359.0 then yrotate object id, wrapvalue( angy# + turningspeed# )
	else
		if yangle#>1.0 then yrotate object id, wrapvalue( angy# - turningspeed# )
	endif

if xangle# >=180
		if xangle#<359.0 then xrotate object id, wrapvalue( angx# + turningspeed# )
	else
		if xangle#>1.0 then xrotate object id, wrapvalue( angx# - turningspeed# )
	endif

endfunction

+ Code Snippet

sync on

`make "bullet"
make object box 1,1,1,10 : point object 1,0,0,100
position object 1,0,0,0

`make target
make object cube 2,5
position object 2,0,0,100

do

	`CALL FUNCTION
	locked(1,2,0.1)

	`press left/right to strafe the target left/right
	if leftkey()=1 then position object 2,object position x(2) - 2,object position y(2),object position z(2)
	if rightkey()=1 then position object 2,object position x(2) + 2,object position y(2),object position z(2)
	if upkey()=1 then position object 2,object position x(2),object position y(2) + 2,object position z(2)
	if downkey()=1 then position object 2,object position x(2),object position y(2) - 2,object position z(2)

	sync
loop

`in a function
function locked(id,target,turningspeed#)

	`first of all: get -id- data
	posx#=object position x(id)
	posy#=object position y(id)
	posz#=object position z(id)
	angy#=object angle y(id)
	angx#=object angle x(id)

	`get -target- data
	targetx#=object position x(target)
	targety#=object position y(target)
	targetz#=object position z(target)

	`calculate the angle between -id- and -target-
	yangle# = wrapvalue( angy# - atanfull(targetx# - posx# , targetz# - posz#) )
	xangle# = wrapvalue( 90 + angx# - atanfull(targetz# - posz# , targety# - posy#) )

	`if angle <180 / >180 then turn left/right or up/down
	if yangle# >=180
		if yangle#<359.0 then yrotate object id, wrapvalue( angy# + turningspeed# )
	else
		if yangle#>1.0 then yrotate object id, wrapvalue( angy# - turningspeed# )
	endif

	if xangle# >=180
		if xangle#<359.0 then xrotate object id, wrapvalue( angx# + turningspeed# )
	else
		if xangle#>1.0 then xrotate object id, wrapvalue( angx# - turningspeed# )
	endif

endfunction

I found it when i was printing the x-angle and the y-angle on the screen.

Back to top

Profile PM Email

ChozoMufin

20

Years of Service

User Offline

Joined: 19th Apr 2005

Location: Columbus, OH

Posted: 17th May 2005 03:20

Link

HALELUJAH!!!!!!!!!!!!!!!!!!!!!!!!!!! ur a genious!

dude, you rock!!! thank you sooooooo much. this has been the major stopping block in the creation of my game, and now it's gone! now lets see how long it takes before another one gets in my way,... anyways, thank you so much

!!!!

Who can withstand the awesome power of the almighty Lord of the Butmunch?

Back to top

Profile PM Email Website

Sven B

20

Years of Service

User Offline

Joined: 5th Jan 2005

Location: Belgium

Posted: 17th May 2005 03:38

Link

Man, i have some bad news for you: It doesn't work.

When you pitch and turn, you are rotating around your z-axis. Wich means it won't work...

Back to top

Profile PM Email

ChozoMufin

20

Years of Service

User Offline

Joined: 19th Apr 2005

Location: Columbus, OH

Posted: 17th May 2005 05:07 Edited at: 17th May 2005 05:37

Link

well, i guess i found the new stumbling block. that works great in that one bit of code in itself, but when i use it in my program it turns way the heck the wrong way. i haven't a clue why it doesnt work. this is my only hint: in the bit of code you gave me, i added the move object command. but when i do, although it will point at the target, it will not move in the direction of the target.

Who can withstand the awesome power of the almighty Lord of the Butmunch?

Back to top

Profile PM Email Website

ChozoMufin

20

Years of Service

User Offline

Joined: 19th Apr 2005

Location: Columbus, OH

Posted: 17th May 2005 05:38 Edited at: 17th May 2005 05:39

Link

it worked fine in your code, though. hmmmmmm, i wonder,... could you not just add the same algorithm for the angle but for the z axis? I'll try that.

Who can withstand the awesome power of the almighty Lord of the Butmunch?

Back to top

Profile PM Email Website

ChozoMufin

20

Years of Service

User Offline

Joined: 19th Apr 2005

Location: Columbus, OH

Posted: 17th May 2005 05:45

Link

alas! it wont work. oh well. i was thinking of changing the game to a helicopter game, and helicopters can't lock on to stuff with their misiles. but still, if someone can find a way, PLEASE TELL ME!!!

Who can withstand the awesome power of the almighty Lord of the Butmunch?

Back to top

Profile PM Email Website

Sven B

20

Years of Service

User Offline

Joined: 5th Jan 2005

Location: Belgium

Posted: 17th May 2005 20:39

Link

Maybe you can make a dummy object wich points at the target.

+ Code Snippet

position object dummy,object position x(bullet), object position y(bullet), object position z(bullet)
point object dummy,targetx#,targety#,targetz#

bulletangx# = curveangle( object angle x(dummy), object angle x(bullet), 50)
bulletangy# = curveangle( object angle y(dummy), object angle y(bullet), 50)
bulletangz# = curveangle( object angle z(dummy), object angle z(bullet), 50)

´update bullet
rotate object bullet, bulletangx#, bulletangy#, bulletangz#
move object bullet, bulletspeed#

I didn't test it, but it might even work!!!

Don't give up your fps!

Back to top

Profile PM Email

Sven B

20

Years of Service

User Offline

Joined: 5th Jan 2005

Location: Belgium

Posted: 17th May 2005 20:45

Link

Oh, before i forget. you can also ajust it a little by using:

+ Code Snippet

if bulletangx# < wrapvalue(object angle x(dummy) - 1.0)
  if bulletangx# > wrapvalue(object angle x(dummy) - 180)
    xrotate object bullet, wrapvalue(object angle x(bullet) + turningspeed#)
  endif
endif

if bulletangx# > wrapvalue(object angle x(dummy) + 1.0)
  if bulletangx# < wrapvalue(object angle x(dummy) - 180)
    xrotate object bullet, wrapvalue(object angle x(bullet) - turningspeed#)
  endif
endif
´--- Do this for y and z as well ---

instead of:

+ Code Snippet

bulletangx# = curveangle( object angle x(dummy), object angle x(bullet), 50)
bulletangy# = curveangle( object angle y(dummy), object angle y(bullet), 50)
bulletangz# = curveangle( object angle z(dummy), object angle z(bullet), 50)

´update bullet
rotate object bullet, bulletangx#, bulletangy#, bulletangz#

Back to top

Profile PM Email

ChozoMufin

20

Years of Service

User Offline

Joined: 19th Apr 2005

Location: Columbus, OH

Posted: 24th May 2005 06:57

Link

I will try that.

Your Head A-Splode

Back to top

Profile PM Email Website

Sorry your browser is not supported!

DarkBASIC Discussion / enemy AI