How to shoot a gun in a 2d enviroment

Author

Message

Avalanche_ Akshay

19

Years of Service

User Offline

Joined: 27th Jun 2005

Location:

Posted: 16th Aug 2005 14:22

Link

i really must know how to shoot a gun in a 2d enviroment. i know some basic codes but i need to shoot multiple bullets find a way to increases the velocity without decreasing the velocity. If you guys could help it would make it easier. here is what i know about shooting in 2d enviroment. first the bullet has to come to you second the bullet has to move depending on which direction you face.
(this cannot be used with multiple shots)

speed#=2
sync on
do
cls
make the guy move and jump and stuff*
sprite bullet,b#,y#,bullet
inc b#,speed#
make a basic comand so that the person faces the way you want it to. use a variable to do so. if facing#=1 then the person face right if it is 0 the person faces left.*
if facing#=0 then speed#=2
if facing#=1 then speed#=-2
if spacebar()=1
b#=xpos#(players position)
y#=ypos#(players position)
ypos#=y#
endif
now just add gravity and the bullet moves, however if you repetedly press space bar it shall look like a taser*
sync
loop
*not real code

Back to top

Profile PM

Sven B

19

Years of Service

User Offline

Joined: 5th Jan 2005

Location: Belgium

Posted: 16th Aug 2005 14:36 Edited at: 16th Aug 2005 14:38

Link

You will probably need arrays.

like this:

dim bullet_dat(50,3)
`(the 1 is the xval, the 2 is the yval and the 3 is the direction)
currentbullet = 1

do

`only bulletcode here
   if spacekey() = 1 and delay = 0
      delay = 30
      inc currentbullet
      bullet_dat(currentbullet,1) = playerx
      bullet_dat(currentbullet,2) = playery
      bullet_dat(currentbullet,3) = direction
      `(direction: 1 = up, 2 = right, 3 = down and 4 = left)
   endif

`handle bullets
   for bullet = 1 to 50
      if bullet_dat(bullet,1) > 0 and bullet_dat(bullet,1) < screen width()
         if bullet_dat(bullet,2) > 0 and bullet_dat(bullet,2) < screen height()
            select bullet_dat(bullet,3)
               case 1 : bullet_dat(bullet,2) = bullet_dat(bullet,2) - 1 : endcase
               case 2 : bullet_dat(bullet,1) = bullet_dat(bullet,1) + 1 : endcase
               case 3 : bullet_dat(bullet,2) = bullet_dat(bullet,2) + 1 : endcase
               case 4 : bullet_dat(bullet,1) = bullet_dat(bullet,1) - 1 : endcase
            endselect
            sprite bullet,bullet_dat(bullet,1),bullet_dat(bullet,2),b_image
         endif
      endif
   endif

`handle delay
   if delay > 0 then dec delay

sync
loop

+ Code Snippet

dim bullet_dat(50,3)
`(the 1 is the xval, the 2 is the yval and the 3 is the direction)
currentbullet = 1

do

   `only bulletcode here
   if spacekey() = 1 and delay = 0
      delay = 30
      inc currentbullet
      bullet_dat(currentbullet,1) = playerx
      bullet_dat(currentbullet,2) = playery
      bullet_dat(currentbullet,3) = direction
      `(direction: 1 = up, 2 = right, 3 = down and 4 = left)
   endif

   `handle bullets
   for bullet = 1 to 50
      if bullet_dat(bullet,1) > 0 and bullet_dat(bullet,1) < screen width()
         if bullet_dat(bullet,2) > 0 and bullet_dat(bullet,2) < screen height()
            select bullet_dat(bullet,3)
               case 1 : bullet_dat(bullet,2) = bullet_dat(bullet,2) - 1 : endcase
               case 2 : bullet_dat(bullet,1) = bullet_dat(bullet,1) + 1 : endcase
               case 3 : bullet_dat(bullet,2) = bullet_dat(bullet,2) + 1 : endcase
               case 4 : bullet_dat(bullet,1) = bullet_dat(bullet,1) - 1 : endcase
            endselect
            sprite bullet,bullet_dat(bullet,1),bullet_dat(bullet,2),b_image
         endif
      endif
   endif

   `handle delay
   if delay > 0 then dec delay

   sync
loop

*not tested

Immunity and Annihalation makes Immunihalation...

Back to top

Profile PM Email

Avalanche_ Akshay

19

Years of Service

User Offline

Joined: 27th Jun 2005

Location:

Posted: 16th Aug 2005 14:52

Link

thanks for the info but i find your whole code to complectated, i thought that it would be better to clone the bullet(about 50 times!!)

. but i found an easier way which is not tested.
for the sprites number value of recognition which i put as bullet you could instead do this

+ Code Snippet

sprite#=1000
sync on
do
cls
inc sprite#
clone sprite 1000,sprite#
sync
loop

it would still be difficult to control more than one but thanks to your codes i think i shall be able to understand it.

Back to top

Profile PM

Avalanche_ Akshay

19

Years of Service

User Offline

Joined: 27th Jun 2005

Location:

Posted: 16th Aug 2005 14:53

Link

also could u explain your code.

Back to top

Profile PM

Sven B

19

Years of Service

User Offline

Joined: 5th Jan 2005

Location: Belgium

Posted: 16th Aug 2005 22:13 Edited at: 16th Aug 2005 22:16

Link

`first of all create the array to store all bullet data
dim bullet_dat(50,3)
`the 1 is the xval, the 2 is the yval and the 3 is the direction
`this means that bullet_dat(1,1) is the xposition of bullet nr 1
`bullet_dat(5,2) means the yposition of bullet nr 5
`bullet_dat(25,3) means the direction of bullet nr 25

`this variable is going to be used to check wich bullet is at turn.
currentbullet = 0

do

`only bulletcode here
   `if the spacekey is pressed and the delay = 0 then shoot
   `the delay var is used to stop shooting at incredible speed.
   `if currentbullet < 50 (max bullets) the you cannot shoot anymore
   `--> you need to reload.
   if spacekey() = 1 and delay = 0 and currentbullet < 50
      `delay
      delay = 30
      `increase the current bullet
      inc currentbullet
      `make the bullet data match the player data
      bullet_dat(currentbullet,1) = playerx
      bullet_dat(currentbullet,2) = playery
      bullet_dat(currentbullet,3) = direction
      `(direction: 1 = up, 2 = right, 3 = down and 4 = left)
   endif

`handle bullets
   for bullet = 1 to 50
      `if the bullet is in the screen...
      if bullet_dat(bullet,1) > 0 and bullet_dat(bullet,1) < screen width() and bullet_dat(bullet,2) > 0 and bullet_dat(bullet,2) < screen height()
         `then check the direction the bullet is heading
         `(check the arrays for the data)
         `and move the bullets
         select bullet_dat(bullet,3)
            case 1 : bullet_dat(bullet,2) = bullet_dat(bullet,2) - 1 : endcase
            case 2 : bullet_dat(bullet,1) = bullet_dat(bullet,1) + 1 : endcase
            case 3 : bullet_dat(bullet,2) = bullet_dat(bullet,2) + 1 : endcase
            case 4 : bullet_dat(bullet,1) = bullet_dat(bullet,1) - 1 : endcase
         endselect
         sprite bullet,bullet_dat(bullet,1),bullet_dat(bullet,2),b_image
      else
         `if the bullet is out of the screen then reset it's position
         bullet_dat(bullet,1) = -5
         bullet_dat(bullet,2) = -5
         hide sprite bullet
      endif
   endif

`handle delay (if 0, you can shoot again)
   if delay > 0 then dec delay

sync
loop

+ Code Snippet

`first of all create the array to store all bullet data
dim bullet_dat(50,3)
`the 1 is the xval, the 2 is the yval and the 3 is the direction
`this means that bullet_dat(1,1) is the xposition of bullet nr 1
`bullet_dat(5,2) means the yposition of bullet nr 5
`bullet_dat(25,3) means the direction of bullet nr 25

`this variable is going to be used to check wich bullet is at turn.
currentbullet = 0

do

   `only bulletcode here
   `if the spacekey is pressed and the delay = 0 then shoot
   `the delay var is used to stop shooting at incredible speed.
   `if currentbullet < 50 (max bullets) the you cannot shoot anymore
   `--> you need to reload.
   if spacekey() = 1 and delay = 0 and currentbullet < 50
      `delay
      delay = 30
      `increase the current bullet
      inc currentbullet
      `make the bullet data match the player data
      bullet_dat(currentbullet,1) = playerx
      bullet_dat(currentbullet,2) = playery
      bullet_dat(currentbullet,3) = direction
      `(direction: 1 = up, 2 = right, 3 = down and 4 = left)
   endif

   `handle bullets
   for bullet = 1 to 50
      `if the bullet is in the screen...
      if bullet_dat(bullet,1) > 0 and bullet_dat(bullet,1) < screen width() and bullet_dat(bullet,2) > 0 and bullet_dat(bullet,2) < screen height()
         `then check the direction the bullet is heading
         `(check the arrays for the data)
         `and move the bullets
         select bullet_dat(bullet,3)
            case 1 : bullet_dat(bullet,2) = bullet_dat(bullet,2) - 1 : endcase
            case 2 : bullet_dat(bullet,1) = bullet_dat(bullet,1) + 1 : endcase
            case 3 : bullet_dat(bullet,2) = bullet_dat(bullet,2) + 1 : endcase
            case 4 : bullet_dat(bullet,1) = bullet_dat(bullet,1) - 1 : endcase
         endselect
         sprite bullet,bullet_dat(bullet,1),bullet_dat(bullet,2),b_image
      else
         `if the bullet is out of the screen then reset it's position
         bullet_dat(bullet,1) = -5
         bullet_dat(bullet,2) = -5
         hide sprite bullet
      endif
   endif

   `handle delay (if 0, you can shoot again)
   if delay > 0 then dec delay

   sync
loop

I added a couple of things than in the previous code.
I cannot guarantee that the code will work, since I didn't test it. If something isn't right, please tell me.
The code is fully commented

Immunity and Annihalation makes Immunihalation...

Back to top

Profile PM Email

Avalanche_ Akshay

19

Years of Service

User Offline

Joined: 27th Jun 2005

Location:

Posted: 17th Aug 2005 00:33

Link

thanks
i think i understand now, never used case comand before
how do you state infinity?
without causing a major system shutdown.
i only know basics

Back to top

Profile PM

Sven B

19

Years of Service

User Offline

Joined: 5th Jan 2005

Location: Belgium

Posted: 17th Aug 2005 21:35

Link

A computer will never know what to do with infinity. Infinity isn't even a number. So you won't be able to state infinity.

Immunity and Annihalation makes Immunihalation...

Back to top

Profile PM Email

Sorry your browser is not supported!

Newcomers DBPro Corner / How to shoot a gun in a 2d enviroment