Need help with my Tank Game

[Dragoon]

I having trouble trying to get my tank to move while shooting.

code:

setscreen ("graphics:800;500") setscreen ("nocursor") var Bullet: int var Game : int var Tank : int var x : int := 0 var reply : string (1) var Tank2 : int Game := Pic.FileNew ("Game2.bmp") %Locates the picture Pic.Draw (Game, 0, 0, 2) %Draws the picture Tank := Pic.FileNew ("Tank.bmp") %Locates the picture Pic.Draw (Tank, 320, -230, 2) %Draws the picture Bullet := Pic.FileNew ("bullet.bmp") %Locates the picture Tank2 := Pic.FileNew ("Tank2.bmp") %Locates the picture Pic.Draw (Tank2, 240, 220, 2) %Draws the picture loop     getch (reply)     if reply = "d" then     Pic.Draw (Game, 0, 0, 2)     Pic.Draw (Tank, 320 + x, -230, 2) %Draws the picture     Pic.Draw (Tank2, 240, 220, 2) %Draws the picture     x := x + 12     end if     if reply = "a" then     Pic.Draw (Game, 0, 0, 2)     Pic.Draw (Tank, 320 + x, -230, 2) %Draws the picture     Pic.Draw (Tank2, 240, 220, 2) %Draws the picture     x:= x - 12     end if     if reply = "x" then     for i: 1..400     Pic.Draw (Bullet, 80 + x, -170 + i, 2) %Draws the picture     end for     end if     if x = 0 then     Pic.Draw (Game, 0, 0, 2)     Pic.Draw (Tank, 320 + x, -230, 2) %Draws the picture     end if end loop By the way a is to move left, d is to move right and x is to fire.

[Asok]

rule of thumb. ALWAYS upload your external bitmaps.

just zip them up and attach them so we can actually run this.

[Tony]

if might help if you'd use Input.KeyDown instead... read tutorial... everybody who knows how to use that recomments it over getch...

now, you should make a separate procedure for the bullet that will move it along its trajectory. Then set a flag variable in the main loop so that the procedure keeps on getting called to move the bullet while its on screen. This way it moves bullet 1 spot, then returns to tank controls to allow you to move it as well..

are you with me so far?

[Dragoon]

How would i use Input.KeyRight in my code? Can you give me an example please.

[Dragoon]

Okay , i got everything to work except for the Bullet, i made a procedure and now how do i have it so the bullet moves while the tank moves too?

[Tony]

structure it like this:

procedure moveBullet
bulletX += movementX
bulletY += movementY
%maye some other stuff like check if it hit something or what not
%reset bulletFlag back to flase once bullet is done moving
end moveBullet

%main loop
loop
input.ketdown stuff
if chars('f') then
%or whatever button you want to fire with
bulletFlag = true
end if

if bulletFlag then
moveBullet
end if

move tank here
end loop

/\Something like that above

[Dragoon]

Below is the code i have right now.

[Dragoon]

Okay, iam having trouble understanding what you just put, what do i have to do with the bullety and x stuff in the procedure? Also do i have my Draw Bullet in the right spot?

code:

setscreen ("graphics:800;500") setscreen ("nocursor") var Bullet : int var Game : int var Tank : int var x : int := 0 var reply : string (1) var Tank2 : int var bulletX : int var movementX : int var movementY : int var bulletY : int var bulletflag : boolean := true Game := Pic.FileNew ("Game2.bmp") %Locates the picture Pic.Draw (Game, 0, 0, 2) %Draws the picture Tank := Pic.FileNew ("Tank.bmp") %Locates the picture Pic.Draw (Tank, 320, -230, 2) %Draws the picture Bullet := Pic.FileNew ("bullet.bmp") %Locates the picture Tank2 := Pic.FileNew ("Tank2.bmp") %Locates the picture Pic.Draw (Tank2, 240, 220, 2) %Draws the picture var chars : array char of boolean procedure moveBullet     bulletX += movementX     bulletY += movementY     Pic.Draw (Bullet, 80 + x, -170, 2)  %Draws the picture     bulletflag := false end moveBullet loop     Input.KeyDown (chars)     if chars (KEY_ENTER) then         bulletflag := true     end if     if bulletflag then         moveBullet     end if     if chars (KEY_RIGHT_ARROW) then         Pic.Draw (Game, 0, 0, 2)         Pic.Draw (Tank, 320 + x, -230, 2) %Draws the picture         Pic.Draw (Tank2, 240, 220, 2) %Draws the picture         x := x + 12     end if     if chars (KEY_LEFT_ARROW) then         Pic.Draw (Game, 0, 0, 2)         Pic.Draw (Tank, 320 + x, -230, 2) %Draws the picture         Pic.Draw (Tank2, 240, 220, 2) %Draws the picture         x := x - 12     end if end loop

[Tony]

your procedure should look like this:

code:

procedure moveBullet     bulletX += movementX     bulletY += movementY     Pic.Draw (Bullet, bulletX, bulletY, 2)  %Draws the picture if bulletY>maxy then     bulletflag := false end if end moveBullet

so the flag is set to false, only when the bullet goes over the top of the screen.

I think your movement variables should be procedure parameters, because otherwise if you turn your tank around, the bullet will turn too.

[Dragoon]

Do i have to declare the BulletX, BulletY, MovementX, MovementY anything?

[Tony]

yes

[Dragoon]

What would i delcare them? Sorry for asking too many questions.

[Tony]

bulletX/Y is a location of the bullet
movementX/Y is vector components of bullet's trajectory. You add them to bulletX/Y to move it.

tankX/Y is location of your tank. When bullet if first fired, bulletX/Y = tankX/Y...

tankMovementX/Y also vector components, store tank movement direction. When bullet is first fired, movementX/Y = tankMovementX/Y

you can declear them as integers, but if you want more accurate numbers, use real instead and just round for drawing.

[Dragoon]

Okay, i understand it now, but whenever i start my program the bullet fires. This is what i have.

code:

setscreen ("graphics:800;500") setscreen ("nocursor") var Bullet : int var Game : int var Tank : int var x : int := 0 var y : int := 1 var reply : string (1) var Tank2 : int var bulletX : int := 80 var movementX : int := 0 var movementY : int := 1 var bulletY : int := -170 var bulletflag : boolean := true Game := Pic.FileNew ("Game2.bmp") %Locates the picture Pic.Draw (Game, 0, 0, 2) %Draws the picture Tank := Pic.FileNew ("Tank.bmp") %Locates the picture Pic.Draw (Tank, 320, -230, 2) %Draws the picture Bullet := Pic.FileNew ("bullet.bmp") %Locates the picture Tank2 := Pic.FileNew ("Tank2.bmp") %Locates the picture Pic.Draw (Tank2, 240, 220, 2) %Draws the picture var chars : array char of boolean procedure moveBullet     bulletX += movementX     bulletY += movementY     Pic.Draw (Bullet, bulletX, bulletY, 2)  %Draws the picture if bulletY>maxy then bulletflag := false end if end moveBullet loop     Input.KeyDown (chars)     if chars (KEY_ENTER) then         bulletflag := true     end if     if bulletflag = true then     moveBullet     end if     if chars (KEY_RIGHT_ARROW) then         Pic.Draw (Game, 0, 0, 2)         Pic.Draw (Tank, 320 + x, -230, 2) %Draws the picture         Pic.Draw (Tank2, 240, 220, 2) %Draws the picture         x := x + 12     end if     if chars (KEY_LEFT_ARROW) then         Pic.Draw (Game, 0, 0, 2)         Pic.Draw (Tank, 320 + x, -230, 2) %Draws the picture         Pic.Draw (Tank2, 240, 220, 2) %Draws the picture         x := x - 12     end if         end loop

[Tony]

thats cuz you initialize your bulletFlag variable to true when you declear it. Make it false instead.