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How To Handle More than One Object

Started by kevin, January 02, 2006, 06:55:41 AM

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kevin

January 02, 2006, 06:55:41 AM Last Edit: October 16, 2012, 12:22:41 AM by kevin
Sorry This tutorial is code only for now.




PlayBASIC Code: [Select]
; Make a ball image
  Size=100
  CreateImage 1,Size,Size
  RenderPhongImage 1,Size/2,Size/2,$ffff8f,size*0.9,2.0


; define a ball type
   Type tBall
         Status
         Xpos,Ypos
         SpeedX,SpeedY
     Image
     LifeTimer
     FlashToggle
   EndType

; create an array to house our list of balls
 dim Balls(1) as tBall



; Main Loop

Do
   Cls rgb(20,30,40)
  Print "press space to create ball"
     

  UpdateBalls()
  
   ; Check for space key
  If SPacekey() and KeyPress=false

  ; Calc a random starting position for this ball
     Xpos=Rnd(GetScreenWIdth())
     Ypos=Rnd(GetScreenHeight())
   
  ; Create (init) a ball at this position and give it a random speed    
     CreateBall(Xpos,Ypos,NewSpeed(5),NewSpeed(5))

     KeyPress=True

  else
     If SPacekey()=false then KeyPress=false
  endif
   
   Sync   
loop



; this function finds a random speed for a ball axis. 
Function NewSpeed(Max)
   Repeat
  Speed=RndRange(-max,max)   
   Until   Speed<>0
EndFunction Speed



Function UpdateBalls()
   ; run through all   
  ScreenWidth=GetSCreenWidth()
  ScreenHeight=GetSCreenHeight()
   
  CurrentTime=Timer()
   
  For lp=1 to GetArrayelements(Balls().tball,1)
     if Balls(lp).Status=True

    ThisImage=Balls(lp).Image
    ImageWidth   =GetImageWidth(ThisImage)/2
    ImageHeight   =GetImageHeight(ThisImage)/2
    
     ; Move the ball on the X axis
    NewXpos=Balls(lp).Xpos+Balls(lp).SpeedX

     ; Check for Left Edge redbound
    If NewXpos<=ImageWidth 
       NewXpos=ImageWidth   
       Balls(lp).SpeedX=Balls(lp).SpeedX*-1
    endif
     
     ; check for right edge rebound
    If NewXpos=>(ScreenWidth-ImageWidth) 
       NewXpos=ScreenWidth-ImageWidth   
       Balls(lp).SpeedX=Balls(lp).SpeedX*-1
    endif
   
     ; MOve the ball along the y axis
    NewYpos=Balls(lp).Ypos+Balls(lp).SpeedY
     ; Check for Left Edge redbound
    If NewYpos<ImageHeight 
       NewYpos=ImageHeight
       Balls(lp).SpeedY=-Balls(lp).SpeedY
    endif
     
     ; check for right edge rebound
    If NewYpos>(ScreenHeight-ImageHeight) 
       NewYpos=ScreenHeight-ImageHeight   
       Balls(lp).SpeedY=-Balls(lp).SpeedY
    endif

     ; Store this balls position
    Balls(lp).Xpos=NewXpos
    Balls(lp).Ypos=NewYpos


    LifeTimeLeft=Balls(lp).LifeTimer-CurrentTime
    if LifeTimeLeft<0
       DeleteBall(lp)   
    else
       
    ; Check if the ball has less than a second to live
       if LifeTimeLeft<500
         
      Balls(lp).FlashToggle=Mod(Balls(lp).FlashToggle+1,8)

      if Balls(lp).FlashToggle>3
         drawimage ThisIMage,NewXpos-imagewidth,NewYpos-imageheight,1  
      endif
     
      CenterText NewXpos,NewYpos,LifeTimeLeft
      
       else
      ; draw the image to represent this ball    
         drawimage ThisIMage,NewXpos-imagewidth,NewYpos-imageheight,1  
       endif

    endif    


     endif
  next
   
   
EndFunction


; Some Helper Functionsto deals with balls

Function CreateBall(Xpos,Ypos,SpeedX,Speedy)
   ; Get a free Ball Index    
   ThisBall=GetFreeBall()

   ; init it's settimgs 
      Balls(ThisBall).status=True
      Balls(ThisBall).xpos  =xpos

Login required to view complete source code





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kevin

#1
July 02, 2007, 11:11:08 PM Last Edit: April 30, 2013, 12:53:30 PM by kevin
 Here's an alternative version of the above example.    This one uses  GetArrayCells() for to find free indexs within the Balls() array, then it uses the NULL writing to delete a type within the array.


PlayBASIC Code: [Select]
; Make a ball image
  Size=100
  CreateImage 1,Size,Size
  RenderPhongImage 1,Size/2,Size/2,$ffff8f,size*0.9,2.0


; define a ball type
   Type tBall
         Status
         Xpos,Ypos
         SpeedX,SpeedY
           Image
           LifeTimer
           FlashToggle
   EndType

; create an array to house our list of balls
  dim Balls(1) as tBall


; -----------------------------------------
; Main Loop
; -----------------------------------------

Do
   ; Clear the Screen 
   Cls rgb(20,30,40)
   ; Display Controls
  Print "press space to create ball"
     

   ; Call the UpdateBalls() function
  UpdateBalls()
  
   ; Check for space key
  If SPacekey()=true and KeyPress=false

     ; Calc a random starting position for this ball
        Xpos=Rnd(GetScreenWIdth())
        Ypos=Rnd(GetScreenHeight())
   
     ; Create (init) a ball at this position and give it a random speed    
        CreateBall(Xpos,Ypos,NewSpeed(5),NewSpeed(5))

        KeyPress=True

  else
        If SPacekey()=false then KeyPress=false
  endif
   
   Sync   
loop



; this function finds a random speed for a ball axis. 
Function NewSpeed(Max)
   Repeat
        Speed=RndRange(-max,max)   
   Until   Speed<>0
EndFunction Speed



Function UpdateBalls()
   ; run through all   
  ScreenWidth=GetSCreenWidth()
  ScreenHeight=GetSCreenHeight()
   
  CurrentTime=Timer()
   
  For lp=1 to GetArrayelements(Balls().tball,1)
     if Balls(lp).Status=True

    ThisImage=Balls(lp).Image
    ImageWidth      =GetImageWidth(ThisImage)/2
    ImageHeight   =GetImageHeight(ThisImage)/2
    
     ; Move the ball on the X axis
    NewXpos=Balls(lp).Xpos+Balls(lp).SpeedX

     ; Check for Left Edge redbound
    If NewXpos<=ImageWidth 
       NewXpos=ImageWidth   
       Balls(lp).SpeedX=Balls(lp).SpeedX*-1
    endif
     
     ; check for right edge rebound
    If NewXpos=>(ScreenWidth-ImageWidth) 
       NewXpos=ScreenWidth-ImageWidth   
       Balls(lp).SpeedX=Balls(lp).SpeedX*-1
    endif
   
     ; MOve the ball along the y axis
    NewYpos=Balls(lp).Ypos+Balls(lp).SpeedY
     ; Check for Left Edge redbound
    If NewYpos<ImageHeight 
       NewYpos=ImageHeight
       Balls(lp).SpeedY=-Balls(lp).SpeedY
    endif
     
     ; check for right edge rebound
    If NewYpos>(ScreenHeight-ImageHeight) 
       NewYpos=ScreenHeight-ImageHeight   
       Balls(lp).SpeedY=-Balls(lp).SpeedY
    endif

     ; Store this balls position
    Balls(lp).Xpos=NewXpos
    Balls(lp).Ypos=NewYpos


    LifeTimeLeft=Balls(lp).LifeTimer-CurrentTime
    if LifeTimeLeft<0
          DeleteBall(lp)   
         Continue
    Endif
       
    ; Check if the ball has less than a second to live
       if LifeTimeLeft<500
         
      Balls(lp).FlashToggle=Mod(Balls(lp).FlashToggle+1,8)

      if Balls(lp).FlashToggle>3
         drawimage ThisIMage,NewXpos-imagewidth,NewYpos-imageheight,1  
      endif
     
      CenterText NewXpos,NewYpos,LifeTimeLeft
      
       else
      ; draw the image to represent this ball    
         drawimage ThisIMage,NewXpos-imagewidth,NewYpos-imageheight,1  
       endif



     endif
  next
   
   
EndFunction


; Some Helper Functionsto deals with balls

Function CreateBall(Xpos,Ypos,SpeedX,Speedy)
   ; Get a free Array Index within the Balls() array   
   ThisBall=GetFreeCell(Balls())
   

Login required to view complete source code


kevin

#2
July 02, 2007, 11:18:48 PM Last Edit: April 30, 2013, 12:54:07 PM by kevin
 Here's a linked list version.

PlayBASIC Code: [Select]
; Make a ball image
  Size=100
  CreateImage 1,Size,Size
  RenderPhongImage 1,Size/2,Size/2,$ffff8f,size*0.9,2.0


; define a ball type
   Type tBall
         Xpos,Ypos
         SpeedX,SpeedY
           Image
           LifeTimer
           FlashToggle
   EndType

; create a linked list of called BALL of TBALL
  dim Ball as tBall list


; -----------------------------------------
; Main Loop
; -----------------------------------------

Do
   ; Clear the Screen 
   Cls rgb(20,30,40)
   ; Display Controls
     Print "press space to create ball"
     

   ; Call the UpdateBalls() function
  UpdateBalls()
  
   ; Check for space key
  If SPacekey()=true and KeyPress=false

     ; Calc a random starting position for this ball
        Xpos=Rnd(GetScreenWIdth())
        Ypos=Rnd(GetScreenHeight())
   
     ; Create (init) a ball at this position and give it a random speed    
        CreateBall(Xpos,Ypos,NewSpeed(5),NewSpeed(5))

        KeyPress=True

  else
        If SPacekey()=false then KeyPress=false
  endif
   
   Sync   
loop



; this function finds a random speed for a ball axis. 
Function NewSpeed(Max)
   Repeat
        Speed=RndRange(-max,max)   
   Until   Speed<>0
EndFunction Speed



Function UpdateBalls()
   ; run through all   
  ScreenWidth=GetSCreenWidth()
  ScreenHeight=GetSCreenHeight()
   
  CurrentTime=Timer()
   
  For Each Ball()
     
    ThisImage=Ball.Image
    ImageWidth      =GetImageWidth(ThisImage)/2
    ImageHeight   =GetImageHeight(ThisImage)/2
    
     ; Move the ball on the X axis
    NewXpos=Ball.Xpos+Ball.SpeedX

     ; Check for Left Edge redbound
    If NewXpos<=ImageWidth 
       NewXpos=ImageWidth   
       Ball.SpeedX=Ball.SpeedX*-1
    endif
     
     ; check for right edge rebound
    If NewXpos=>(ScreenWidth-ImageWidth) 
       NewXpos=ScreenWidth-ImageWidth   
       Ball.SpeedX=Ball.SpeedX*-1
    endif
   
     ; MOve the ball along the y axis
    NewYpos=Ball.Ypos+Ball.SpeedY
     ; Check for Left Edge redbound
    If NewYpos<ImageHeight 
       NewYpos=ImageHeight
       Ball.SpeedY=-Ball.SpeedY
    endif
     
     ; check for right edge rebound
    If NewYpos>(ScreenHeight-ImageHeight) 
       NewYpos=ScreenHeight-ImageHeight   
       Ball.SpeedY=-Ball.SpeedY
    endif

     ; Store this balls position
    Ball.Xpos=NewXpos
    Ball.Ypos=NewYpos


    LifeTimeLeft=Ball.LifeTimer-CurrentTime
    if LifeTimeLeft<0
         ; Kill This object in the list
          Ball = NULL
         Continue
    Endif
       
    ; Check if the ball has less than a second to live
       if LifeTimeLeft<500
         
         Ball.FlashToggle=Mod(Ball.FlashToggle+1,8)

         if Ball.FlashToggle>3
            drawimage ThisIMage,NewXpos-imagewidth,NewYpos-imageheight,true
         endif
        
         CenterText NewXpos,NewYpos,LifeTimeLeft
      
       else
         ; draw the image to represent this ball    
            drawimage ThisIMage,NewXpos-imagewidth,NewYpos-imageheight,true
       endif


  next
   
   
EndFunction



Function CreateBall(Xpos,Ypos,SpeedX,Speedy)
   ; Get a free Array Index within the Balls() array   
   
      Ball= New tBall
   ; init it's settimgs 
      Ball.xpos  =xpos
      Ball.ypos  =ypos

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