Screen/Image Direct Memory Access

[kevin]

 This Tidbit shows how you can use GetImagePtr to access the backbuffer directly.

PlayBASIC Code: [Select]

ScreenWidth      =640
ScreenHeight   =400

openscreen ScreenWidth,ScreenHeight,32,1


Dim Ptr as pointer

if GetScreenDepth()=32
   Lockbuffer
   Ptr =getimageptr(0)
   Pitch =getimagepitch(0)
   Depth =getimagedepth(0)

      For ylp=0 to ScreenHeight-1
         Dim LinePtr as integer pointer
         LinePtr =Ptr+Ylp*Pitch
         For xlp=0 to ScreenWidth-1
            *LinePtr=rgb(ylp,xlp*ylp,xlp)   
            LinePtr=LInePtr+1
         next
      next
   UnLockbuffer
endif
print int(ptr)
print Pitch
print depth

sync
waitkey