MakeMaskedCircleImage function

[kevin]

 MakeMaskedCircleImage Function


    This function grabs a chunk from another image, then draws a circle to alpha channel to mask out the bits we want, giving up a 007 sort of circle reveal effect



Video:

PlayBASIC Code: [Select]

   screen = makeBackDrop()
   
   setfps 30
   
   do   
      cls $304050
      
      
      
      mx=mousex()
      my=mousey()

      rendertoimage screen      
      mask=MakeMaskedCircleImage(mx,my,50,5)
      rendertoscreen
      
      drawimage mask,mx,my,true

      deleteimage mask

      sync
   loop spacekey()

   
   
   
   
Function MakeMaskedCircleImage(Xpos,Ypos,Size,Pad=5)

      oldinkmode =GetInkmode()      
   
      RadiusX=Size
      RadiusY=Size
      Width   =Pad+(RadiusX*2)+Pad
      Height=Pad+(RadiusY*2)+Pad   
   
      Mask=NewFximage(Width,height,true)
      OldSurface=getsurface()


      Xpos-=Pad
      Ypos-=Pad

      copyrect OldSurface,xpos,ypos,Xpos+Width*2,Ypos+Height,Mask,0,0
   
      rendertoimage Mask
         inkmode 1+512
         Circlec Width/2,Height/2,Size,true,$ff000000   
      
      rendertoimage OldSurface   
      inkmode OldInkMode   
   



EndFunction Mask






Function MakeBackDrop()
   
         Screen=NewFXImage(800,600)
      rendertoimage Screen
      shadebox 0,0,800,600,$112233,$445566,$aa88bb,$332288
      
      loadfont  "veranda",2,100,0
      setfont 2
      centertext 400,240,"Hello World"
      setfont 1
      rendertoscreen
      
      
      rgbmaskimage Screen,$00ffffff
EndFunction Screen