UnderwareDESIGN

 This tidbit creates a 320*240 FX screen,  draws a bunch of alpha additive circles on it, then renders(scales) the FXscreen to the PB screen.  


[pbcode]
   W=320
   h=240

   OpenScreen 640,480,32,2

   FXScreen=NewFXImage(w,h)

   

   Do
   
      RenderToIMage FXScreen

      BackDrop()

      inkmode 1+64

      y=h*0.25

      radius=w/4
      For Angle#=0 to 359 step 3
         BaseX#=(w/2)+Cos(BaseAngle#+Angle#)*Radius
         BaseY#=(h/2)+Sin(BaseAngle#+Angle#)*Radius
         Circlec BaseX#,Basey#,40+(angle#*0.25),true,rgb(2,3,4)
      next

      BaseAngle#=wrapangle(BaseAngle#,1)

      ShowImage(FXScreen)   

      FXs$   =str$(W)+"*"+str$(h)
      Ds$   =str$(GetScreenWidth())+"*"+str$(GetScreenHeight())
      Text 10,10,"FX Screen:" +FXS$
      Text 10,20,"  Display:" +Ds$
      text 10,40,Fps()      

      Sync
   loop



Function ShowIMage(Img)
   rendertoScreen

   SW=getScreenWidth()
   SH=getScreenHeight()

   iw=getImageWidth(img)
   ih=getImageHeight(img)
   
   TextureQuad img,0,0,0,0,_
               sw,0,iw,0,_
               sw,sh,iw,ih,_
               0,sh,0,ih,false

EndFunction




function BackDrop()
   Static baseangle#
   c1=RGBFade($ff0000,SinNewValue(50,baseangle#,50))
   c2=RGBFade($ffff00,CosNewValue(50,baseangle#,50))

   c3=RGBFade($ff00f0,SinNewValue(50,baseangle#*2,50))
   c4=RGBFade($1234,CosNewValue(50,baseangle#*2,50))
   
   ShadeBox 0,0,GetSurfaceWidth(),GetSurfaceHeight(),c1,c2,c3,c4
   baseangle#=Mod(baseangle#+1,360)
EndFunction
 
[/pbcode]

Hey thats a crazy cool background effect :) nuts if I'll ever figure it out though. I get how the scaling works though