Convert Text into an AFX image

[kevin]

   This function converts a text message into an AFX image.  AFX formatted images support Alpha channel (32bit only)  so you can get an Anti Aliased look when rendering text to Video or FX formatted surfaces.  The AFX format is only support via drawimage though.

  Since window text is anti aliased by default, All the function does is created a video image (black) and renders the text message to that in pure white.  This creates a gray scale representation of the message.  So we can then take any channel we like and use that as the alpha channel (in this case it uses the blue).   Probably best to precalc a bunch of these in your games though  

PlayBASIC Code: [Select]

   Size=75

   MyFont=LoadnewFont("Arial",Size,0)
   Setfont MyFont

   t$="www.PlayBasic.com"

   ; Convert that Row into a FX image with Alpha channel support (32bit only!)
   i=COnvertTextToAFXimage(t$,Rgb(0,255,0))

   
   Xpos=50
   Ypos=300


   Do
      Cls rgb(100,40,140)   
   
         inc  Frames

   
         t=timer()
            text Xpos,Ypos,t$
         tt1#=tt1#+(timer()-t)
   
         t=timer()
            drawimage i,Xpos,Ypos+Size,true
         tt2#=tt2#+(timer()-t)



         ; 
         print "Speed"
         print tt1#/frames
         print tt2#/frames
   
      Sync         
   loop




Function ConvertTextToAFXimage(t$,TextColour)
   OldSurface=getSurface()

      tw=gettextwidth(t$)
      th=gettextheight(t$)

   
      ThisImage=NewImage(tw,th)
      RenderToIMage ThisImage
      ink rgb(255,255,255)
      text 0,0,t$   

      PrepareAFxImage ThisImage

      r=rgbr(textCOlour)
      g=rgbg(textCOlour)
      b=rgbb(textCOlour)
   
      RenderToImage Thisimage
      lockbuffer
         NullPixel=Point(0,0)   
         For Ylp=0 to Th
            For Xlp=0 to Tw
               ThisRGB=FastPoint(Xlp,yLp)      
               dotc xlp,ylp,argb(RgbB(ThisRGB),R,G,B)      
            next
         next   
      unlockbuffer
   rendertoimage OldSurface
EndFUnction ThisImage

NOTE: This is obsolette, today we use  PlayFONT to create Compressed Raster Fonts for PlayBASIC V1.64 versions.

[Adaz]

Please notice the differences between 1.63v and 1.71g screenshots and FPS values.
Why?


remark: the bottom image is not anti aliased at all

[Big C.]

Hi Kevin,

in the last Beta Help package I didn't find a "Help on Keyword" site for the command PrepareAFXImage... If you examine the latest history.txt you will found that this command was included with Version 1.48c of PlayBasic... Need for PB LE?

[kevin]

    The AFX format is not officially supported and obsolete in 1.7x higher revisions.  Why ? - because not all rendering methods have a AFX render mode.