0 Replies Latest reply on Dec 6, 2012 9:37 PM by grahammather

    texture size on GPU

    grahammather

      I have a 2048x2048 png spritesheet.  It's 1.7M on disk:

       

      administrators-MacBook-Pro-2:fast_heavy_1 graham$ ls -lah fast_heavy_1.png

      -rw-r--r--  1 graham  staff   1.7M Dec  5 10:25 fast_heavy_1.png

       

      I ran the following command:

       

      administrators-MacBook-Pro-2:fast_heavy_1 graham$ png2atf -c p -e -i fast_heavy_1.png -o fast_heavy_1.atf

      .

       

       

      [In 2730KB][Out 2730KB][Ratio 100.002%][LZMA:0KB JPEG-XR:2730KB]

       

       

      Now it's 2.7M on disk:

       

      administrators-MacBook-Pro-2:fast_heavy_1 graham$ ls -lah fast_heavy_1.atf

      -rw-r--r--  1 graham  staff   2.7M Dec  6 17:04 fast_heavy_1.atf

       

      Now I build a test app built on Starling that uploads just that one texture to the GPU and run it on my iPhone.  I run it and connect to Scout and see the texture taking exactly 6 Megs of GPU memory:

       

      Screen Shot 2012-12-06 at 9.32.39 PM.png

      I'm confused.  Is this normal?  I don't understand what's happening to the PVRTC texture during the upload process that it's going from 2.7M to using 6M.  Is this a reporting error in Scout?  Is there a minimum block of GPU memory that gets allocated for a texture? Is there another tool I can use to independently verify Scout's numbers?