PS3 Texture Swizzling

mike123mike · Post by **mike123mike** » Tue Jul 08, 2008 3:34 am

Hey,

I wondered if anyone has any experience with ps3 texture swizzling. All methods I find which swizzle 16*8 blocks do not work.

Any help would be appreciated
thanks
Mike

IronPeter · Post by **IronPeter** » Wed Jul 09, 2008 4:06 am

As far as I know NVidia uses bit-mixing for u, v. So odd bits are taken from u, even from v.

This code ( untested ) must work.

Code: Select all


typedef struct Tex
&#123;
    uint8_t pixs&#91;128 * 128&#93;&#91;4&#93;;    
&#125;;

uint8_t *GetPixel&#40; struct Tex *tex, int i, int j &#41;
&#123;
    int address = 
    
    &#40; &#40; i & 1 &#41; << 0 &#41; + &#40; &#40; j & 1 &#41; << 1 &#41; +
    &#40; &#40; i & 2 &#41; << 1 &#41; + &#40; &#40; j & 2 &#41; << 2 &#41; +
    &#40; &#40; i & 4 &#41; << 2 &#41; + &#40; &#40; j & 4 &#41; << 3 &#41; +
    &#40; &#40; i & 8 &#41; << 3 &#41; + &#40; &#40; j & 8 &#41; << 4 &#41; +
    &#40; &#40; i & 16 &#41; << 4 &#41; + &#40; &#40; j & 16 &#41; << 5 &#41; +
    &#40; &#40; i & 32 &#41; << 5 &#41; + &#40; &#40; j & 32 &#41; << 6 &#41; +
    &#40; &#40; i & 64 &#41; << 6 &#41; + &#40; &#40; j & 64 &#41; << 7 &#41;;
    
    return &tex->pixs&#91;address&#93;&#91;0&#93;;
&#125;

_protytype_ · Post by **_protytype_** » Thu Jul 17, 2008 8:28 am

Here is an interesting email exchange between two programmers at insomniac games about swizzling textures on the ps3. They manage to get it done in an insanely low amount of instructions:

http://www.insomniacgames.com/tech/arti ... llcode.php

You guys should check regularly on their R&D subsection, they have lots of articles specific to the ps3 and coding on the spus.