Results 1 to 5 of 5

Thread: Texture Compression and byte sized verts.

  1. #1
    Junior Member
    Join Date
    Jun 2004
    Location
    UK
    Posts
    5

    Texture Compression and byte sized verts.

    Hi all,
    This is more of a standards question than a how-to question. Can I assume that texture compression and byte sized vertices are supported by all OpenGL ES implementations?
    I'm a little confused by the different types of extension flavours (ARB/EXT/ES specific / Core). I'd appretiate some clarification as I'm working on mobile devices that would really benefit from textures compression / byte verts to save memory. It would be nice if I could assume they have both features.

    Thanks,

    Steve.

  2. #2

    Re: Texture Compression and byte sized verts.

    Hi Steven.

    Yes, byte vertices and texture compression are mandatory features for any OpenGL ES 1.0 conformant implementation. The only mandated texture compression format though is paletted texture format (4-bit and 8-bit indices).

    --jani;

  3. #3
    Junior Member
    Join Date
    Jun 2004
    Location
    UK
    Posts
    5

    Re: Texture Compression and byte sized verts.

    Fantastic, that's made my life a whole of easier, thanks Jani.

  4. #4
    Junior Member
    Join Date
    Jun 2004
    Location
    UK
    Posts
    5

    Re: Texture Compression and byte sized verts.

    Has anyone actually use the byte vertices for UVs? How does the mapping work? Does 128,128 represent the equvalent of 1.0f,1.0f?

    thanks,

    Steve.

  5. #5
    Senior Member
    Join Date
    Sep 2003
    Location
    Seattle, WA
    Posts
    246

    Re: Texture Compression and byte sized verts.

    Just checked the reference implementation to be sure:

    No, it represents -128.00 (GL_BYTE is signed). However you can set the texture transformation matrix to scale the coordinates to the range that you need before going into rasterization.

    - HM

    [ June 17, 2004: Message edited by: Hans-Martin Will ]

Similar Threads

  1. Question About the Texture Compression
    By essential in forum OpenGL ES general technical discussions
    Replies: 1
    Last Post: 07-12-2006, 01:15 AM
  2. byte/short vertex/texture coordinate
    By murphychen in forum OpenGL ES general technical discussions
    Replies: 3
    Last Post: 02-16-2005, 05:38 AM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •