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Type: Posts; User: Yann LE PETITCORPS

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  1. Re: Specific blending mode (how to achieve this?)

    You can certainly use a vertex shader for this ?
  2. Re: Separate sampler state from texture state

    GL_LINEAR or GL_NEAREST of course :)

    But now I see that for mipmapping, we have another typeofsample parameter to use for the magnification (cf GL_*_MIPMAP_*) , so this form seem me more...
  3. Re: Separate sampler state from texture state

    The null or negative value of typeofsample indicate that we have to use the sampler type stored into the texture state.

    => with this, the compatibility with the actual texture2D call is...
  4. Re: Direct GL_YUV, GL_YCbCr or YCoCg texture support ?

    Yes Gedolo, block building support at a lower level (cf. at texture format level) is exactely about what I think.

    Block building seem already to be internaly used into the hardware (cf....
  5. Re: Separate sampler state from texture state

    A lot of thanks for this precision Alfonse :)

    I have found a method where the YCbCr 4:2:0 format is converted to a format that is very more friendly for the hardware interpolation units.

    I...
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    Re: Calculating the inverse matrix

    In shaders, they are gl_ModelViewMatrixInverseTranspose and others like gl_ProjectionInverse that can be used for example.

    If this have to be used outside the shader, I know that we can import...
  7. Re: Separate sampler state from texture state

    Another way is to always use GL_NEAREST, get the 4 surrounding texels at (u,v), (u+1,v) , (u,v+1), (u+1,v+1) in integers positions, and compute ourself the various interpolations that we want into...
  8. Re: Separate sampler state from texture state

    Note that one interpolation is already make here :

    u = (u1+u2)/2.0 - 0.5;
    v = (v1+v2)/2.0 - 0.5;

    The -0.5 is for handle the 0..255 to -128..127 YCbCr->YUV conversion

    I want to interpole...
  9. Re: Separate sampler state from texture state

    It's you that are derailling here ...

    What I want is to have SEPARATE SAMPLER STATE FOR TEXTURE STATE for the y, u et v sampling :


    y = texture2D(tex, vec2( (nx), (ny)*(4.0/6.0) )).r;
    u1 =...
  10. Re: Separate sampler state from texture state

    "Just write the shader code for it"

    In this case, why you don't simply send the shader code in this thread if this is as simple as this ?

    Personnaly, I have already send my YCbCr 4:2:0 shader...
  11. Re: Separate sampler state from texture state

    I'm have begin with OpenGL a lot of years before this century with Linux and the first 3Dfx Vodoo card but this is only since the last year that I have begin to handle video textures in OpenGL...
  12. Re: Separate sampler state from texture state

    But it's usefull because this is already usable :)

    I think that the telephon was primary used for "théâtrophone" no ?

    Now in 2010, we have ADSL with a lot of TV channels arising from this...
  13. Re: Separate sampler state from texture state

    For this time, only for my personnal pleasure :)

    If I follow your same confused reasoning, why to have invented the color TV, the VCD/DVD and others blue-rays/VOD inventions when Eadweard...
  14. Re: Separate sampler state from texture state

    1920x1080 = 240x135 blocs of 8x8 texels

    This make less than 15x9 patchs of 16x16 blocs of 8x8 texels

    So, "only" 16x16=256 "simples/littles" texture units of 8x8=64 texels each
    For handle one...
  15. Re: Separate sampler state from texture state

    Not only playing movies ... display/map numerous video streams on numerous 3D shapes
    => this isn't really the same thing ...
    (but ok, this can begin with playing/mapping 6 movies in // on a cube...
  16. Re: Separate sampler state from texture state

    A 720x576 MPEG2 (cf. DVD) video texture support at 25/30/50/60 fps can be a good start, no ???

    And I'm for a 4096x4096 MPEG4 video texturing at 100 000 fps on another side :)
    But after ...
    ...
  17. Re: Separate sampler state from texture state

    Yes, Chris I think exactely the same thing :)

    But I think too that the "bind texture by unit" is good for maintain compatibility with olders versions of OpenGL that use multiples chained...
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    Re: Texture Compression => DXT YCbCr 4:2:0 ???

    I think to have found 3 news DXT compressions algorithms :)

    They works with a bloc of 16 pixels (4x4) such as DXT1/2/3/4/5/6

    But this is computed in the YCbCr color domain, not in the RGB...
  19. Re: Separate sampler state from texture state

    Thanks Alphonse, I have now **really** understand that a sampler and a texture unit is exactely the same thing :)
    (I understand quickly but it must sometimes explain to me a long time :) )

    For a...
  20. Re: Separate sampler state from texture state

    I have reread this thread :

    glActiveTexture(GL_TEXTURE0);
    glBindTexture(GL_TEXTURE_2D, TextureName);
    glBindSampler(GL_TEXTURE_2D, SamplerName0);

    seem me good .. but it cannot handle more...
  21. Re: Separate sampler state from texture state

    Yes, Alphonse it's true.

    I have only found this problem with very old hardware :)
    (and that cannot handle shaders, so I have resolved this at the source with a YCbCr to RGB conversion in software...
  22. Re: Separate sampler state from texture state

    Thanks, Skynet for your response

    It's about the possibility of multiples samplers into the same texture unit that I have wanted to speak. (it's true that I make often the mistake :( )

    But...
  23. Re: Separate sampler state from texture state

    I like the idea about to have the possibilty to use different samplers on the same texture unit :)

    I know that this can be easily handle with multiples textures, but it's true that the...
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    Re: Texture Compression

    Hi,

    I begin to have something that work and have the same 8:1 compression rate such as DXT1 but with a quality that seem to me really better with photographics, statics and animated pictures.
    (my...
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    Re: Texture Compression

    Thank Mark DS,

    Your link is really good and I have find a lot of code/samples/new ideas in it

    This confort me to the fact that the RGB colorspace isn't the best for the...
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