Part of the Khronos Group
OpenGL.org

The Industry's Foundation for High Performance Graphics

from games to virtual reality, mobile phones to supercomputers

Search:

Type: Posts; User: mbentrup

Page 1 of 11 1 2 3 4

Search: Search took 0.02 seconds.

  1. Replies
    17
    Views
    2,077

    No that means that an OpenGL implementation that...

    No that means that an OpenGL implementation that advertises SSBO support must return at least 16MB when you ask for GL_MAX_SHADER_STORAGE_BLOCK_SIZE.
    You can assume that the memory allocated for the...
  2. Replies
    7
    Views
    1,939

    This is only true if the scaling factor is 1 or...

    This is only true if the scaling factor is 1 or -1, so only rotations and mirroring is allowed.



    This is a function definition which may not be placed inside the main() function. You can put...
  3. Up to OpenGL 3.0 every OpenGL release included...

    Up to OpenGL 3.0 every OpenGL release included all functions of the prior releases. For OpenGL 3.1 the ARB decided to remove a bunch of functions and changed the semantics of some others, but it...
  4. The dot product of two vectors is the cosine of...

    The dot product of two vectors is the cosine of the angle between the vectors multiplied by the lengths of each vector. If the vector lengths are arbitrary, you cannot imply anything about the...
  5. Replies
    7
    Views
    2,230

    You seem to be using GLEW, note that current GLEW...

    You seem to be using GLEW, note that current GLEW doesn't work properly with OpenGL core contexts.
  6. Those are the character codes of '0', '1' and...

    Those are the character codes of '0', '1' and '2'. Try
    printf("%d\n", '0');
  7. Replies
    3
    Views
    918

    Yes, that is generally correct. However, there...

    Yes, that is generally correct. However, there are some points you have to consider:

    - the FPS increase only until another stage becomes the bottleneck. If your VS and FS stages for example are...
  8. Your switch statement is incorrect, you compare...

    Your switch statement is incorrect, you compare the int i to the character constants '0', '1' and '2'. That way you'd have to pass 48, 49 and 50 for light 0, light 1 or light 2.

    You should just do...
  9. Replies
    13
    Views
    3,109

    You don't access the VBO, you access the memory...

    You don't access the VBO, you access the memory that it is mapped to, and all threads in a process share their memory. You have to be careful regarding synchronization, but otherwise it is perfectly...
  10. Replies
    13
    Views
    3,109

    You could map/unmap the VBOs from the main thread...

    You could map/unmap the VBOs from the main thread and just fill in the data from the worker threads.
  11. Replies
    5
    Views
    1,327

    You pass 0-based pointers in...

    You pass 0-based pointers in glVertexAttribPointer, but at that time no VBO is bound to GL_ARRAY_BUFFER, so the address is not the start of your VBO, but the start of CPU memory, which is usually not...
  12. Replies
    4
    Views
    1,596

    try -I./include/GL (notice the "." before the...

    try -I./include/GL (notice the "." before the first "/")
  13. Replies
    19
    Views
    2,952

    The color gradient is not produced by the...

    The color gradient is not produced by the shaders, it is part of the rasterization process.

    The shader has some limited influence on the interpolation, it can choose between three interpolation...
  14. Replies
    1
    Views
    688

    gl3w exposes only the functions of the OpenGL...

    gl3w exposes only the functions of the OpenGL core profile, so you have to either upgrade your code to modern OpenGL or use a wrapper supports the compatibility profile, like GLEW.
  15. Floating point precision is 23 bits, that is a...

    Floating point precision is 23 bits, that is a resolution of 0,000244141 pixels on a 2k screen, so it is unlikely that you see any floating point precision issues.

    The more likely issue is that...
  16. I don't really understand what you mean by empty,...

    I don't really understand what you mean by empty, a region of constant color ?

    However, all TC formats have a fixed compression ratio, the compressed size of an "empty" texture is exactly the same...
  17. Replies
    7
    Views
    3,382

    By the way, you seem to use a float uniform where...

    By the way, you seem to use a float uniform where a bool uniform would be more appropriate. If the driver knows that there are only 2 possible input values it can compile two shader variants to avoid...
  18. Replies
    22
    Views
    7,035

    Well, actually the trend in graphics APIs (Metal,...

    Well, actually the trend in graphics APIs (Metal, DX12, glNext) is to go away from abstraction, closer to the hardware.
  19. Replies
    3
    Views
    1,092

    If you don't have ARB_shader_stencil_export, you...

    If you don't have ARB_shader_stencil_export, you can still write a specific value to the stencil buffer in ceil(log2(N)) passes, if you write one bit of the stencil per pass. However, I'd just use a...
  20. I think every driver keeps a flag per texture...

    I think every driver keeps a flag per texture that is set on validation and reset on modification, so that further validations are not done until the texture is changed.
  21. On old GPUs the FP implementation is not always...

    On old GPUs the FP implementation is not always IEEE compliant, but as far as i know that non-compliance is mostly in areas like NaNs and denormal number handling. You can assume that the floats have...
  22. EGL ? It already has the means to load various...

    EGL ? It already has the means to load various APIs and I guess vendors shipping EGL for their products will have to work on a common EGL ABI for Windows anyway.
  23. Replies
    6
    Views
    2,344

    ASTC can encode one- and two-channel images, but...

    ASTC can encode one- and two-channel images, but you have to encode them as luminance resp. luminance+alpha and the HDR range is basically FP16, I think that is the same range as BPTC.
  24. The first thing I'd do would be to look into the...

    The first thing I'd do would be to look into the KHR_debug output, Nvidia may give some hints if the shader hits a slow path.
  25. Replies
    3
    Views
    1,330

    Small nitpick: vertex attributes are not...

    Small nitpick: vertex attributes are not flat-shaded, only varyings can be flat-shaded.

    Another way to implement clipping of primitives is to use (drumroll) vertex clipping. Just write the four...
Results 1 to 25 of 251
Page 1 of 11 1 2 3 4