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: Dan Bartlett

Page 1 of 18 1 2 3 4

Search: Search took 0.01 seconds.

  1. Replies
    2
    Views
    147

    No, unfortunately when I last checked (a year or...

    No, unfortunately when I last checked (a year or 2 ago) it wasn't possible to have negative values. I also wanted to do what you are trying previously, but for streaming certain attributes and not...
  2. Replies
    14
    Views
    1,570

    You're right on the amount of data being used. ...

    You're right on the amount of data being used.

    If the vertex data is the same for each vertex that is shared between triangles, then using indexed drawing (glDrawElements) would help reduce the...
  3. If you're using a 32-bit application, then 32-bit...

    If you're using a 32-bit application, then 32-bit DLLs should be placed into Windows/SysWOW64 rather than Windows/System32 (see http://en.wikipedia.org/wiki/WoW64#Registry_and_file_system ).
  4. Replies
    2
    Views
    503

    This article by Fabian Giesen...

    This article by Fabian Giesen about write-combined memory explains the issue & some guidelines on getting the best performance. Write-combined & non-cacheable memory are explained in section 3.3.3...
  5. Is your line: glUniform1iARB(tex, SLOT); a...

    Is your line:

    glUniform1iARB(tex, SLOT); a forum post typo?
    If not, tex should instead be the uniform location, rather than the texture id.
  6. Replies
    8
    Views
    1,039

    For me glGetTexImage returns all 0's when using...

    For me glGetTexImage returns all 0's when using GL_RGBA32UI (Win8, AMD Catalyst drivers, probably a few months old). Perhaps some part of the spec says using integer textures with glGenerateMipmap...
  7. Replies
    8
    Views
    1,039

    3452816845 (0xCDCDCDCD) seems to be a magic...

    3452816845 (0xCDCDCDCD) seems to be a magic number used by Visual C/C++ to mark uninitialized heap memory.

    Are these values getting filled by the glGetTexImage call, or is glGetTexImage not...
  8. Replies
    3
    Views
    553

    You're passing in the same value for posX, posY &...

    You're passing in the same value for posX, posY & posZ each time you draw the sphere, so will be drawing on the same spot 4 times.
  9. Since you're setting a uniform location as well...

    Since you're setting a uniform location as well as attrib locations, you will need

    #extension GL_ARB_explicit_uniform_location : enable
    as well as

    #extension GL_ARB_explicit_attrib_location :...
  10. Should it be lights.Light[0].type instead of...

    Should it be lights.Light[0].type instead of LightProperties.Light[0].type?
  11. Replies
    5
    Views
    1,145

    You should probably be requesting double...

    You should probably be requesting double buffering and have some error checking in there too, there's an SDL example here that has both that might be of some help.
  12. If your meshes are 100 MB+ the overhead of...

    If your meshes are 100 MB+ the overhead of setting up will be relatively small compared to the draw time. Your wire-frame mode will be very slow as you're making a draw call per triangle, to do it...
  13. Replies
    4
    Views
    711

    Sorry, I meant putting glTexParameteri(target,...

    Sorry, I meant putting

    glTexParameteri(target, GL_GENERATE_MIPMAP_SGIS, GL_TRUE);
    before

    glTexImage2D(target, 0, internalformat, w, h, 0, format, GL_UNSIGNED_BYTE, data);
    but glGenerateMipmap...
  14. Replies
    4
    Views
    711

    Have you tried setting GL_GENERATE_MIPMAP_SGIS =...

    Have you tried setting GL_GENERATE_MIPMAP_SGIS = TRUE before uploading the texture image? I think it only generates the mipmaps once a new image is loaded to the base image after this flag is set. ...
  15. By default OpenGL uses mipmaps for most texture...

    By default OpenGL uses mipmaps for most texture types (except for rectangle textures), so it is expecting you to provide them & since you don't your texture isn't complete. One way to tell OpenGL...
  16. Replies
    7
    Views
    1,129

    GLScene (http://glscene.org) (an open source...

    GLScene (an open source OpenGL Scene Graph for Delphi) has CSG code for meshes and a sample project demonstrating it's use, as well as more basic intersection tests (do 2 objects intersect or not).
    ...
  17. You're passing the context handle in (which is of...

    You're passing the context handle in (which is of type HGLRC), use the same HDC you used to create the context.

    rc = wglCreateContext(dc);
    ...
    extensions = wglGetExtensionsStringARB(dc);
    ...
  18. The buffer bound to GL_ARRAY_BUFFER is used by...

    The buffer bound to GL_ARRAY_BUFFER is used by glVertexAttribPointer (+other gl***Pointer) functions, it isn't actually used by draw calls so has no effect. You need to make the gl***Pointer calls...
  19. Replies
    1
    Views
    579

    The only problem I can see is that NumVertices...

    The only problem I can see is that NumVertices doesn't match the correct number of vertices. You only have 12 vertices listed, but NumVertices = 36. This could cause problems when glDrawArrays...
  20. Replies
    1
    Views
    447

    Searching the web for "axis-angle to euler"...

    Searching the web for "axis-angle to euler" returns this result: http://www.euclideanspace.com/maths/geometry/rotations/conversions/angleToEuler/
  21. Replies
    2
    Views
    792

    To reverse a Euler angle transformation around...

    To reverse a Euler angle transformation around x,y and then z, you need to rotate by the negative angles around z, y and then x. Rotating by the negative angles around x, y then z isn't the reverse...
  22. Replies
    6
    Views
    1,671

    You are setting glShadeModel(GL_FLAT) in one...

    You are setting glShadeModel(GL_FLAT) in one context, but rendering with the other context. Since this state is per-context it never affects rendering. Only certain objects are shared between...
  23. Replies
    8
    Views
    1,754

    You could try a debugging tool, such as AMD's...

    You could try a debugging tool, such as AMD's CodeXL that is capable of stepping through OpenGL calls and seeing the state at each stage.
  24. Replies
    2
    Views
    1,230

    Also, since OpenGL 4.1 / GL_ARB_viewport_array...

    Also, since OpenGL 4.1 / GL_ARB_viewport_array, you can have an array of viewports/scissor rectangles/depth ranges used at the same time (still global). The viewport that is used is controlled by...
  25. Replies
    7
    Views
    2,411

    Maybe you need to use the "invariant" qualifier...

    Maybe you need to use the "invariant" qualifier to ensure your passes produce the same output?
Results 1 to 25 of 445
Page 1 of 18 1 2 3 4