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: Jan

Page 1 of 20 1 2 3 4

Search: Search took 0.02 seconds.

  1. Replies
    4
    Views
    2,657

    Sorry for not replying earlier, my internet...

    Sorry for not replying earlier, my internet connection gave up on me...

    @michagl: Yes, that's exactly what I'm doing.

    @dukey: My render target is square and power-of-two (usually 512*512). I...
  2. Replies
    4
    Views
    2,657

    AMD: glGenerateMipmap weirdnesses

    Hi

    This is just to let some people know, maybe for AMD to look into this:

    glGenerateMipmap on AMD cards acts kinda weird. First of all, you definitely MUST have the filtering mode set to...
  3. Replies
    11
    Views
    4,731

    Re: OpenGL / Direct3D projection matrices

    That was my thinking too. However, isn't the projection matrix actually what 'defines' the near and far plane? I mean, OpenGL should clip everything away that's not in the unit-cube. So I would have...
  4. Replies
    11
    Views
    4,731

    Re: OpenGL / Direct3D projection matrices

    I am currently in the process of cleaning up our engine's math code and I stumbled across this odd behavior. I want to make it right, but I am confused as to why it actually currently works. The...
  5. Replies
    11
    Views
    4,731

    Re: OpenGL / Direct3D projection matrices

    That is a very interesting presentation, thank you!

    However, it does not address my problem at hand. We ARE using a projection matrix that transforms everything to [0;1] range instead of [-1;1]...
  6. Replies
    11
    Views
    4,731

    OpenGL / Direct3D projection matrices

    Hi there

    Just trying to wrap my head around the differences in the transformations in OpenGL and D3D.

    As far as I know OpenGL usually transforms z into the range [-1;1] and then later on maps...
  7. Replies
    58
    Views
    69,136

    Re: Official feedback on OpenGL 4.2 thread

    "glDrawElementsInstancedBaseVertexBaseInstance" - Just Wow.


    Nice to see that OpenGL is still updated regularly and more and more details are fleshed out to make ones lives easier. But that's...
  8. Replies
    7
    Views
    2,695

    Re: The nature of GL_POINT

    No. OpenGL 3.0 tried to do away everything that could be "difficult" to support.

    I am not sure, if points are really rendered as triangles, because contrary to triangles, points are ALWAYS...
  9. Replies
    0
    Views
    670

    GLIM Version 0.4 released

    Hi there

    I just realized that it has been much over a year that I have posted an update to the GLIM-libray. So I just uploaded the current code which includes some important bug-fixes.

    GLIM...
  10. Replies
    3
    Views
    2,802

    Re: Detecting if a vertex is concave or reflexive.

    Yeah, that should work too.
  11. Replies
    3
    Views
    2,802

    Re: Detecting if a vertex is concave or reflexive.

    I don't know of a *standard* way, but here is what I'm doing:

    First you need some "reference", to know which vertices are really on the convex hull. Simply compute the bounding box of the polygon....
  12. Thread: Ptex extension

    by Jan
    Replies
    20
    Views
    8,592

    Re: Ptex extension

    Well, if you see it like that... OpenGL NEVER gave any reliable guarantees about memory usage. We can't even query the amount of available memory of a GPU through GL, because we are not supposed to...
  13. Replies
    14
    Views
    3,781

    Re: Replacement of evaluators in OpenGL3.3 and above

    Well, you do have several options.
    * You could do it all manually on the CPU.
    * You could do it with geometry shaders.
    * You could always upload a very high-res mesh with some additional...
  14. Thread: Ptex extension

    by Jan
    Replies
    20
    Views
    8,592

    Re: Ptex extension

    "incomplete mipmap-pyramids" ? You do know that you can cut off the mipmap pyramid at some level, do you?

    Just use glTexParameteri with GL_TEXTURE_BASE_LEVEL and GL_TEXTURE_MAX_LEVEL.

    Other...
  15. Replies
    14
    Views
    3,781

    Re: Replacement of evaluators in OpenGL3.3 and above

    I didn't mean that you need to use tesselation shaders, I only meant that searching for tesselation should give you ideas how to do the math (in the end it's usually some kind of beziér curve etc.)
    ...
  16. Replies
    14
    Views
    3,781

    Re: Replacement of evaluators in OpenGL3.3 and above

    I never bothered to really look at evaluators, but weren't they supposed to do similar stuff, that tesselation does now? Only more hardwired? If so, searching for resources about tesselation might...
  17. Replies
    7
    Views
    2,118

    Re: View changes in 3.3

    Just google for gluPerspective etc. and you should find pages that show the (pseudo) code how they create the matrices.

    Copy&Paste that into your own project and voila you can create those...
  18. Replies
    113
    Views
    98,578

    Re: Curious to who is sticking with OpenGL now...

    I made my renderer compatible to D3D11, so that now I can select which API I want to use. Surprisingly, once you did that, you stop thinking much about the API (because you are always working with an...
  19. Replies
    4
    Views
    2,045

    Re: debug output extension : is it working ?

    AFAIK this extension was promoted by AMD, so nVidia might not really implement it, at all.

    And even on ATI cards, as far as I know, right now it only reports the current errors (INVALID_OP,...
  20. Replies
    1
    Views
    3,170

    Re: Modern polygon triangulation

    https://code.google.com/p/poly2tri

    Very easy to use. It only handles 2D polygons, but of course it's trivial to extend that to 3D manually.

    Jan.
  21. Replies
    5
    Views
    2,316

    Re: NV: Problems using integer attributes

    Yes, it works now.

    Thank you both very much, that was very helpful.

    Cheers,
    Jan.
  22. Replies
    5
    Views
    2,316

    Re: NV: Problems using integer attributes

    Damn! Neither did I know that, nor did I notice that extra "I"!

    I will try that immediately.

    Jan.
  23. Replies
    5
    Views
    2,316

    Re: NV: Problems using integer attributes

    Yep:

    int iArray = getVertexAttribBindPoint (Program, "somename");
    glEnableVertexAttribArray (iArray);
    glVertexAttribPointer (iArray, 1, GL_INT, false, 0, BUFFER_OFFSET (offset));

    Replacing...
  24. Replies
    5
    Views
    2,316

    NV: Problems using integer attributes

    Hi

    I want to pass an integer as an attribute into a shader, which is then used to index a uniform. However, it seems to fail on my nVidia card and garbage is returned.

    However, once i switch to...
  25. Replies
    14
    Views
    4,740

    Re: Nested functions, aborting!

    I was once told by someone from nVidia that C9999 errors are not supposed to happen and are considered to be compiler-errors.

    I once had one myself, and nVidia was extremely quick to take a look...
Results 1 to 25 of 500
Page 1 of 20 1 2 3 4