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: James W. Walker

Page 1 of 5 1 2 3 4

Search: Search took 0.00 seconds.

  1. ATI FireGL V7700 driver crash involving glBlitFramebuffer

    I'm getting a driver crash (brings down video on the whole PC), and I expect it's probably a driver bug, but I thought I'd post it on the off chance that someone knows a workaround. The rough...
  2. Replies
    0
    Views
    718

    ChoosePixelFormat crash

    I have a PC running 64-bit Vista, with an ATI Radeon HD 4670. I updated the graphic driver to the latest available from AMD, which is from early 2011. Now, if I run a test app under Microsoft's...
  3. I'm still banging my head against this one. I...

    I'm still banging my head against this one. I have noticed that if I don't call wglShareLists when I create my contexts, the error goes away. However, I've been trimming out stuff until there is...
  4. For what it's worth, when the error happens I...

    For what it's worth, when the error happens I read the source back with glGetShaderSource and write it to a log file, and it looks OK.
  5. Intermittent shader compile error with unhelpful info log

    I've been getting occasional errors compiling a vertex shader. It's the same vertex shader that usually works, on the same hardware, so I don't think the GLSL code could really be bad. The info log...
  6. Re: glPushAttrib/glPopAttrib side effects?

    Well, I've never used glEnableVertexAttribArray, just old-school vertex/normal/uv arrays.
  7. glPushAttrib/glPopAttrib side effects?

    I'm trying to track down a rendering problem that only seems to happen with Intel graphics cards. (Objects that should be colored sometimes appear white.) I discovered that if, at a certain point...
  8. Replies
    28
    Views
    11,589

    Re: Performance of texture upload with PBO

    OK, maybe I can answer my own question about why use PBO if you're going to use threads. I guess the simpler approach would not work well if you have only one processor, because while...
  9. Replies
    28
    Views
    11,589

    Re: Performance of texture upload with PBO

    yooyo, thanks, but there are a couple of things that still confuse me.

    First, when I started this topic, I referred to an example in the PBO specification, and that example did not use threads. ...
  10. Replies
    28
    Views
    11,589

    Re: Performance of texture upload with PBO

    I managed to get Visual Studio to build me a DLL using the SSE2 memory copy function. I made sure it was compiled with optimizations and intrinsics, and verified that it was taking the SSE2 code...
  11. Replies
    28
    Views
    11,589

    Re: Performance of texture upload with PBO

    Hmm, Visual Studio is also giving me an error on __sse2_available. I suppose I need to include some header, but what? My Google-fu has failed me.
  12. Replies
    28
    Views
    11,589

    Re: Performance of texture upload with PBO

    Looks like my old CodeWarrior compiler can't cope with this. It has never heard of __sse2_available, and gave a bunch of "register spilled" warnings that I didn't know how to deal with. I commented...
  13. Replies
    28
    Views
    11,589

    Re: Performance of texture upload with PBO

    I guess I wasn't clear... when I said "the thread at your first link refers to code at a dead link", I didn't mean that your link was itself a dead link, I meant that the thread is talking about code...
  14. Replies
    28
    Views
    11,589

    Re: Performance of texture upload with PBO

    I tried the AMD assembly code, and it may be a tad faster, say 12.9 ms rather than 13.5.
  15. Replies
    28
    Views
    11,589

    Re: Performance of texture upload with PBO

    D'oh! I now see that CopyMemory is a macro defined to be RtlCopyMemory, and RtlCopyMemory is a macro defined to be memcpy! So maybe Microsoft doesn't have any memory-copy function in a DLL, just a...
  16. Replies
    28
    Views
    11,589

    Re: Performance of texture upload with PBO

    Thanks, but the thread at your first link refers to code at a dead link, and an Intel library that was then available for free but is no longer. The second link is designed for AMD processors, and...
  17. Replies
    28
    Views
    11,589

    Re: Performance of texture upload with PBO

    I did leave out some relevant details. My image data actually contains 2 side by side images, and I'm uploading each half to separate textures. I realize now that I can be a little smarter and...
  18. Replies
    28
    Views
    11,589

    Re: Performance of texture upload with PBO

    Now I'm more confused... I did the timing again, with a somewhat bigger image size (1920 x 1080) and got very different results: about 13.5 ms for the memcpy, but only 0.1 ms for glTexSubImage. ...
  19. Replies
    28
    Views
    11,589

    Re: Performance of texture upload with PBO

    That's what I've read, but as stated above, that's not what I measured. So even if I could do the memcpy in zero time, I still wouldn't have a win.
  20. Replies
    28
    Views
    11,589

    Performance of texture upload with PBO

    In the ARB_pixel_buffer_object specification, Example 2 shows a way to upload texture data using a PBO. The basic outline is that you create a PBO of the right size, map the PBO into memory, copy...
  21. Re: checking extensions that your video card supports

    It's free and does the job, what's not to like?

    if you happen to be on a Mac, the Apple developer tools include an app called "OpenGL Driver Monitor" that can show video card capabilities, but I...
  22. Replies
    7
    Views
    5,618

    Re: Emulating glShadeModel( GL_FLAT )?

    Cool, the derivative trick works, so now I can get flat shading on any machine that supports GLSL at all. Thanks!
  23. Replies
    7
    Views
    5,618

    Re: Emulating glShadeModel( GL_FLAT )?

    Interesting. I assume you mean it's been shipping on the Mac for some video cards, as I see it on one of my Macs and not the other (both running Snow Leopard).
  24. Replies
    7
    Views
    5,618

    Re: Emulating glShadeModel( GL_FLAT )?

    Ah. Looks like I'm out of luck, because I'm on the Mac, and so far Apple only supports GLSL 1.20. The "flat" qualifier came in with GLSL 1.30. Thanks anyway.
  25. Replies
    7
    Views
    5,618

    Emulating glShadeModel( GL_FLAT )?

    How would a shader program emulate glShadeModel( GL_FLAT )? I'm not using vertices with varying colors, so it's a question of how to make the lighting constant across a triangle.
Results 1 to 25 of 114
Page 1 of 5 1 2 3 4