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  1. Replies
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    If you don't need dynamic subdivision, store the...

    If you don't need dynamic subdivision, store the resulting mesh. Either use display lists, or use GLU_NURBS_TESSELLATOR mode with callbacks which store the data, or write your own NURBS tessellator....
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    My first guess would be that there's something...

    My first guess would be that there's something wrong with the normals. Are those being read from the OBJ file, or are they generated?
  3. OpenGL doesn't have any functions with those...

    OpenGL doesn't have any functions with those names.


    glVertexPointer() is a legacy/compatibility function which specifies the data for the vertex position (accessible in a vertex shader via the...
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    Passing the same array for both colour and...

    Passing the same array for both colour and texture coordinates doesn't seem to make much sense.



    The effect is what you would expect if two of the components were either constant or determined...
  5. glDrawArraysInstanced requires OpenGL 3.1. If...

    glDrawArraysInstanced requires OpenGL 3.1. If you're using the ARB_draw_instanced extension, you should be using glDrawArraysInstancedARB.


    For which attributes? The per-instance attributes...
  6. VAOs require OpenGL 3.0 or...

    VAOs require OpenGL 3.0 or ARB_vertex_array_object.

    But they're really not that significant; they just reduce the number of calls required to set up the arrays prior to issuing a draw call. Any...
  7. It sends the matrix. And updating the vertex data...

    It sends the matrix. And updating the vertex data will certainly be more efficient than using one draw call per sprite.

    If the number of sprites is so large that you actually have to worry about...
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    The difficulty isn't in learning to use software,...

    The difficulty isn't in learning to use software, it's in learning to model. In particular, learning to model humans requires some knowledge of anatomy.

    Find an existing model or hire a modeller...
  9. Right; I was looking at revision 3. I had assumed...

    Right; I was looking at revision 3. I had assumed that document revisions were just for typos and the like, and that actual changes to the language would constitute a new language version.
  10. Those are the just values of the enumerants. You...

    Those are the just values of the enumerants. You have to use e.g.


    GLint max_vertices, max_components;
    glGetIntegerv(GL_MAX_GEOMETRY_OUTPUT_VERTICES, &max_vertices);...
  11. According to 4.3.9 of the GLSL 4.5 specification...

    According to 4.3.9 of the GLSL 4.5 specification, the instance name can only have a single subscript:
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    Yes. You'll only want the real part. Actually,...

    Yes. You'll only want the real part. Actually, the complex part may end up being zero due to the definition of H(k,t).


    Right.

    There are FFT algorithms which can perform the transform...
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    I've only scanned the slides briefly, but a few...

    I've only scanned the slides briefly, but a few points:

    Slide 8 gives the formula for the "height" as a function of wavenumber and time: H(k,t). This is the initial (complex) amplitude H0(t)...
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    Either: 1. call glTexImage2D() for each face...

    Either:

    1. call glTexImage2D() for each face and mipmap level, using target parameters of GL_TEXTURE_CUBE_MAP_POSITIVE_X, GL_TEXTURE_CUBE_MAP_NEGATIVE_X, etc, or

    2. call glTexStorage2D() with a...
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    The glBindBuffer() call was made while the VAO...

    The glBindBuffer() call was made while the VAO was bound, so unbinding the element array buffer changes the setting stored within the VAO.

    Also, note that the VAO doesn't store the current binding...
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    You can use glGetAttribLocation() after the...

    You can use glGetAttribLocation() after the program is linked to obtain the index for an attribute, or glBindAttribLocation() before the program is linked to set it to a specific value. Or you can...
  17. Always? No. Doing so may add significant...

    Always? No.

    Doing so may add significant overhead, particularly for reference-based languages such as Java. If you have an array of Vec3, you have to copy the date into a float[] in order to pass...
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    You can also get around it by using a texture. ...

    You can also get around it by using a texture.


    Alternatively, you could use a compute shader for this step.

    And if you're performing interpolation, you really would want to use quaternions...
  19. Calling glBindTexture(GL_TEXTURE_2D,0) in the...

    Calling glBindTexture(GL_TEXTURE_2D,0) in the middle of the function means that the glTexParameter() calls affect the texture which was bound prior to calling the function, while the glTexImage2D()...
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    This is only relevant to the fixed-function...

    This is only relevant to the fixed-function pipeline. It doesn't do anything if you're using a fragment shader, and isn't valid if you're using OpenGL 3+ core profile.


    Unless you called...
  21. I don't see a glBindTexture() call in the text...

    I don't see a glBindTexture() call in the text rendering code; are you overwriting the model texture?
  22. Your pastebin starts with: Compile failure...

    Your pastebin starts with:


    Compile failure in (null) shader:


    I can't match this against anything in your source code, but the (null) is indicative of passing a null pointer for a string.
    ...
  23. FWIW, it compiles fine under WebGL, which is...

    FWIW, it compiles fine under WebGL, which is based upon OpenGL ES 2.0.

    Can you get any shader to compile? If not, that suggests a problem with your client code rather than the shader.
  24. You appear to be trying to read .PNG files as if...

    You appear to be trying to read .PNG files as if they contained raw pixel data. They don't. You'll need to use a library such as libpng to decode the files.
  25. You might try actually checking for errors via...

    You might try actually checking for errors via glGetError().

    E.g. if glCreateShader() fails, the functions which query its state will also fail, meaning that status, param, etc will be unchanged....
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