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Type: Posts; User: Spoops

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    No, Float.MIN_VALUE is the smallest number > 0....

    No, Float.MIN_VALUE is the smallest number > 0. It should be -Float.MAX_VALUE or Float.NEGATIVE_INFINITY (used with Float.POSITIVE_INFINITY).

    However Carmine's solution looks prettier (but you...
  2. Beyond Porting by Cass Everitt covers costs of...

    Beyond Porting by Cass Everitt covers costs of state changes and resource bindings : 2335

    Full slides here.
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    Yes, this is correct. sRGB -> linear is x^2.2,...

    Yes, this is correct. sRGB -> linear is x^2.2, and linear -> sRGB is x^(1/2.2).
  4. Use FBOs...

    Use FBOs; they are basically off-screen render targets. Use one smaller than your window dimensions and use the resulting texture on a fullscreen quad.
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    You should use separate shaders. Do a single pass...

    You should use separate shaders. Do a single pass for all non-scrolling objects, and another one for scrolling objects.
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    glTexParameteri(GL_TEXTURE_2D,...

    glTexParameteri(GL_TEXTURE_2D, GL_GENERATE_MIPMAP, GL_TRUE);

    This is deprecated : Use glGenerateMipmap() instead, after glTexImage2d().
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    Don't put OpenGL code in...

    Don't put OpenGL code in constructors/destructors. You are not guaranteed that they won't be called multiple times on what you see as a single instance (when using arrays or stl containers). Move...
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    I had a similar problem once because the last row...

    I had a similar problem once because the last row of the model matrix wasn't (0,0,0,1). Check your matrices, or send a 3x4 matrix instead.
  9. Why is glBindTexture(GL_TEXTURE_2D, textureID);...

    Why is glBindTexture(GL_TEXTURE_2D, textureID); commented out in loadTexture ? The subsequent glTexImage and glTexParameter calls won't work if the texture is not bound.
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    Depends on the implementation but more often than...

    Depends on the implementation but more often than not, a matrix is actually N times a vector (N being the number of rows). Matrix multiplication is thus N times a dot product.
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    Interesting. You should report this bug to your...

    Interesting. You should report this bug to your graphics card vendor: Nvidia, AMD, Intel
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    To give you an idea of OpenGL support and to help...

    To give you an idea of OpenGL support and to help you make a better decision:

    OpenGL 2.x is available virtually anywhere. Graphics cards came out in 2004-2005, and even 2006 Intel chips have...
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    I meant that using renderbuffers discards some...

    I meant that using renderbuffers discards some outputs of a rendering pass, something that still has to be computed in the fragment shader. Why do you need an attachment if you won't use the data...
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    What do you use renderbuffers for? You should see...

    What do you use renderbuffers for? You should see them as write-only FBO attachments, if you know you won't sample the resulting image afterwards. It's intriguing me that you use multiple...
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    I know that Nvidia drivers are permissive and...

    I know that Nvidia drivers are permissive and allow things to be rendered on screen even if there was an OpenGL error, but it could be the case with Intel too. Check with APItrace or glIntercept to...
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    I'd recommend using OpenCV, it has an OpenCL...

    I'd recommend using OpenCV, it has an OpenCL implementation and is better to use than implementing computer vision algorithms yourself.
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    You can do it simpler : vec3 pt =...

    You can do it simpler :



    vec3 pt = (invV*vec4(uv,-1,1)).xyz;
  18. Thread: Edge detection

    by Spoops
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    Your mesh is composed of triangles or quads,...

    Your mesh is composed of triangles or quads, which are defined by vertices, and thus edges between those vertices. You could iterate over all polygons and deduce the lines to draw.
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    You mean == instead of = In your case the...

    You mean == instead of =
    In your case the condition will never be satisfied and you will operate on a buffer that does not exist.
  20. Thread: Edge detection

    by Spoops
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    I don't see why: you could generate the lines...

    I don't see why: you could generate the lines just after loading the mesh, since it is not view-dependent.
  21. Thread: Text rendering

    by Spoops
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    Freeglut uses legacy OpenGL, which is not...

    Freeglut uses legacy OpenGL, which is not available with any core profile. Either use modern rendering techniques or simply don't create a core context.
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    You have to do post-processing, i.e. rendering...

    You have to do post-processing, i.e. rendering your scene to a texture, then use that texture on a full screen quad with the desired effect in the fragment shader. What you called accessing fragments...
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    It looks like you want to use glMultiDrawArrays...

    It looks like you want to use glMultiDrawArrays to render parts of a vertex buffer without re-organizing the data, but it's bad practice. It's like calling 256 times glDrawArrays but with less driver...
  24. Don't load the identity matrix in your display...

    Don't load the identity matrix in your display function, as it will reset the orthographic projection if you don't resize the window.
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    OpenGL is hard to debug without tools, you should...

    OpenGL is hard to debug without tools, you should try to use gdb (for general programming, a must-have for not going crazy) and apitrace which logs all calls and enables you to see the OpenGL state...
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