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I'm trying to draw a subregion of a texture in OpenGL by specifying the coordinates I want. What's happening though is that, depending on the size of the image, it seems there's a slight offset in the origin of where it selects the texture coordinates. The offset amount seems to be less than the size of a pixel & the output is is blurred combination of neighboring pixels. Here's an idea of what I'm describing. In this case I'd want to select the 6x5 green/white region but what OpenGL is rendering includes a slight pink tint to the top & left pixels. What the output would look like: I can fix it by adding an offset to the texture coordinates before passing them to glTexCoordPointer but the problem is that I have no way to calculate what the offset is and it seems different for different textures. Pseudocode: float uFactor = regionWidth / textureWidth; // For the example: 0.6f float vFactor = regionHeight / textureHeight; // For the example: 0.5f data[0].t[0] = 0.0f * uFactor; data[0].t[1] = 0.0f * vFactor; data[1].t[0] = 1.0f * uFactor; data[1].t[1] = 0.0f * vFactor; data[2].t[0] = 0.0f * uFactor; data[2].t[1] = 1.0f * vFactor; data[3].t[0] = 1.0f * uFactor; data[3].t[1] = 1.0f * vFactor; glPushMatrix(); // translate/scale/bind operations glTexCoordPointer(2, GL_FLOAT, 0, data[0].t);

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