Can hide the mouse cursor and make controls handling a little simpler

[GoogleCodeExporter]

Just a small suggestion for the tutorial:

If you call the following in your main routine (in the setup before rendering):

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glfwSetInputMode(window, GLFW_CURSOR, GLFW_CURSOR_DISABLED);
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The mouse cursor will be hidden, which is nicer than to have it sit in the 
middle of the screen. Then you would have to change the 
computeMatricesFromInputs() function in the controls.cpp file:

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void computeMatricesFromInputs() {
    // ...

    // Reset mouse position for next frame
    glfwSetCursorPos(window, 0, 0);  // note: 0, 0

    // Compute new orientation (note: -= not +=)
    horizontalAngle -= mouseSpeed * (float)xpos;
    verticalAngle   -= mouseSpeed * (float)ypos;

    // ...
}
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Note how the code becomes simpler. Hope this helps, and thanks for the 
tutorials! :)

Original issue reported on code.google.com by andrej.mitrovich on 3 Mar 2014 at 5:50