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OpenGL in Java, Manual creatation of gluLookAt matrix


OpenGL uses column-major matrices. You appear to be filling your matrix row-by-row, this would actually work in Direct3D (row-major) FYI.

The simplest solution would be to call mLookatMx.transpose (...) (if you were using a proper matrix class); this would flip the rows and columns for you.

However, since you are using a plain old FloatBuffer, you need to put (...) the contents of your matrix one column at a time instead of one row at a time.

By the way, at its core OpenGL always uses matrices for transformations. Those Euler angle and quaternion helper utilities really just create transformation matrices for OpenGL. You can implement non-matrix based transformations in vertex shaders, but that is more advanced than you should be thinking right now :)


Categories : Java

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