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Revelation60

OpenGL Creating an own glRotatef

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Hi, For my matrix library I made a rotate function based on the references I found of the glRotatef function. This is my implementation:
inline void Rotate(float angle, float x, float y, float z)
    {
		vector3f axis(x, y, z);
		axis.Normalize();

        matrix4f rot; // auto set to identity

		float b = angle;

		float c = cosf(b);
		float ac = 1.00f - c;
		float s = sinf(b);

		rot.m[0] = axis.x * axis.x * ac + c;
		rot.m[1] = axis.x * axis.y * ac + axis.z * s;
		rot.m[2] = axis.x * axis.z * ac - axis.y * s;

		rot.m[4] = axis.y * axis.x * ac - axis.z * s;
		rot.m[5] = axis.y * axis.y * ac + c;
		rot.m[6] = axis.y * axis.z * ac + axis.x * s;
		
		rot.m[8] = axis.z * axis.x * ac + axis.y * s;
		rot.m[9] = axis.z * axis.y * ac - axis.x * s;
		rot.m[10] = axis.z * axis.z * ac + c;


This should give the same result as:
glMatrixMode(GL_MODELVIEW);
        glPushMatrix();
        glLoadMatrixf(m);
        glRotatef(angle * 180 / 3.14, x,y,z);
        glGetFloatv(GL_MODELVIEW_MATRIX, rot2.m);
        glPopMatrix();


But it doesn't :| What am I doing wrong?

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All I can think of is that you got the major order wrong. So where m[1] in your program is the component first from the left at the top, it should be first from the top at the left. I would check, but I can't remember whether GL matrices are row-major or column-major, and it doesn't seem to mention in that Rotate reference.

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