How to get Yaw, Pitch, and Roll from a Matrix?

Started by CyanPrime, May 23, 2011, 04:26:16

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CyanPrime

Is this correct? If now can you post what would be?

float yaw = (float) -(Math.tan(m.m10/m.m00));
        float pitch = (float) -(Math.tan((-m.m20)/(Math.sqrt(Math.pow(m.m21, 2) + Math.pow(m.m22, 2)))));
        float roll = (float) -(Math.tan(m.m21/m.m22));


Full source

import org.lwjgl.opengl.GL11;
import org.lwjgl.util.vector.Matrix3f;
import org.lwjgl.util.vector.Vector3f;

public class Camera {
     //3d vector to store the camera's position in
    Vector3f position = null;
    Vector3f lookAt = null;
    //the rotation around the Y axis of the camera
    float yaw = 0;

    //the rotation around the X axis of the camera
    float pitch = 0;

    //the rotation around the Z axis of the camera
    float roll = 0;

    public Camera(float x, float y, float z)
    {
        //instantiate position Vector3f to the x y z params.
        position = new Vector3f(x, y, z);
        lookAt = new Vector3f();
    }

    public void lookThrough()
    {
        Matrix3f m = new Matrix3f();



        Vector3f out = new Vector3f();
        Vector3f.sub(position, lookAt, out);
        out.normalise();
        //set forward vector
        m.m00 = out.x;
        m.m01 = out.y;
        m.m02 = out.z;

        //set right vector
        m.m10 = 1;
        m.m11 = 0;
        m.m12 = 0;

        //set up vector
        m.m20 = 0;
        m.m21 = 1;
        m.m22 = 0;

        yaw = (float) -(Math.tan(m.m10/m.m00));
        pitch = (float) -(Math.tan((-m.m20)/(Math.sqrt(Math.pow(m.m21, 2) + Math.pow(m.m22, 2)))));
        roll = (float) -(Math.tan(m.m21/m.m22));

        //roatate the pitch around the X axis
        GL11.glRotatef(pitch, 1.0f, 0.0f, 0.0f);
        //roatate the yaw around the Y axis
        GL11.glRotatef(yaw, 0.0f, 1.0f, 0.0f);
        //roatate the yaw around the Y axis
        GL11.glRotatef(roll, 0.0f, 0.0f, 1.0f);
        //translate to the position vector's location
        GL11.glTranslatef(position.x, position.y, position.z);
    }
}