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viewMatrix.LookAt() returns a vector of positive NaN

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viewMatrix.LookAt() returns a vector of positive NaN
« on: May 02, 2021, 18:25:38 »
I have some code to calculate the view matrix, following code from LearnOpenGL. I'm only really using LWJGL and JOML.

This is my method to get the view matrix:
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public Matrix4f getViewMatrix() {
        Matrix4f viewMatrix = new Matrix4f();
        viewMatrix = viewMatrix.identity();
        /*direction = new Vector3f(Math.cos(Math.toRadians(yaw)) * Math.cos(Math.toRadians(pitch)), Math.sin(Math.toRadians(pitch)), Math.sin(Math.toRadians(yaw)) * Math.cos(Math.toRadians(pitch)));
         First do the rotation so camera rotates over its position
        viewMatrix.rotate((float)pitch, new Vector3f(1, 0, 0))
                .rotate((float)yaw, new Vector3f(0, 1, 0));
        Then do the translation*/
        viewMatrix.translate(-position.x, -position.y, -position.z);

        viewMatrix.lookAt(position, position.add(cameraFront) , cameraUp, viewMatrix);
        return viewMatrix;


And my function to update the vectors
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public void updateCameraVectors() {
        cameraFront.x = Math.cos(Math.toRadians(yaw)) * Math.cos(Math.toRadians(pitch));
        cameraFront.y = Math.sin(Math.toRadians(pitch));
        cameraFront.z = Math.sin(Math.toRadians(yaw)) * Math.cos(Math.toRadians(pitch));

        //cross product of camerafront and 0,1,0 stored in cameraRight
        cameraFront.cross(new Vector3f(0, 1, 0), cameraRight);

        //gets the cross product of camera right with camera front and stores it in cameraUp
        cameraRight.cross(cameraFront, cameraUp);

The problem I'm having is that when I do viewMatrix.lookAt(position, position.add(cameraFront) , cameraUp, viewMatrix), it's equal to NaN. I can't really tell what I'm doing wrong, any help would be appreciated.


Offline KaiHH

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Re: viewMatrix.LookAt() returns a vector of positive NaN
« Reply #1 on: May 02, 2021, 18:49:12 »
position.add(cameraFront) does not do what you think it does.
Please read: https://github.com/JOML-CI/JOML/wiki/Common-Pitfalls#methods-without-a-dest-parameter-modify-this-and-return-this
So, position itself is being modified and so the first and the second argument to the lookAt method will be the same then.

Re: viewMatrix.LookAt() returns a vector of positive NaN
« Reply #2 on: May 02, 2021, 19:08:25 »
Then I'm assuming that

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        viewMatrix.translate(-position.x, -position.y, -position.z);

        Vector3f temp = new Vector3f();
        position.add(cameraFront, temp);
        viewMatrix.lookAt(position, temp, cameraUp, viewMatrix);
        return viewMatrix;

would work? If so, I'm having some other problem that makes me unable to see my square, but whatever it is, I'm glad to have eliminated one thing.

edit: turns out my mouselook is just broken