Hi all,

I am building a small radar type thing, so I can find where things are. To do this I use:

- I use the CameraNode.

- I get the target node’s position relative to the camera, by subtracting the world position of the camera from the world position of the node.

- I rotate it into the local space of the camera, by getting the world rotation of the camera node, converting it to a rotation matrix, taking the transpose of that matrix, and multiplying the vectors out.

- I then plot the z,x coordinates on a plane and draw a line of height y at that position.

The problem I have is that for some strange reason the x coordinate seems to be flipped. or maybe the y coordinate is flipped. I don’t know. it just seems to be in the opposite handedness space.

have I done something wrong?

try here:

// note: cn = camera node

Quaternion q = new Quaternion(cn.getWorldRotation());

Matrix3f r = new Matrix3f();

q.toRotationMatrix(r);

r.transposeLocal();

Vector3f v = new Vector3f(400,0,0);

v.subtractLocal(cn.getWorldTranslation());

r.mult(v,v);

v.normalizeLocal();

v.multLocal(400f);

System.out.println("["+v.x+","+v.y+","+v.z+"]");