Rotate cam position

Troubleshooting SDK
1

Hey everybody,

I’ve got a simple question (hope so) but i just can’t figure it out…

I want to rotate the cam around location x150, y150 & z150
Because of my class “linear algebra” I want to do it by updating a vector with sinus and cosinus.
I used this piece of code with an airplane which had to make corners and it worked perfectly.

But for some reason I can’t get it to work with the cam.

Some ideas?

[java]Vector3f newPos = new Vector3f(1,0,1);

    // change coörds according to new angle 
    newPos = new Vector3f(                  
        newPos.x * cos + newPos.z * -sin,   
        newPos.y,                           
        newPos.x * sin + newPos.z * cos     
    );                                      
                                            
    
    cam.setLocation(cam.getLocation().add(newPos));
    cam.lookAt(new Vector3f(150,150,150), cam.getLocation());[/java]
2

Perhaps meditate on what these parameters mean:
http://hub.jmonkeyengine.org/javadoc/com/jme3/renderer/Camera.html#lookAt(com.jme3.math.Vector3f,%20com.jme3.math.Vector3f)

To me it looks like you are just passing random stuff… I can’t even close to make the second parameter into an up vector and I don’t know enough about your coordinate system to know if the first is sensible at all.

3

Let me explain how the airplane works:

[java]
public pattern()
{
float cos = (float) Math.cos(Math.toRadians(0.0625f));
float sin = (float) Math.sin(Math.toRadians(0.0625f));

    airPlane = new AirPlane(startingPosition); // I create my airPlane (its a custom shape) and set it to the default position

    // this way i make a 90 degree rotation
    if(i <= 180)
            corner(0.5f,0.5f);


    airPlane.addTranslation(newPos); // i add the new position to the current position of the plane

}

private void corner(float rotX, float rotZ)
{
Vector3f newPos = new Vector3f(rotX,0,rotZ); // axis of rotation

    // change coörds according to new angle
    newPos = new Vector3f(
        newPos.x * cos + newPos.z * -sin,
        newPos.y,
        newPos.x * sin + newPos.z * cos
    );

}

[/java]

4

Well, I will say it clearer, this line is definitely wrong:
cam.lookAt(new Vector3f(150,150,150), cam.getLocation());

5

you were right, I’m sorry

I was looking for a problem in the rotation but in fact, the rotation was perfect, only the lookAt was wrong…

[java]cam.lookAt(cube.getCenter(), new Vector3f(0,1,0));[/java]

Thnx a lot!