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I implemented hotkeys to control my camera like A,S,D,W, etc

I need to implement a button that triggers the camera moving AROUND a certain point like the following:

http://i.imgur.com/S7zBh.png

I want the camera to rotate around a given point (or axis) in a circular motion. How do I go to implement that?

thanks!!!!!!!!!

OK so I’ve done the math for dummies and got a better understand of quaternions and how things work. However, I still don’t know whats the approach to take on rotating around the Z-Axis from the camera.

- how can I get the center of the scene I am looking at as I want to rotate around the center of the map or whatever scene I am seeing.

- the harder questions is how do I do it?

could it be something as simple as adding a quat or vect to the cam like:

cam.setLocation(cam.getLocation().add(x, y, z));

cam.setRotation(quat);

thanks

not sure I got you, can you provide an example?

 Quaternion qRot = cam.getRotation();
                    Quaternion rot = new Quaternion();
                    rot.fromAngleNormalAxis(5, Vector3f.UNIT_Z); // something like this??? that flips it over to the other side of the map
                    cam.setRotation(rot);

thanks

it doesn’t work :S I am sorry I’m still new at this.

is center a Vector3f(0,0,0) ??

I used camRot.lookAt(center.subtract(camPos)); but need to add another Vector3f to it as lookAt takes two vectors anyways my code is:

 else if (name.equals("moveAroundPositive") && keyPressed) {

                    System.out.println("Rotating camera around Z axis Positively");

                    // position must be on a circle around the Z axis
                    // Vector with radius length = 10
                    Vector3f camPos = new Vector3f(0,0,10);
                    Vector3f center = new Vector3f (0,0,0);

                    Quaternion camRot = new Quaternion();
                    Quaternion tempQuat = new Quaternion();

                    // create a quaternion based on the angles passed
                    // and multiplied by camPos
                    tempQuat.fromAngles(0,tpf,0).multLocal(camPos);
                    //tempQuat.fromAngles(0,rota,0).multLocal(camPos);

                    camRot.lookAt(center.subtract(camPos), camPos);
                    //camRot.lookAt(new Vector3f(0,0,0), new Vector3f(0,1,0));
                    //rota +=1;

                    cam.setLocation(camPos);
                    cam.setRotation(camRot);
                }

again, i’m sorry but although I have some expertise in java, I never played with graphics before, thanks for your help

well thats what I used (I had it there uncommented) and my center is (0,0,0) however it does go BELOW the object as if I am rotating around the x or Y axes.

as if I am rotating around the x or Y axes

in case you misunderstood me.

In other words, say the center is (0,0,0) and my object is at the center also, I want to rotate my camera AROUND it.

 if (name.equals("moveAroundPositive") && keyPressed) {
Vector3f center = new Vector3f (0,0,0);
Quaternion camRot = new Quaternion();
Quaternion tempQuat = new Quaternion();
tempQuat.fromAngles(0,rota,0).multLocal(camPos); //rota = 1 initially
camRot.lookAt(new Vector3f(0,0,0), new Vector3f(Vector3f.UNIT_Y));
rota +=1;
cam.setLocation(camPos);
cam.setRotation(camRot);
}

This won’t work as intended – it will rotate around the object but not even consistently.

Lol, do you still have the flyCam enabled?

flycam is off

and I tried camRot.lookAt(center.subtract(camPos), new Vector3f(Vector3f.UNIT_Y));

what will happen is that it will place the camera in a 2D view with a camPos distance :S