twinklebear / arcball-cpp Goto Github PK

What I did:

I modified example.cpp as follows:

1. Changed the cube to a half cube, by cutting away z>0, or in another word all the z=1 coordinates, I made them 0. This makes the original center be exactly in the middle of the visible half-cube.
2. Changed the eye to (0,0,5)
3. Change the angle in the glm::perspective() from 65° to 8°.
4. Compile and run example
5. Place the mouse cursor in the center of the (half-)cube
6. Press mouse button and drag

What happened:

The moving of the cube is much faster than the moving of the mouse and the center of the cube quickly escapes from the mouse.

What I expect to happen:

Since center is at (0,0,0) and the center of the half cube is also at (0,0,0) I would expect that while panning the center of the cube will remain under the center of the mouse.

Comments:

I've been trying to solve this on my own, but I still haven't understood what exactly is wrong, however, is is bothering me that in your panning routine don't take into account the projection matrix.

If I were to solve this, I will make a pull request, but I would be more than pleased if you can solve this.

Thanks a lot for arc-ball!