OpenGL Custom Locator always face camera Maya API

[Dilen Shah]

Hey guys,

I am trying to learn how to create a shape that always faces the camera. I have created before a locator which has its name facing the camera always but how can i do it with the whole shape itself?

Any ideas?

D.

[Serge Scherbakov]

Hi,

To achieve it, you can multiply locator transforms on M3dView.modelViewMatrix().inverse()

I use the following to keep my MPxManipulatorNode (circle) oriented on camera (partial copy/paste from draw() method) It's c# but on python workflow the same.

        public override void draw(M3dView view, MDagPath path, M3dView.DisplayStyle style, M3dView.DisplayStatus status)

        {

            .....

            MMatrix modelViewMatrix = new MMatrix();

            view.modelViewMatrix(modelViewMatrix);

            .....

      

            OpenGL.glLineWidth(3);

            OpenGL.glBegin(type);

            for (double i = 0; i < 2 * M_PI; i += M_PI / CIRCLE_SIDES_NUM)

            {

                MPoint circlePoint = new MPoint(Math.Cos(i) * radius, Math.Sin(i) * radius, 0.0);

                MVector circlePointVector = new MVector(circlePoint);

                circlePointVector = circlePointVector.multiply(modelViewMatrix.inverse);

                OpenGL.glVertex3d(circlePointVector.x + center.x, circlePointVector.y + center.y, circlePointVector.z + center.z);

            }

            OpenGL.glEnd();

         }

I hope this will help.

Best Regards,

Serge Scherbakov


среда, 22 января 2014 г., 13:55:14 UTC+4 пользователь Dilen Shah написал: