Camera control / Clipping Planes

Rhino Developer
1

I feel like I have a good grasp of controlling the camera settings, but I am a little stuck on one thing. I am working out the math to “simulate” depth of field calculations for a given lens; by simulate, I was going to use the near and far frustrum planes as the bounds of the depth of focus. It all seems pretty fine until I get ready to set those planes (after calculating them based on the current aperature, etc.)

I don’t see any relevant set method other than

(in Rhino.Display.RhinoViewPort)

    //
    // Summary:
    //     Sets optimal clipping planes to view objects in a world coordinate 3d bounding
    //     box.
    //
    // Parameters:
    //   box:
    //     The bounding box
    public void SetClippingPlanes(BoundingBox box);

This might be workable, but the fact that it is a world box makes me think its not so easy. If I could give it a box aligned to the camera, great. If its world and the camera is tilted, seems like a lot of extra maths. I have the planes calculated.

Assuming this is the only way…anybody have a tip on the math? Seems you need to make a world aligned bounding box with max diagonal that has endpoints on near/far planes.

2

slight update to this. Turned out the math for the clipping planes wasn’t so hard. But they don’t seem to have an effect. I am wondering a) do they have to be active somehow, and b)how does my display conduit affect this (my guess is sgnificantly!).

It appears that the
protected override void CalculateBoundingBox(Rhino.Display.CalculateBoundingBoxEventArgs eventArgs) overrides them.
Update:
Currently my solution is to have the display conduit store a list of the cameras I want to control clip planes on, and then update their clipping planes after I calc the bounding box. Seems to work, in that the clipping planes are correctly set. Would be helpful if there is any example of doing this more cleanly.

3

Still haven’t managed to actually get my clipping planes to work based on camera frustrum. Thought it might help with images.

test Persp.jpg1069×687 32.7 KB

The upper is the view from the camera shown in the lower. Shouldn’t the objects be clipped according to the two dotted rectangles?

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