Simulink 3D Animation: how to compute the projection matrix associated with the camera view in a virtual reality world?

I am using Simulink 3D Animation to model a virtual reality environment.

In MATLAB, how do I calculate the projection of the world in the same way as it is rendered on the screen?

Answer 1

[MathWorks Support Team]

We will use the "Membrane" example for Simulink 3D Animation:

https://www.mathworks.com/help/sl3d/create-a-vrworld-object-to-represent-a-virtual-world.html

You can get the position and direction of the camera using the following code example:

>> wh = vrworld('membrane.wrl');
>> open(wh);
>> view(wh);
>> fig = get(wh, 'Figures');
>> dir = get(fig, 'CameraDirection');
>> pos = get(fig, 'CameraPosition');

You may need the Field Of View (FOV) of the camera.

First, get the name of the currently used viewpoint:

>> get(fig, 'Viewpoint')

If there is a viewpoint, get the FOV of each viewpoint:

>> vp = get(wh, 'Viewpoints');
>> getfield(vp, 'fieldOfView')

If there is no viewpoint, the FOV is set to the default value specified by the VRML Standard: 0.785398 radians (45 degrees).

Please refer to the following link for more information on the VRML standard:

https://www.web3d.org/documents/specifications/14772/V2.0/part1/nodesRef.html#Viewpoint