Question on projecting from a Real Projector and stretching the viewport

Troubleshooting General Help
1

I would like to set up a real projector to project a JMonkey Screen onto a table. The Scene will just be a grid to start with. Eventually I want it to be and Dungeons and Dragons Player map. Is there a way I can set the viewport or something else to stretch in one axis? I.E. if the real projector is about 2 feet above the table pointing down about a 45% angle. the X axis would be fine , but the Y axis would be stretched very far across the table. So instead of 1’‘x1’’ boxes i would get 1’‘x3’’ boxes. I want to set the settings so that the boxes would be 1"x1" no mater where I have the real projector in relation to the table.

Thanks
-Greg

2

I think the term you are looking for is “keyhole” type of adjustment? ie: one edge of the screen is shorter than the opposite edge.

Your best bit will be to render your scene to a texture and then draw the texture on a quad oriented the same as the table. The bonus is that this is much easier to align, too.

Any straight stretching will fail because it won’t take perspective into account. The squares farther away from the projector would be stretched different than the near ones.