Sky Polygons when using Orthogonal Camera

Started by PabloMack, February 21, 2015, 11:52:25 AM

Previous topic - Next topic

PabloMack

I am using the Orthographic Camera as a way to create a map of a terrain. This is a map for workers to use to plan and select virtual shooting locations for the scenes in a movie. I started out with a square area 16km on side and went to 32km because of the concern that the end of the instantiated vegetation might become visible from an aerial shot. Finally I went to an area 64km on a side. This is where I started to see some unwanted artifacts. As you can see, the light blue polygons only appear around the edges and aren't visible in the 32km middle block where all of the action is to take place. I suspect that the cause of the problem stems from the fact that the orthogonal projection is linear while the surface of the Earth is not. I would expect the curvature of the Earth to play a role in getting some deformation in the image and even clouds toward the edges because I expect that the Y position where I put the camera is not a true altitude along a sphere enclosing the Earth but a plane that projects out into space. Still, I am not starting to see clouds but I am getting these large polygons that shouldn't be there. I tried turning off the atmosphere and clouds but the polygons just got black instead of light blue so I am convinced that the problem has something to do with the presence of the sky.

[attach=1]

At present, this is not a serious problem for me as the map will never appear in the production itself but is only a tool for planning the shots. I don't expect the polys to show up in renders from perspective cameras used to produce the movie. Furthermore, the unwanted polys don't seem to be in the central area of interest. This image was generated with the latest release.

Matt

What are the coordinates of your camera?

Matt
Just because milk is white doesn't mean that clouds are made of milk.

Dune

What if you temporarily use a flat earth or increased in diameter?

PabloMack

#3
Quote from: Matt on February 22, 2015, 12:38:21 AMWhat are the coordinates of your camera? Matt

[attach=1][attach=2]

The original render was at 4096 X 4096 (then reduced to save storage before posting) but I did it again at 1024 X 1024 and I get the same blue polygons. The result is the same even when the camera is at [0,1000,0] centered on the origin looking down.

Matt

I don't know why it's happening, but raising the Y position of the camera should solve it. Try 64000.

Matt
Just because milk is white doesn't mean that clouds are made of milk.