Skybox doesn't work with extreme frustum values

[cmacisaac]

I have a perspective camera set up. The lens.far value is 2500 and the lens.near value is 1500. I did this in order to get a higher quality shadow map. The lens.fov is 12 as well. These are all fairly extreme values.

The problem is in SkyBox.as at line 133.

The code
var size : Number = camera.lens.far / Math.sqrt(2) * .5;
produces the number 883.8 which is well below the near clipping plane of 1500.

I modified the code as such
var size : Number = ((camera.lens.far - camera.lens.near) / 2) + camera.lens.near;
Which puts the skybox in the correct location, but the corners get cut off when the camera rotates around.

Not sure how to fix this exactly, but the skybox should always be visible on the background regardless of the clipping space.

[DerSchmale]

This seems to be related to the master branch. Does the problem still exist in dev?

[cmacisaac]

I believe so. I'm using the 4.1 Alpha code, if that matters.

[DerSchmale]

Fixed in dev by projecting skybox with a dedicated projection matrix

[alihm]

The problem still persists, My lens.far value is 40000 and I get clipped corners on 4.1.4, I don't have the problem on 4.0.9.

I tried fixing it by adding a slight change(* 0.9) in DefaultRenderer.as line 159:

var a:Number = (q.x_p.x + q.y_p.y + q.z_p.z + q.w_p.w)/(cx_q.x + cy_q.y + cz_q.z + cw_q.w) * 0.9;

[62316e]

Same on 4.1.6