Rendering Errors - Winter's Fury

[Rachael]

Tested with Intel HD 4600 and NVidia GeForce 860M.

When playing Winter's Fury, there are rendering errors all over the place in the sky on various levels. Attached is a screenshot of only one of these errors.

Screenshot_Doom_20160710_075439.png

The solid white areas represent no-draw areas (used r_clearbuffer 2 to make them more clear).

I don't know if the author had to deal with them originally and just left them in there, or if this is a regression on GZDoom's code base, or if it's specific to my hardware (on two different GPU's). Tested with the following versions: 2.1.1, 1.9.1, and 2.2pre-1799-g6f57c9c - on all 3, same result.

-noshader, -gl2, and -gl3 also net the same result on the 1799 devbuild.

[Graf Zahl]

I couldn't see these precise glitches, but that map puts some horizon lines on sloped sectors - which plain and simply is an unsupported feature in the GL renderer. With the thick fog I cannot see what happens here. Can you make a screenshot without fog (gl_fogmode 0) and activate the coordinate display?

[Rachael]

I am not sure if this is what you meant by coordinate display (idmypos) but here it is. I also went and traveled to the actual portal area to take that screenshot to show where the problem actually occurs.

Also it's not completely obvious where the glitch is until you do the r_clearbuffer - I set mine to "2" to make it white. If I set it to 0 you just see the good old fashioned Doom HOM effect.

[Rachael]

More on this bug: It's a mapping error. Setting "gl_no_skyclear" to false fixes it.