Minor portal glitches

[Major Cooke]

Using this wad.

So I was standing right at the edge of a portal line when testing Arookas' wad out and I noticed when I changed my resolution, the portals stopped rendering. I had to restart to fix it.

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And then I discovered the player can still be rendered a little bit:
[spoiler][/spoiler]

But when standing back far enough, it's black.
[spoiler][/spoiler]

On rare occasions there's the flicker of something happening in front of the screen.
[spoiler][/spoiler]

Turns out it's you. That's the doomguy.
[spoiler][/spoiler]

[Graf Zahl]

I was unable to reproduce the resolution change issue.
The rest come from how this map is set up. This special case of mixing wall with flat portals seems to create problems with the logic that calculates portal shapes for clipping (as in looking from area B into different parts of area A in the same direction). I'll have to investigate a bit further if this is fixable.

[Graf Zahl]

fixed the issue in the second picture. The red thing is the wall behind the portal. This was caused by incomplete clearing of the clipper.

The occasional display of the player sprite requires some fundamental work on how the engine tracks portals. This needs to be done in ZDoom first.

[Graf Zahl]

For now I patched this problem so that the most glaring effects are dealt with, but after doing some analysis it became clear that a proper fix that catches all cases would cost too much performance (as in checking a subsector against every single camera-facing line in the portal - this is precisely the stuff that was causing performance issues when I wrote my experimental Build-style renderer a few years back.)

[Major Cooke]

Fair enough. Thanks!

[Major Cooke]

I was unable to reproduce the resolution change issue.

Oh right, I was in fullscreen mode and I changed to windowed.

[Graf Zahl]

That also did not glitch for me.

[Major Cooke]

Did you position yourself to the point where you could see the doom marine? That's how I got it to glitch.