Buggy Stacked/3d Sectors

[jensenn]

I mostly just want to know if this is won't fix or an issue I should bother writing a detailed bug report on. I can upload wads IDK how to upload and link them here (what site way the mods prefer I do some forums are really picky that's why I ask) also I could make a demo/ video to make pin pointing anything easier.

[Professor Hastig]

How are we supposed to answer your question without seeing your map?

[axredneck]

You can use https://www.dropbox.com/ to upload files.

[jensenn]

Professor Hastig wrote:
> How are we supposed to answer your question without seeing your map?
https://www.dropbox.com/scl/fi/p0wpc1lj ... 7nedv&dl=0

[Rachael]

The sectors are correct, but the renderer is broken. Software render mode cannot do sector portals well, it's always been a problem and nobody has ever wanted to fix it. So this will stay broken indefinitely. The only fix is to use the hardware renderer, or don't use sector portals.

Also - it is not necessary to package the entirety of Freedoom with your map (and not recommended, either, since Freedoom can publish updates at any time, and it also may cause conflicts with resources a player may have loaded).

[Guest]

Rachael wrote:
> The sectors are correct, but the renderer is broken. Software render mode
> cannot do sector portals well, it's always been a problem and nobody has
> ever wanted to fix it. So this will stay broken indefinitely. The only fix
> is to use the hardware renderer, or don't use sector portals.
>
> Also - it is not necessary to package the entirety of Freedoom with your
> map (and not recommended, either, since Freedoom can publish updates at any
> time, and it also may cause conflicts with resources a player may have
> loaded).

OK I thought so. I was hoping to have an example to show what will and won't work in software mode any tips for that or is it impossible? Is there a version where it's known to be less buggy? What should I do to make my map run standalone without the freedoom issue your describing, I'm just not aware of a better way to do it I've only been mapping for doom for 1.5 yearsish?

[jensenn]

Guest wrote:
> Rachael wrote:
> > The sectors are correct, but the renderer is broken. Software render mode
> > cannot do sector portals well, it's always been a problem and nobody has
> > ever wanted to fix it. So this will stay broken indefinitely. The only fix
> > is to use the hardware renderer, or don't use sector portals.
> >
> > Also - it is not necessary to package the entirety of Freedoom with your
> > map (and not recommended, either, since Freedoom can publish updates at any
> > time, and it also may cause conflicts with resources a player may have
> > loaded).
>
> OK I thought so. I was hoping to have an example to show what will and won't work in
> software mode any tips for that or is it impossible? Is there a version where it's
> known to be less buggy? What should I do to make my map run standalone without the
> freedoom issue your describing, I'm just not aware of a better way to do it I've only
> been mapping for doom for 1.5 yearsish?
Was me just didn't realize I was logged out.

[jensenn]

Rachael wrote:
> The sectors are correct, but the renderer is broken. Software render mode
> cannot do sector portals well, it's always been a problem and nobody has
> ever wanted to fix it. So this will stay broken indefinitely. The only fix
> is to use the hardware renderer, or don't use sector portals.
>
> Also - it is not necessary to package the entirety of Freedoom with your
> map (and not recommended, either, since Freedoom can publish updates at any
> time, and it also may cause conflicts with resources a player may have
> loaded).
Can you explain what is known to be wrong with the software portion? I might have a crack at fixing the bug. I just don't want to waste time figuring out whats already know for a starting point. I'm willing to try to debug in renderdoc some has anyone already done that and brought it up in dev discussions?

[Rachael]

The problem with the software renderer sector portals is it does not clip at the line's viewpoint but rather the viewer's viewpoint, meaning things that are near the player on the other side of the portal will be more visible through the portal than what is supposed to actually appear.

[jensenn]

The problem with the software renderer sector portals is it does not clip at the line's viewpoint but rather the viewer's viewpoint, meaning things that are near the player on the other side of the portal will be more visible through the portal than what is supposed to actually appear.

So it draws it all from one view rather then two need for correct perspective drawing? is it unable to do two or was it never added? I might give that a crack.

[Graf Zahl]

It was never added. The software renderer's stacked sectors were a quickly abandoned attempt from more than 15 years ago, and since then nobody ever worked on it again.

[Rachael]

So it draws it all from one view rather then two need for correct perspective drawing? is it unable to do two or was it never added? I might give that a crack.

What it needs is to not allow lines that are between the view sector and the player to be drawn, at all.

Let's say the o> is the player here, facing east, and here's the top part of the stacked sector portal, and the portal is drawn in brackets [ ]:

Code: Select all

| o>       [ ]

Now here's the bottom part, with walls drawn as |:

Code: Select all

|     |    [ ]

As you can see, if we were to put those directly on top of each other, the player would appear behind the line that is on the bottom side. That causes that line to occlude everything in front of it, manifesting as the rendering glitch you see.

This and a hundreds of other weird glitches are reasons why the software renderer ultimately ended up abandoned over time. It can handle basic vanilla Doom maps just fine without issue - but anything more advanced than that, it usually has problems.

[Graf Zahl]

Handling that properly in the hardware renderer was not easy, it requires quite a bit of thinking out of the box. But due to the software renderer's messy state back in the day (before dpJudas refactored it it depended on a convoluted set of global variables that were hard to track down) I found no way to make this info work for software.

That's also not the only problem here. The software renderer's portal code cannot handle two sided walls with height differences well.