Fog rendering

[Pureon]

BETTER than AOE3's FOW

No way! I've got to see this for myself.

[fabio]

The new fog rendering looks great indeed!

I noticed a problem, however, at the bottom of Miletus (I am on 8885):

[Ykkrosh]

I just playtested with the new fog, and I think it actually looks BETTER than AOE3's FOW.

Hmm, I don't think that should be possible . It should be doing pretty much exactly what AoE3 does.

And you thought it would be hard to do.

It was (though not hugely) . I still don't really like doing graphics work, but I suppose I understand it a little better now.

I noticed a problem, however, at the bottom of Miletus (I am on 8885):

Yeah, our handling of map edges still isn't ideal. I could just add a big black vertical rectangle covering each side of the map from the water plane down to the bottom of the terrain, to quickly fix this bug, so I'll probably do that. (We've discussed better ways to handle edges but I don't want to bother with that yet.)

[Jeru]

*Rings bell*

Calling for pretty screenshots with the new fog for PR purposes.

[Rasunadon]

So it means from Alpha 2 or higher?

[feneur]

So it means from Alpha 2 or higher?

The new fog rendering is from Alpha 4 and higher, as in only in SVN at the moment.

[Ykkrosh]

I could just add a big black vertical rectangle covering each side of the map from the water plane down to the bottom of the terrain, to quickly fix this bug, so I'll probably do that.

Done that. (Actually made it a bit more complex - the solid black sides hang down from the terrain (or the water if it's higher), so you should never be able to see anything through the edge. With this it'd be easy to do AoM-style terrain where there's a visible rocky texture all around the outside of the map, but that doesn't make sense for circular maps and I think I prefer the fade-to-black-at-edge look.)

[fabio]

Done that.

Confirmed fixed (fast!).

It's nice to see some active development again, it seems that's after alpha4 it has slowed a bit.

[Kimball]

*Rings bell*

Calling for pretty screenshots with the new fog for PR purposes.

Let me know before this happens.

[Mythos_Ruler]

Problem with fog at edge--units disappear near edge.

[Ykkrosh]

r8887 fixes that, by making tiles near the edge impassable to all units. (Didn't seem worth re-autobuilding just for that, though.)

[janwas]

Very nice!

This is done by creating a bitmap with one pixel per map tile, then doing a single 5x5 box blur on it

May I suggest a better smoothing kernel, though? A box filter is really bad. Since you're already separating the kernel, we can get a cheap but decent integral approximation of a Gaussian via binomial filter. Given your 5 taps, the coefficients are 1,4,6,4,1, which sum up to 16 and therefore don't require conversion to floating-point nor division.

I agree about not going through gyrations to support 2 TMUs, and disabling shadows sounds like a good compromise.

[Ykkrosh]

Thanks, done.

[Pureon]

I can't see any difference, the fog still looks excellent.

[WhiteTreePaladin]

Probably the more significant (though more subtle) difference is when you have a narrow strip of fog

In the old one it'd be almost invisible

so enemy units could vanish into it and you wouldn't know why

That should be slightly less common now

[WhiteTreePaladin]

Seems that if you try to place a foundation in FoW, it will be highlighted in red. It stays red even when some units arrive in the area. Any movement of the foundation placeholder once the FoW is cleared by arriving units will remove the red. However, you can still build it even while it is red colored as long as it is not covered by the FoW. I think it should turn back to the normal color as soon as the FoW is cleared though.

[Ykkrosh]

That's a consequence of the placement preview not being recomputed until you move your mouse. I guess it should get recomputed every turn, which'd fix this. Fixed.

[Ykkrosh]

How should buildings on the edge of fog be rendered? (Especially when we have giant ones like the pyramids.)

If I remember correctly, the AoM/AoE3 approach is that the building pops into visibility once its central point is out of the fog, and maybe(?) it changes all the terrain directly under the building to be visible. An alternative is to do something like this (the building on the left) - apply the fog texture to the buildings, exactly like how it's applied to the terrain. Probably the building would always get rendered, initially in pure black (so you could only see it where its silhouette covers a visible area) and then gradually becoming fully lit as you approach it. (You won't be able to select the building, or see dynamic changes to it, if it's still in the fog - it'll only be interactive once it's at least partially in a visible region.)

I think that looks nicer, but I don't know if there's subtle gameplay/artistic problems with it. Are there other games that do something like this? If not, why not? (The implementation in our engine is tedious (since there's like a dozen different model-rendering modes - I've just hacked it into one for now) but not particularly complex, and it shouldn't affect performance significantly.)

[Mythos_Ruler]

The second way is definitely nicer. It probably wouldn't be too hard to switch back to the old "AOM" way if it turns out to be a problem, would it?

[janwas]

I too like the blending. It should be much less jarring than suddenly popping the whole building into

full visibility.

AoK was a software renderer, and they need to keep runtime decisions to an absolute minimum, so it may just have carried over to AoM/AoE3 out of habit. They also didn't have as much variation in building sizes.

I don't see any gameplay problems (maybe even less, because a combination of huge buildings and small visibility might mean the center of buildings are never exposed).

[feneur]

Looks good, and as long as it doesn't hurt performance I really think showing the building gradually would be a lot nicer.

Would the "color buildings black in FOW/SOD" make them look something like the units/buildings in this screeshot: http://www.wildfiregames.com/forum/index.p...pe=post&id=2573 (minus the distance fog)? In that case I'm not too fond of it =)

[Pureon]

I too believe the second way is a huge improvement over AOM /A0E3 unit visibility, it's much more realistic and caters for larger 3D models.

[Ykkrosh]

The second way is definitely nicer. It probably wouldn't be too hard to switch back to the old "AOM" way if it turns out to be a problem, would it?

It'd be kind of irritating to do the work for the new rendering approach and then switch back to the old way, but it'd be trivial to actually do the switch.

Would the "color buildings black in FOW/SOD" make them look something like the units/buildings in this screeshot: http://www.wildfiregames.com/forum/index.p...pe=post&id=2573 (minus the distance fog)? In that case I'm not too fond of it =)

Without the distance fog they'll just be black on black, so you wouldn't see them at all. If we added distance fog then we'd probably multiply the distance fog colour by the visibility fog texture so it'd still be black on black.

[feneur]

Without the distance fog they'll just be black on black, so you wouldn't see them at all. If we added distance fog then we'd probably multiply the distance fog colour by the visibility fog texture so it'd still be black on black.

Ah, that sounds good

[WhiteTreePaladin]

Just wanted to say I agree with the others; the gradual approach looks great.