From: Lauri K. <ca...@gm...> - 2013-09-13 15:51:34
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Hi, As you know, fog was removed months ago from cluttering all shaders, to be put into a post-process effect. It's now implemented, with additional flexibility over fixed-function fog (height tunables, for example for subsea, or for some mountainous level [1]). Mansion is looking very fine now. However lighthouse shows the weak point: a PP effect cannot distinguish a transparent mesh against the sky from the sky. Sky obviously shouldn't get foggy. @samuncle: This should be taken into account in level design - trees visible against the sky (in foggy levels) should preferably be solid, ie use alpha_ref transparency. - Lauri [1] http://udn.epicgames.com/Three/rsrc/Three/HeightFog/ExponHeightFog.jpg |
From: Lionel F. <fu...@gm...> - 2013-09-14 22:26:25
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To me, the only advantage of doing fog in a post-process is to reduce the number of pixels treated (as would happen with a Z-prepass). Being able to tune the formula for how height influences fog can be done during lighting as well, but without the weakness you mention, so I don't think having it as a post-process is the best way to go. To me the drawbacks of having it in the lighting pass are: - need a #include system (which we don't have for now) to avoid code duplication - number of shader combinations (not a problem for STK at the moment). So I suggest we keep going with post-process for now but would benefit from having it in the lighting pass later on. Except if the limitation for transparent objects ends up not being too much of a burden for the artists... 2013/9/13 Lauri Kasanen <ca...@gm...> > Hi, > > As you know, fog was removed months ago from cluttering all shaders, to > be put into a post-process effect. It's now implemented, with > additional flexibility over fixed-function fog (height tunables, for > example for subsea, or for some mountainous level [1]). > > Mansion is looking very fine now. However lighthouse shows the weak > point: a PP effect cannot distinguish a transparent mesh against the > sky from the sky. Sky obviously shouldn't get foggy. > > @samuncle: > > This should be taken into account in level design - trees visible > against the sky (in foggy levels) should preferably be solid, ie use > alpha_ref transparency. > > - Lauri > > [1] > http://udn.epicgames.com/Three/rsrc/Three/HeightFog/ExponHeightFog.jpg > > > ------------------------------------------------------------------------------ > How ServiceNow helps IT people transform IT departments: > 1. Consolidate legacy IT systems to a single system of record for IT > 2. Standardize and globalize service processes across IT > 3. Implement zero-touch automation to replace manual, redundant tasks > http://pubads.g.doubleclick.net/gampad/clk?id=51271111&iu=/4140/ostg.clktrk > _______________________________________________ > Supertuxkart-devel mailing list > Sup...@li... > https://lists.sourceforge.net/lists/listinfo/supertuxkart-devel > |
From: Lauri K. <ca...@gm...> - 2013-09-15 05:47:58
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On Sun, 15 Sep 2013 00:25:57 +0200 Lionel Fuentes <fu...@gm...> wrote: > To me, the only advantage of doing fog in a post-process is to reduce the > number of pixels treated (as would happen with a Z-prepass). No, it's mainly for shader complexity. Practically _every_ shader had duplicated fog logic, and it was different in some, due to obvious reasons of someone only changing some. > Being able to tune the formula for how height influences fog can be done > during lighting as well, but without the weakness you mention, so I don't > think having it as a post-process is the best way to go. It would have the exact same weakness, as transparents aren't lit, only solids are. Lights cannot separate sky from transparents either. > So I suggest we keep going with post-process for now but would benefit from > having it in the lighting pass later on. Except if the limitation for > transparent objects ends up not being too much of a burden for the > artists... As it would have the same limitation in lighting pass too, I don't see how it would improve anything? - Lauri |
From: Lionel F. <fu...@gm...> - 2013-09-15 06:42:57
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Transparent objects aren't lit? So they don't receive shadows too, do they? That's weird/surprising... In that particular case, that's right, post-process would be the best choice. 2013/9/15 Lauri Kasanen <ca...@gm...> > On Sun, 15 Sep 2013 00:25:57 +0200 > Lionel Fuentes <fu...@gm...> wrote: > > > To me, the only advantage of doing fog in a post-process is to reduce the > > number of pixels treated (as would happen with a Z-prepass). > > No, it's mainly for shader complexity. > Practically _every_ shader had duplicated fog logic, and it was > different in some, due to obvious reasons of someone only changing some. > > > Being able to tune the formula for how height influences fog can be done > > during lighting as well, but without the weakness you mention, so I don't > > think having it as a post-process is the best way to go. > > It would have the exact same weakness, as transparents aren't lit, only > solids are. Lights cannot separate sky from transparents either. > > > So I suggest we keep going with post-process for now but would benefit > from > > having it in the lighting pass later on. Except if the limitation for > > transparent objects ends up not being too much of a burden for the > > artists... > > As it would have the same limitation in lighting pass too, I don't see > how it would improve anything? > > - Lauri > |
From: <sam...@gm...> - 2013-09-15 07:26:56
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Cand for new tracks: 1) Alpha testing will be used for vegetation 2) effects like glowing halo/etc will be done with forced bloom instead billboard. 3) I will try to restraint the alpha blending only for Windows/waterfall/etc 4) the bug that I reported only occur in mansion. I don't know why. Maybe it's related to additive transparency and billboard Le 15 sept. 2013 08:43, "Lionel Fuentes" <fu...@gm...> a écrit : > Transparent objects aren't lit? So they don't receive shadows too, do > they? That's weird/surprising... > In that particular case, that's right, post-process would be the best > choice. > > > 2013/9/15 Lauri Kasanen <ca...@gm...> > >> On Sun, 15 Sep 2013 00:25:57 +0200 >> Lionel Fuentes <fu...@gm...> wrote: >> >> > To me, the only advantage of doing fog in a post-process is to reduce >> the >> > number of pixels treated (as would happen with a Z-prepass). >> >> No, it's mainly for shader complexity. >> Practically _every_ shader had duplicated fog logic, and it was >> different in some, due to obvious reasons of someone only changing some. >> >> > Being able to tune the formula for how height influences fog can be done >> > during lighting as well, but without the weakness you mention, so I >> don't >> > think having it as a post-process is the best way to go. >> >> It would have the exact same weakness, as transparents aren't lit, only >> solids are. Lights cannot separate sky from transparents either. >> >> > So I suggest we keep going with post-process for now but would benefit >> from >> > having it in the lighting pass later on. Except if the limitation for >> > transparent objects ends up not being too much of a burden for the >> > artists... >> >> As it would have the same limitation in lighting pass too, I don't see >> how it would improve anything? >> >> - Lauri >> > > > > ------------------------------------------------------------------------------ > LIMITED TIME SALE - Full Year of Microsoft Training For Just $49.99! > 1,500+ hours of tutorials including VisualStudio 2012, Windows 8, > SharePoint > 2013, SQL 2012, MVC 4, more. BEST VALUE: New Multi-Library Power Pack > includes > Mobile, Cloud, Java, and UX Design. Lowest price ever! Ends 9/22/13. > http://pubads.g.doubleclick.net/gampad/clk?id=64545871&iu=/4140/ostg.clktrk > _______________________________________________ > Supertuxkart-devel mailing list > Sup...@li... > https://lists.sourceforge.net/lists/listinfo/supertuxkart-devel > > |
From: Lauri K. <ca...@gm...> - 2013-09-15 11:38:33
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On Sun, 15 Sep 2013 08:42:25 +0200 Lionel Fuentes <fu...@gm...> wrote: > Transparent objects aren't lit? So they don't receive shadows too, do they? Yes, that's correct. We don't currently have layered depth, nor the forward (expensive) way of looping for each transparent item. The current levels mainly use transparent parts for glowing things (lanterns, neon billboards), windows, and water, all parts that shouldn't be lit nor receive shadows. (water has special handling for the sun though, for the specular) Most of the vegetation is also better off with alpha testing, as their textures have hard-line separation, not a feathered/soft one. - Lauri |