Some Ideas for Doomsday (sorry if wrong subforum)
HeXen PlayStation have some interesting improvements among other 'degradations'
The First is Partially Lighted Sprites
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The Second is Bright maps
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If you wish to look into more hexen playstation screenshots go here
http://hexen-game.ru/forum/6-666-25333-16-1584274625
They have some odd diferences to PC DOS version, fun to look too.
Idea is to add Partial Light to Sprites and Bright maps for Doomsday.
The First is Partially Lighted Sprites


The Second is Bright maps

If you wish to look into more hexen playstation screenshots go here
http://hexen-game.ru/forum/6-666-25333-16-1584274625
They have some odd diferences to PC DOS version, fun to look too.
Idea is to add Partial Light to Sprites and Bright maps for Doomsday.
Comments
I'm not convinced that lighting sprites strictly based on sector lighting makes much sense. In a 3D renderer, sprites are billboards so they will turn around and as you move, some parts of them may move in and out of dark sectors, potentially resulting in a distracting visual artifact.
So sprite has some radius right?
And instead of partially lighted sprite.
Lets calculate how much in percentage sprite in dark sector and how much in light.
Blend them together (lerping).
So when sprite, lets call it monster, going from dark sector to light sector it will not change brightness instantly, but fade in and out of two values, that intersect this radius of current sprite (monster).
Some kind of another interpolation, for eye candy satisfaction