A quick guide for Hi-res stuff, since 1.1 was released this method became obsolete, however, probably there are people still creating for 1.0 or lower. There was a tutorial by ExShadow iirc, but can't seem to find it, so I made one myself.
There are a couple of layering "tricks" that make easier coding hi-res stuff while using indexed images.
Let's start with this.
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As you can see, the edges of this image are antialiased (they're smoothed with transparent pixels to help them blend with whatever you put behind it), this is usual in hi-res stuff, normally to code this in mugen (indexed), one would have to remove the alpha pixels leaving sharp edges & reducing the quality, but using an image with brightness at max + substractive transparency can help to reduce the time spent cleaning the alpha pixels (that's if you don't know how to create a script to do it) and improves the overall look.
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So your layers should look like this:
This is the alpha that uses substractive transparency, it goes behind your sprite.
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This is your normal sprite that uses additive transparency.
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And in your def file lines should be like this:
[BG 0];-----------------------alpha with substractive trans.
type = normal
spriteno = 60, 1
layerno = 1
start = -800, 289
delta = 2, 2
trans = sub
[BG 0];----------------------your normal sprite with additive trans.
type = normal
spriteno = 60, 0
layerno = 1
start = -800, 289
delta = 2, 2
trans = add
This is the result:
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Since it's a foreground object let's say I want to add some defocus:
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Now you can notice a black edge around the barrel, this can be fixed by decreasing the brightness of the alpha OR adding another additive layer BEHIND the substractive one, like this:
[BG 0];-----------------------alpha with addalpha trans, 180,256 works fine most of the time.
type = normal
spriteno = 60, 1
layerno = 1
start = -800, 289
delta = 2, 2
trans = addalpha
alpha = 180,256
[BG 0];-----------------------alpha with substractive trans.
type = normal
spriteno = 60, 1
layerno = 1
start = -800, 289
delta = 2, 2
trans = sub
[BG 0];----------------------your normal sprite with additive trans.
type = normal
spriteno = 60, 0
layerno = 1
start = -800, 289
delta = 2, 2
trans = add
The result:
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The downside to this method is that if your stage has too many big layers you shouldn't abuse it too much, otherwise you can cause slow down on lower-end computers, with opengl is not a problem though.
This can be used to give more opacity to hi-res effects in characters as well, ever noticed how non-bright colors become way too transparent with add-transparency?
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There are a couple more things, but will post it later.