GraphicsGale has been a very good tool in terms of my stage making ability. As it has helped me very well on making any color that I choose, a transparent color. So it would appear to do its job properly in mugen.
To make sure that it does the job, you will need the following things:
GraphicsGale (of course the free version. No need to get the paid version, when the free version can do the job)
http://www.humanbalance.net/gale/us/Any image editing tool you have on hand, that can save images in .png and .pcx format
whatever sprites you are using in .png format. So you can convert them to .pcx later.
Before I start, I will admit that not everyone likes using GraphicsGale. And some may not appreciate it's real potential. But this is the tool I've come to use, when it came to getting the proper transparency for each sprite used for my stages. Layer or otherwise.
Let's get started
Once you have the image you need in .png format (hopefully cut and sized to your liking already, with a proper background color that you plan on using. I hope it's magenta at least), go ahead an open GraphicsGale, and load your image into it (you can drag & drop images into it as well if you want, to save time). Your image should look like the following below. For
Make sure you have that palette sub-window open. You'll need it.
As stated, hopefully you would have picked magenta, or hot pink. As they are better colors for transparency. Despite
ANY color can be used as a transparent color layer (Magenta is highly recommended). For this tutorial, I'm using what came with the image.
Once you have your image loaded, you will need to click on "
All frames" then click on "
Color Depth", as seen here in the image below.
You will then be brought to the "Color Depth" window. As seen below.
You are only going to use this window two times per however many images you have, that you want a transparent color. By default, .png images are mostly saved in 8bit (8bpp-256 colors). You want to change that from 8bit, to 16bit, then pres "
OK". This is where that palette sub-window comes into play, from the first image. Changing it from 8bit to 16bit, initially does nothing, but give more colors to the palette available...yet.
Once you have done that, you want to go back into the Color Depth,
and switch it from 16bit, back to 8bit, and press "
OK". The palette sub-window will change, and only contain the colors of the image you loaded, as seen below.
You will now see just only the colors for that image. As well as what RGB settings for said color, if you scroll the mouse over each one. NOW the palette sub-window comes into play here. If you notice directly under it, you see the foreground & background color being two different shades (one flesh and one off-black respectfully). It is exactly that. what YOU want to do, is get that all green to be just that, your background color (or whatever color you have on the image, that you want it to be).
To make the color around the image your main transparent color, first you left click over the color you want as the "foreground transparent color", then you right click over that same color. You will notice the one color on the palette now has a highlighted white box, and a line crossing it. This means it is now your actual transparent color that you are going to use.
As a Protip: Make sure that said color you want as a transparent color is the
FIRST color in the palette. Meaning, it needs to be in the far upper left square of the palette grid. Otherwise known as the first color in the image.
To save it, just click the Save icon at the top menu (located under view), and proceed to just use whatever image editing tool that allows you to save .png images in .pcx format. This way, you don't have to do any further editing, just to make it transparent. As that information is saved within the colors, upon saving it into a new format.
The work is tideous, but well worth it in the end. Doing it this way, has aided me in getting colors to be right for stage creation. But it can be used with other methods. This method may not appeal to some, and there might be other, more simpler ways of handling it. BUT...this is the way I've learned on my own, how to do. And the results show itself in my stages.
I hope this helps to some degree.
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