View Full Version : Help: Transparency

03-07-2010, 05:51 PM
You guys do some excellent maps and frequently have "bits" I'd love to use in my own. I know you can use magenta to give things a transparent background in Paint but I don't know the color code. I'm sure one of you does, help please?

03-07-2010, 06:24 PM
I think (using RGB) it's 255,0,255

03-07-2010, 06:30 PM
Thanks :) Appreciate the help.

03-07-2010, 11:24 PM
Well, that's the right code for magenta, and it's the shade I remember. But it didn't make the background transparent, just bright pink ><

Any more help available? Please?

03-08-2010, 02:16 AM
Are thinking of paint or visual studio? Googling got me this:


03-08-2010, 08:22 AM
I broke down and got a used copy of Paint Shop. Thanks anyhow, guys :)

03-08-2010, 10:59 AM
I'm sitting at a Mac right now, so I haven't access to Paint at the moment. However, I can give a couple of pointers regarding transparency. First, in order to have any transparency at all, you must be using a file format that permits it. Of the common formats usable on the web, gif and png both permit transparent pixels. Jpeg does not. bmp doesn't either, but it's not really any good for the web, anyway.

Now, gif and 8-bit png (png-8) use an "indexed" color palette, meaning that every color in your image is placed on a table stored with the file, and some of those colors can be designated as transparent if you wish. You can use a color drastically different than the rest of the image to make transparent, thus the magenta, but if you want the best results, you should use the color that you anticipate being used behind the image in order to avoid having oddly-colored halos around the image.

24-bit png uses four color channels: red, green, blue, and alpha. Alpha is the transparency channel. Each color channel is essentially a greyscale image, and in the alpha channel, the level of a pixel determines how transparent it is. 0 (black) is completely transparent. 1 (white) is completely opaque. This allows for smoother edges on transparent objects because the edges can be antialiased, becoming slightly transparent and allowing the background color to bleed through into the smooth edges, so you don't have to worry about the halos as much (more or less depending on how the image editor handles alphas over a colored background).

The concept of color channels is a bit difficult to wrap your head around at first, so if you don't "get" what I'm talking about, don't worry too much about it. Come back and read this again in a few months, after you've been working with digital images for a while, and it will probably make more sense.

03-08-2010, 11:03 AM
Ah, see, I didn't know all that. Thanks :) It explains alot of my difficulties and frustrations.

03-08-2010, 01:40 PM
With apps that have to edit images with transparency, showing what is transparent can be a bit tricky. You can use one color to substitute for the real transparent one but its very app dependent. I dont think that Paint can do it tho as someone has suggested you do sometimes see icon editors have special colors in the palette. With Paint Shop you can set a transparent color index and it will make that color invisible when viewed with something like a web browser. As said this is for 8 bit PNG and GIF. The 32 bit PNG can do transparent fades as well which is what we all use for tokens in maps.