Enjay wrote:I want to make a sprite with varying transluceny by using the alpha chanel, what do I do?
Ok, first of all no image editor I can think of can do this properly in indexed mode (ie when working with a paletted image). Formats like PNG support 8 bit RGBA, but PS, PSP, GIMP, etc don't work like that. You have to be working in true color mode; convert the image to true color (called RGB in gimp).
[PS, PSP, GIMP, etc] have a concept of a background layer. They are treated weirdly. Look in layers dialog, duplicate that background layer and delete the original. Now you can start using alpha transparency...
Select-by-color, select "transparent" color, hit delete (try ctrl-x if that didnt work)
Get out the erase tool*, try it out. It should seem kind of "pressure sensitive".
Make a new layer, get out brush tool, pick fuzzy-edged brush, draw on transparent area.
etc...
When you are done if you must have paletted PNG, you can use a utility like
pngquant (or imagemagick) to convert 24 bit rgba png to 8 bit indexed rgba png.
edit - in reply to enjay's next comment to keep this from going too far off topic
- *
erase tool works very similarly in all three programs.
Here's another description. You can't draw transparency "subtractively" any other way that I know of, it just draws transparency over whatever's there with the brush, pencil, etc tools. Gotta use E.
[quote="Enjay"]I want to make a sprite with varying transluceny by using the alpha chanel, what do I do?[/quote]
Ok, first of all no image editor I can think of can do this properly in indexed mode (ie when working with a paletted image). Formats like PNG support 8 bit RGBA, but PS, PSP, GIMP, etc don't work like that. You have to be working in true color mode; convert the image to true color (called RGB in gimp).
[PS, PSP, GIMP, etc] have a concept of a background layer. They are treated weirdly. Look in layers dialog, duplicate that background layer and delete the original. Now you can start using alpha transparency...
Select-by-color, select "transparent" color, hit delete (try ctrl-x if that didnt work)
Get out the erase tool*, try it out. It should seem kind of "pressure sensitive".
Make a new layer, get out brush tool, pick fuzzy-edged brush, draw on transparent area.
etc...
When you are done if you must have paletted PNG, you can use a utility like [url=http://www.libpng.org/pub/png/apps/pngquant.html]pngquant[/url] (or imagemagick) to convert 24 bit rgba png to 8 bit indexed rgba png.
edit - in reply to enjay's next comment to keep this from going too far off topic ;) - * [url=http://www.linuxtopia.org/online_books/graphics_tools/gimp_user_manual/en/gimp-tool-eraser.html]erase tool[/url] works very similarly in all three programs. [url=http://www.extropia.com/tutorials/photoshop/eraser_tool.html]Here[/url]'s another description. You can't draw transparency "subtractively" any other way that I know of, it just draws transparency over whatever's there with the brush, pencil, etc tools. Gotta use E.