Re: [pygame] stupid question

[Pete Shinners <pete@shinners.org>]

enrike wrote:
> how can i make the background of a surface transparent?.
> I know its probably stupid question but i cannot find who to do it.
The easiest way is if you save your images in a file format that 
supports transparency. Pygame can then load the image and use the same 
transparency.

There are two types of transparency in Pygame. "Colorkey" and "Alpha". 
Colorkey transparency is the easiest, and I recommend you start with 
that. This is the same transparency you use in graphics for the web. GIF 
and PNG are probably the most natural formats for this.

Colorkey transparency means a specific color in the image is not drawn 
when you blit. Have a look at the Pygame example programs. They load 
images from a BMP which has no colorkey information. The load_image 
function assumes the border is transparent, so it gets the color of 
pixel at the topleft corner and sets that as the image colorkey.

This is also covered in more detail in the Chimp Tutorial.
http://pygame.org/docs/tut/chimp/ChimpLineByLine.html