[SDL] Loading pure RLE ( not Bitmap ) Image...

[David Olofson]

On Thursday 16 June 2005 00.56, Dominique Louis wrote:
> I have some image data that is already RLE encoded, but contains no 
> Bitmap headers, so essentially raw RLE. Is there an easy way to load 
> this data using SDL?

RLE (Run-Length Encoding) is a vague term, and can be pretty much 
anything that's based on the general idea of encoding sequences of 
identical (or even similar) objects in some way, for speed and/or 
space.

That said, there is a (relatively) easy way:

	1. Create a surface (SDL_CreateRGBSurface()) with a fixed,
	   known pixel format; 24 bit RGB, 32 bit RGBA or whatever.

	2. Hack your own decoder that loads the file into a buffer
	   and decodes it into the 'pixels' array of the surface.

	3. Use SDL_ConvertSurface(), SDL_DisplayFormat() or
	   whatever you need, to convert the surface to a suitable
	   pixel format for your application - if you need to
	   convert it at all. (Usually not really necessary unless
	   speed is critical. SDL converts on-the-fly as needed.)


//David Olofson - Programmer, Composer, Open Source Advocate

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