nanogui: Re: Qusetion abuot Nano-X alpha blending
Subject:
Re: [nanogui] Re: Qusetion abuot Nano-X alpha blending
From:
Alex Holden ####@####.####
Date:
11 Jul 2005 07:42:02 +0100
Message-Id: <54635FE8-BB4F-45B5-BB97-FB6FBC9A52A6@linuxhacker.org>
On 10 Jul 2005, at 22:18, Greg Haerr wrote:
> Why introduce a new drawing type, why not have any pixmap
> serve as a potential alpha channel? In this way things are more
> general, and special code doesn't have to be written for
> alpha channel handling.
The main reason I did it like that was to save RAM at the expense of
a few K of extra code (most of it in drivers/alpha1.c). Pixmaps are
often 24bpp whereas alpha channels are always 8bpp. It also
simplifies dealing with them because alpha channels are inherently
always 8bpp grayscale whereas pixmaps are usually colour and the
format and depth can vary depending on the screen type.
--
------------ Alex Holden - http://www.alexholden.net/ ------------
If it doesn't work, you're not hitting it with a big enough hammer