From: Chris Pine <cpine@...>
Date: 2004-05-19T23:03:02+09:00
Subject: Re: Sprites in RUDL

On Wed, 19 May 2004 05:18:48 +0900, Linus Sellberg wrote:
>> What I want is (I guess), to restore just the areas where the
>> sprite moved from, so I guess I need to take a copy of what was
>> in that area before I draw the sprite.
>>
>
> Well, an idea that requires less work is to keep the whole
> background unmodified all the time, and just update the area around
> (and under for simplicities sake) the pac, all the time.

This works for small numbers of moving sprites, but for larger numbers it is best to simply blit the whole background.

Blits like this should be *fast*, though...

I don't normally do lower-level graphics work, but if you have slow blits, I *think* part of the problem could be conflicting formats in your buffers.  If you have an 8-bit palettized background buffer being blitted to a 16-bit drawing buffer, but your screen resolution is 24-bit, that's a lot of conversion going on.  I think.  Try making everything 32-bit and see if that speeds things up.

Chris