From: Nick Bowler <nbowler@draconx.ca>
Date: Wed, 16 Nov 2022 05:16:29 +0000 (-0500)
Subject: x11: Improve redraw of empty spaces.
X-Git-Url: https://git.draconx.ca/gitweb/rrace.git/commitdiff_plain/a1b5bfc01e1a7ff2b6bf64a9367b87058162047c?hp=a1b5bfc01e1a7ff2b6bf64a9367b87058162047c

x11: Improve redraw of empty spaces.

When the game area is showing only the middle portion with the empty
border, we can clear this with 4 or fewer draw calls instead of 16.
Let's handle this as a special case in the tile drawing code.

Moreover, we don't need to draw anything in these spaces on expose
events, as the exposed areas are already filled with the background.
---