# HG changeset patch
# User Matti Hamalainen <ccr@tnsp.org>
# Date 1274204827 -10800
# Node ID e5049100f6ac92e1ec3d6667faaf5c1b319d31c3
# Parent  18e14722f58a292d97206ef76e18228d238f298f
Optimize rasterization a bit.

diff -r 18e14722f58a -r e5049100f6ac pwplib/sdl.c
--- a/pwplib/sdl.c	Tue May 18 20:32:38 2010 +0300
+++ b/pwplib/sdl.c	Tue May 18 20:47:07 2010 +0300
@@ -43,18 +43,23 @@
 
     for (y = pwplib.videobuf.height; y; y--)
     {
-        int y2;
-        for (y2 = 4; y2; y2--)
+        int i;
+        Uint8 *dsrc = dst;
+        Uint32 *d = (Uint32 *)dst;
+        Uint8 *s = src;
+
+        for (i = pwplib.videobuf.width; i; i--)
+            *d++ = pwp_SDL.lookup[*s++];
+
+        dst += pwp_SDL.screen->pitch;
+
+        /* Optimization: memcpy the rasterized line 3 times below it */
+        for (i = 3; i; i--)
         {
-            int x;
-            Uint32 *d = (Uint32 *)dst;
-            Uint8 *s = src;
-
-            for (x = pwplib.videobuf.width; x; x--)
-                *d++ = pwp_SDL.lookup[*s++];
-            
+            memcpy(dst, dsrc, pwp_SDL.screen->pitch);
             dst += pwp_SDL.screen->pitch;
         }
+
         src += pwplib.videobuf.width;
     }