Added the plasma sample to the README file.

Added a comment about loop unrolling to the plasma source.


git-svn-id: svn://svn.cc65.org/cc65/trunk@1016 b7a2c559-68d2-44c3-8de9-860c34a00d81

samples/plasma.c

@@ -112,6 +112,10 @@ static void doplasma (void)
     c2A += 2;
     c2B -= 3;
     for (ii = 0; ii < 25; ++ii) {
+	/* Unrolling the following loop will give a speed increase of
+	 * nearly 100% (~24fps), but it will also increase the code 
+	 * size a lot.
+	 */
         for (i = 0; i < 40; ++i, ++scrn) {
             *scrn = (xbuf[i] + ybuf[ii]);
         }