diff -r bf17f9f84c91 -r e6567b740c5e src/raytracer.cc
--- a/src/raytracer.cc	Thu Nov 22 17:53:34 2007 +0100
+++ b/src/raytracer.cc	Thu Nov 22 18:10:10 2007 +0100
@@ -230,7 +230,7 @@
 	vy = starty;
 
 #ifdef PTHREADS
-	int num_threads = 2;
+	int num_threads = 4;
 	printf("* pthreads enabled, using %d threads\n", num_threads);
 	pthread_t threads[num_threads];
 	for (int t = 0; t < num_threads; t++)