Change animated apps to double-buffered visuals by default.
diff --git a/progs/samples/stretch.c b/progs/samples/stretch.c
index 3f610e7..9efa8e1 100644
--- a/progs/samples/stretch.c
+++ b/progs/samples/stretch.c
@@ -285,7 +285,7 @@
 {
     GLint i;
 
-    doubleBuffer = GL_FALSE;
+    doubleBuffer = GL_TRUE;
 
     for (i = 1; i < argc; i++) {
 	if (strcmp(argv[i], "-sb") == 0) {