demos: Changed cube per Alexandre Bacquart--2FPS with prints/frame.
diff --git a/demos/cube.c b/demos/cube.c
index 680e424..c76bb9f 100644
--- a/demos/cube.c
+++ b/demos/cube.c
@@ -30,6 +30,7 @@
 #include <signal.h>
 #ifdef __linux__
 #include <X11/Xutil.h>
+#include <unistd.h>
 #endif
 
 #ifdef _WIN32
@@ -779,6 +780,10 @@
         assert(!err);
     }
 
+static unsigned frameCount = 0;
+printf("frame %u\n", ++frameCount);
+usleep(500000);
+
     err = vkQueueWaitIdle(demo->queue);
     assert(err == VK_SUCCESS);
 
@@ -2982,7 +2987,11 @@
     demo->width = 500;
     demo->height = 500;
 
+#ifdef OLD_CODE
     demo->spin_angle = 0.01f;
+#else  // OLD_CODE
+    demo->spin_angle = 2.f;
+#endif // OLD_CODE
     demo->spin_increment = 0.01f;
     demo->pause = false;