demo worthy. Plenty more work could be done, but not terrible

src/util.cpp

@@ -41,4 +41,4 @@ glm::mat4 quat_to_mat4(glm::quat q) {
     return glm::mat4(col0, col1, col2, col3);
 }
 
-float randf() { return (float)rand() / (float)RAND_MAX; }
+float randf() { return (float)abs(rand()) / (float)RAND_MAX; }