+PROJECT = project2
+IUSE = CLIPPING DEPTH_TEST SMOOTH_COLOR \
+ EXTRA_INLINE NDEBUG RASTER_STATS RENDER_PROGRESS RENDER_TIMER
+
+
+# BACKFACE_CULLING prevent drawing triangles that are not facing forward
+# CLIPPING turn on clipping (you really always want this)
+# DEPTH_TEST enable the z buffer for depth testing
+# EXPORT_BMP save scene as bitmap (enabled by default)
+# EXPORT_PPM save scene as a PPM file (also enabled by default)
+# EXTRA_INLINE allow the compiler to inline even more aggressively
+# LIGHTING turn the lights on (experimental)
+# NDEBUG disable assertions and other nonessential checks
+# PRE_NORMALS[=n] pre-compute mesh normals at scene-loading time;
+# set to 1 for per-face normals, 2 for averaged normals,
+# or 3 to also enable caching the computed normals
+# RASTER_STATS print triangle count and optimization savings at the end
+# RENDER_PROGRESS print progress while drawing the scene
+# RENDER_TIMER add a timer to see how long the renderer takes
+# SMOOTH_COLOR interpolate colors smoothly between triangle vertices