[graphics] tfrag3 renderer (#978)

* begin work

* work

* working objs

* exporting

* it works

* before some time of day fixes

* add time of day interp and also fix zbuffer

* some small blending fixes

* improve randomess

* clean up extraction and missing blend mode

* culling, time of day, more level fixes

* more cleanup

* cleanup memory usage

* windows fix

common/util/os.cpp

@@ -0,0 +1,17 @@
+#include "os.h"
+
+#ifdef __linux__
+
+#include <sys/resource.h>
+
+size_t get_peak_rss() {
+  rusage x;
+  getrusage(RUSAGE_SELF, &x);
+  return x.ru_maxrss * 1024;
+}
+
+#else
+size_t get_peak_rss() {
+  return 0;
+}
+#endif