This review is about a Terraria video game that is a 2D indie platform game where you can do about anything you’d like. You can fight monsters, build buildings, explore the terrain, gather resources and craft items and equipment.
We’ve recently had major performance issues while testing the game. Debug information has shown that it was the graphics that was taking from 60 and up to 300 milliseconds per second to redraw all nodes. One of the issues that was discovered in analysis is that terrain ISceneNode had automatic culling EAC_OFF:
Recall our previous post about stretched terrain bug in the game. Shader that fixed the problem gave although an unpleasant bug in the form of many black dots with newer graphic drivers. The black dots are usually a result of a NAN error (not a number) and normally related to bad geometry, a bad shader, light or camera.
Stretched textures on vertical triangles is one of a million possible bugs when texturing terrain with shaders. To fix it we need to recalculate texture coordinates in 3 projections: x, y and z.
