→Language features: Error log, troubleshooting section
User defined functions are supported, and a wide variety of commonly used functions are provided built-in as well. This allows the graphics card manufacturer the ability to optimize these built-in functions at the hardware level if they are inclined to do so. Many of these functions are similar to those found in the math library of the C programming language such as <code>exp()</code> and <code>abs()</code> while others are specific to graphics programming such as <code>smoothstep()</code> and <code>texture2D()</code>.
== Shader types ==