GLSL part II

• Page 50 has a list of the operators.
• 
• Flow control.
  • if (be) { statement; } else { statement;}
    • The else clause is optional
    • As are the {}
  • switch (int_value) { case : statements; break; default: statements}
    • No statements before the first case.
  • for, while and do while as in C++
  • break, continue, return
  • discard : fragment shader only, exit with a message to disregard results.
• Functions:
  • There are a large number of predefined functions
  • Look at a appendix c
  • Many math functions, sin, sinh, pow, log, exp, sqrt,
  • Utility : max, min, clamp, mix (linear interpolation)
  • ID: isnan, isinf
  • Geometry: length, distance, dot, cross, normalize
  • Matrix: transpose, determinant, inverse
• User Defined Functions
  • type identifier([access modifier] type id, ...)
  • void return type is permitted
  • access modifiers
    • in: default, pass by value
    • const in: as you would expect, pass by constant value
    • out: value is undefined on invocation, copied out on exit
    • inout: pass by reference
  • Body as in C
• There is a preprocessor
  • #ifdef, #define, #undef, #ifndef, #else, #elif, #endif