Built-in functions – Debugging functions
print(real x) real
print(int x) int
print(bool x) bool
print(vec2 x) vec2
print(vec3 x) vec3
print(mat2x2 x) mat2x2
print(mat3x3 x) mat3x3

Prints the value of x to standard output, then returns it.

If there are multiple calls to print in a shader, the function calls are not guaranteed to execute in any particular order.

To view the standard output from Indigo, you will need to run the console version of Indigo - indigo_console. (indigo_console.exe on Windows etc..)