Shader Macros Define

Similar to code referencing, in addition to directly referencing shaders, we can also selectively load code using simple macro (if-else-endif) statements.

For example, to create two material shaders, one with lighting and one without lighting, with all other code being the same, we can use the USE_LIGHT macro variable to flexibly load different shader code:

// Load global shader
#include `GlobalUniform`

// Choose to load different shader code based on the USE_LIGHT macro definition
#if USE_LIGHT
    #include `shader1`
#else
    #include `shader2`
#endif

// Other code
...

For more information on macro definitions, see the next chapter on Shader Variants