The global_settings statement is a catch-all statement that gathers together a number of global parameters. The statement may appear anywhere in a scene as long as it is not inside any other statement. You may have multiple global_settings statements in a scene. Whatever values were specified in the last global_settings statement override any previous settings. Regardless of where you specify the statement, the feature applies to the entire scene.
Note that some items which were language directives in earlier versions of POV-Ray have been moved inside the global_settings statement so that it is more obvious to the user that their effect is global. The old syntax is permitted but generates a warning. The new syntax is:
global_settings { }
adc_bailout ambient_light COLOR | assumed_gamma Value |
hf_gray_16 irid_wavelength COLOR | max_intersections Number |
max_trace_level number_of_waves Number |
radiosity { }
Each item is optional and may appear in and order. If an item is specified more than once, the last setting overrides previous values. Details on each item are given in the following sections.