Global Settings

## 6.11 Global Settings

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.

Note: 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:
        global_settings { [GLOBAL_SETTINGS_ITEMS...] }
    GLOBAL_SETTINGS_ITEM:
        adc_bailout Value | ambient_light COLOR | assumed_gamma Value |
        hf_gray_16 [Bool] | irid_wavelength COLOR |
        charset GLOBAL_CHARSET | max_intersections Number |
        max_trace_level Number | number_of_waves Number |
        noise_generator Number | radiosity { RADIOSITY_ITEMS... } |
        photon { PHOTON_ITEMS... }
    GLOBAL_CHARSET:
        ascii | utf8 | sys

Global setting default values:

    CHARSET            : ascii
    adc_bailout        : 1/255
    ambient_light      : <1,1,1>
    assumed_gamma      : No gamma correction
    hf_gray_16         : off
    irid_wavelength    : <0.25,0.18,0.14>
    max_trace_level    : 5
    max_intersections  : 64
    number_of_waves    : 10
    noise_generator    : 2

    Radiosity:
      adc_bailout      : 0.01
      always_sample    : on
      brightness       : 1.0
      count            : 35  (max = 1600)
      error_bound      : 1.8
      gray_threshold   : 0.0
      low_error_factor : 0.5
      max_sample       : non-positive value
      minimum_reuse    : 0.015
      nearest_count    : 5   (max = 20)
      normal           : off
      pretrace_start   : 0.08
      pretrace_end     : 0.04
      recursion_limit  : 3

Each item is optional and may appear in any 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.

In 'Global Settings' ...
6.11.1 | ADC_Bailout
6.11.2 | Ambient_Light
6.11.3 | Assumed_Gamma
6.11.4 | HF_Gray_16
6.11.5 | Irid_Wavelength
6.11.6 | Charset
6.11.7 | Max_Trace_Level
6.11.8 | Max_Intersections
6.11.9 | Number_Of_Waves
6.11.10 | Noise_generator
6.11.11 | Radiosity