Gamma correction functions
[General DC operations]

Defines

• #define SetGamma   GAL_SetGamma

  Is an alias of GAL_SetGamma.
  

• #define SetGammaRamp   GAL_SetGammaRamp

  Is an alias of GAL_SetGammaRamp.
  

• #define GetGammaRamp   GAL_GetGammaRamp

  Is an alias of GAL_GetGammaRamp.
  

Functions

• int GAL_SetGamma (float red, float green, float blue)

  Sets the gamma correction for each of the color channels.
  

• int GAL_SetGammaRamp (Uint16 *red, Uint16 *green, Uint16 *blue)

  Sets the gamma translation table for the red, green, and blue channels of the video hardware.
  

• int GAL_GetGammaRamp (Uint16 *red, Uint16 *green, Uint16 *blue)

  Retrieves the current values of the gamma translation tables.
  

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Define Documentation

#define GetGammaRamp   GAL_GetGammaRamp

Is an alias of GAL_GetGammaRamp. See also: GAL_GetGammaRamp Definition at line 1845 of file gdi.h.

#define SetGamma   GAL_SetGamma

Is an alias of GAL_SetGamma. See also: GAL_SetGamma Definition at line 1779 of file gdi.h.

#define SetGammaRamp   GAL_SetGammaRamp

Is an alias of GAL_SetGammaRamp. See also: GAL_SetGammaRamp Definition at line 1813 of file gdi.h.

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Function Documentation

int GAL_GetGammaRamp (  Uint16 *  red, Uint16 *  green, Uint16 *  blue )

Retrieves the current values of the gamma translation tables. This function retrives the current values of the gamma translationn tables. You must pass in valid pointers to arrays of 256 16-bit quantities. Any of the pointers may be NULL to ignore that channel. Parameters: red  Pointers to the array of gamma translation tables for the red channel. green  Pointers to the array of gamma translation tables for the green channel. blue  Pointers to the array of gamma translation tables for the blue channel. Returns: If the call succeeds, it will return 0. If the display driver or hardware does not support gamma translation, or otherwise fails, this function will return -1. Note: Only defined for _USE_NEWGAL. See also: GAL_SetGammaRamp

int GAL_SetGamma (  float  red, float  green, float  blue )

Sets the gamma correction for each of the color channels. This function sets the gamma correction for each of the color channels. The gamma values range (approximately) between 0.1 and 10.0. If this function isn't supported directly by the hardware, it will be emulated using gamma ramps, if available. Parameters: red  The gamma correction value of red channel. green  The gamma correction value of green channel. blue  The gamma correction value of blue channel. Returns: If successful, this function returns 0, otherwise it returns -1. Note: Only defined for _USE_NEWGAL. See also: GAL_SetGammaRamp

int GAL_SetGammaRamp (  Uint16 *  red, Uint16 *  green, Uint16 *  blue )

Sets the gamma translation table for the red, green, and blue channels of the video hardware. This function sets the gamma translation table for the red, green, and blue channels of the video hardware. Each table is an array of 256 16-bit quantities, representing a mapping between the input and output for that channel. The input is the index into the array, and the output is the 16-bit gamma value at that index, scaled to the output color precision. You may pass NULL for any of the channels to leave it unchanged. Parameters: red  The gamma translation table for the red channel. green  The gamma translation table for the green channel. blue  The gamma translation table for the blue channel. Returns: If the call succeeds, it will return 0. If the display driver or hardware does not support gamma translation, or otherwise fails, this function will return -1. Note: Only defined for _USE_NEWGAL. See also: GAL_GetGammaRamp, GAL_SetGamma

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