Data Access Functions

Functions
int	zsl_clr_illum_get (enum zsl_clr_obs obs, enum zsl_clr_illum illum, const struct zsl_clr_illum_data **data)
	Retrieves a pointer to the zsl_clr_illum_data for the specified illuminant. More...
void	zsl_clr_obs_get (enum zsl_clr_obs obs, const struct zsl_clr_obs_data **data)
	Retrieves a pointer to the zsl_clr_obs_data for the specified CIE standard observer model. More...
void	zsl_clr_lef_get (enum zsl_clr_lef lef, const struct zsl_clr_spd **data)
	Retrieves a pointer to the zsl_clr_spd data for the specified CIE luminous efficiency function. More...
int	zsl_clr_lef_lerp (enum zsl_clr_lef lef, unsigned int nm, zsl_real_t *val)
	Interpolates a single value from the specified CIE luminous efficiency function using linear interpolation. More...
void	zsl_clr_rgbccm_get (enum zsl_clr_rgb_ccm ccm, struct zsl_mtx **mtx)
	Retrieves a pointer to a standard 3x3 XYZ to RGB color space correlation matrix. More...

Detailed Description

Function to access various colorimetry datasets.

Function Documentation

zsl_clr_illum_get()

int zsl_clr_illum_get	(	enum zsl_clr_obs	obs,
		enum zsl_clr_illum	illum,
		const struct zsl_clr_illum_data **	data
	)

Retrieves a pointer to the zsl_clr_illum_data for the specified illuminant.

Parameters

obs	The standard observer associated with this #illum.
illum	The illuminant whose data should be retrieved.
data	Pointer to the pointer where the const zsl_clr_illum_data should be made accessible.

Returns

0 on normal execution, otherwise an appropriate error code.

Example

The following example shows how to use the pointer to a pointer mechnaism to access illuminant A data in an resource efficient manner.

void
get_illum(void)
{
    int rc;
    const struct zsl_clr_illum_data *illum;
 
    rc = zsl_clr_illum_get(ZSL_CLR_OBS_2_DEG, ZSL_CLR_ILLUM_A, &illum);
    if (rc) {
            // No matching illuminant found!
            return;
    }
 
    printf("Illum %s - x = %f\n", illum->name, illum->data.xyz_z);
}

zsl_clr_lef_get()

void zsl_clr_lef_get	(	enum zsl_clr_lef	lef,
		const struct zsl_clr_spd **	data
	)

Retrieves a pointer to the zsl_clr_spd data for the specified CIE luminous efficiency function.

Parameters

lef	The luminous efficiency func. whose data should be retrieved.
data	Pointer to the pointer where the const zsl_clr_spd data should be made accessible.

zsl_clr_lef_lerp()

int zsl_clr_lef_lerp	(	enum zsl_clr_lef	lef,
		unsigned int	nm,
		zsl_real_t *	val
	)

Interpolates a single value from the specified CIE luminous efficiency function using linear interpolation.

Parameters

lef	The luminous efficiency function to use.
nm	The wavelength to interpolate.
val	Pointer to the interpolated value's placeholder.

Returns

0 on normal execution, otherwise an appropriate error code.

zsl_clr_obs_get()

void zsl_clr_obs_get	(	enum zsl_clr_obs	obs,
		const struct zsl_clr_obs_data **	data
	)

Retrieves a pointer to the zsl_clr_obs_data for the specified CIE standard observer model.

Parameters

obs	The standard observer whose data should be retrieved.
data	Pointer to the pointer where the const zsl_clr_obs_data should be made accessible.

Returns

0 on normal execution, otherwise an appropriate error code.

Example

The following example shows how to use the pointer to a pointer mechnaism to access standard 2 degree observer data in an resource efficient manner.

void
get_stdobs(void)
{
    const struct zsl_clr_obs_data *obs;
 
    zsl_clr_obs_get(ZSL_CLR_OBS_2DEG, &obs);
    printf("obs: %s\n", obs->name);
}

zsl_clr_rgbccm_get()

void zsl_clr_rgbccm_get	(	enum zsl_clr_rgb_ccm	ccm,
		struct zsl_mtx **	mtx
	)

Retrieves a pointer to a standard 3x3 XYZ to RGB color space correlation matrix.

Parameters

ccm	The XYZ to RGB color space correlation matrix to retrieve.
mtx	Pointer to the pointer where the const zsl_mtx data should be made accessible.

Returns

0 on normal execution, otherwise an appropriate error code.