wlroots/include/render/color.h

#ifndef RENDER_COLOR_H
#define RENDER_COLOR_H

#include <stdint.h>
#include <wlr/render/color.h>
#include <wlr/util/addon.h>

enum wlr_color_transform_type {
	COLOR_TRANSFORM_SRGB,
	COLOR_TRANSFORM_LCMS2,
};

struct wlr_color_transform {
	int ref_count;
	struct wlr_addon_set addons; // per-renderer helper state

	enum wlr_color_transform_type type;
};

void wlr_color_transform_init(struct wlr_color_transform *tr,
	enum wlr_color_transform_type type);

/**
 * Get a struct wlr_color_transform_lcms2 from a generic struct wlr_color_transform.
 * Asserts that the base type is COLOR_TRANSFORM_LCMS2.
 */
struct wlr_color_transform_lcms2 *color_transform_lcms2_from_base(
	struct wlr_color_transform *tr);

void color_transform_lcms2_finish(struct wlr_color_transform_lcms2 *tr);

/**
 * Evaluate a LCMS2 color transform for a given RGB triplet.
 */
void color_transform_lcms2_eval(struct wlr_color_transform_lcms2 *tr,
	float out[static 3], const float in[static 3]);

/**
 * Obtain primaries values from a well-known primaries name.
 */
void wlr_color_primaries_from_named(struct wlr_color_primaries *out,
	enum wlr_color_named_primaries named);

/**
 * Compute the matrix to convert RGB color values to CIE 1931 XYZ.
 */
void wlr_color_primaries_to_xyz(const struct wlr_color_primaries *primaries, float matrix[static 9]);

/**
 * Get default luminances for a transfer function.
 */
void wlr_color_transfer_function_get_default_luminance(enum wlr_color_transfer_function tf,
	struct wlr_color_luminances *lum);

#endif