Merge branch 'color-management' into 'master'

Draft: Add support for ICC profiles for outputs

See merge request wlroots/wlroots!3804

include/render/gles2.h

@@ -22,6 +22,13 @@ struct wlr_gles2_pixel_format {
 	bool has_alpha;
 };
 
+struct wlr_gles2_quad_shader {
+	GLuint program;
+	GLint proj;
+	GLint color;
+	GLint pos_attrib;
+};
+
 struct wlr_gles2_tex_shader {
 	GLuint program;
 	GLint proj;
@@ -57,15 +64,11 @@ struct wlr_gles2_renderer {
 		PFNGLPUSHDEBUGGROUPKHRPROC glPushDebugGroupKHR;
 		PFNGLEGLIMAGETARGETRENDERBUFFERSTORAGEOESPROC glEGLImageTargetRenderbufferStorageOES;
 		PFNGLGETGRAPHICSRESETSTATUSKHRPROC glGetGraphicsResetStatusKHR;
+		PFNGLTEXIMAGE3DOESPROC glTexImage3DOES;
 	} procs;
 
 	struct {
-		struct {
-			GLuint program;
-			GLint proj;
-			GLint color;
-			GLint pos_attrib;
-		} quad;
+		struct wlr_gles2_quad_shader quad;
 		struct wlr_gles2_tex_shader tex_rgba;
 		struct wlr_gles2_tex_shader tex_rgbx;
 		struct wlr_gles2_tex_shader tex_ext;
@@ -112,6 +115,22 @@ struct wlr_gles2_texture {
 	struct wlr_addon buffer_addon;
 };
 
+enum wlr_gles2_shader_source {
+	WLR_GLES2_SHADER_SOURCE_SINGLE_COLOR = 1,
+	WLR_GLES2_SHADER_SOURCE_TEXTURE_RGBA = 2,
+	WLR_GLES2_SHADER_SOURCE_TEXTURE_RGBX = 3,
+	WLR_GLES2_SHADER_SOURCE_TEXTURE_EXTERNAL = 4,
+};
+
+enum wlr_gles2_shader_color_transform {
+	WLR_GLES2_SHADER_COLOR_TRANSFORM_IDENTITY = 0,
+	WLR_GLES2_SHADER_COLOR_TRANSFORM_LUT_3D = 1,
+};
+
+struct wlr_gles2_shader_params {
+	enum wlr_gles2_shader_source source;
+	enum wlr_gles2_shader_color_transform color_transform;
+};
 
 bool is_gles2_pixel_format_supported(const struct wlr_gles2_renderer *renderer,
 	const struct wlr_gles2_pixel_format *format);

include/wlr/render/color.h

@@ -0,0 +1,44 @@
+/*
+ * This an unstable interface of wlroots. No guarantees are made regarding the
+ * future consistency of this API.
+ */
+#ifndef WLR_USE_UNSTABLE
+#error "Add -DWLR_USE_UNSTABLE to enable unstable wlroots features"
+#endif
+
+#ifndef WLR_RENDER_COLOR_H
+#define WLR_RENDER_COLOR_H
+
+#include <stdbool.h>
+#include <sys/types.h>
+
+/**
+ * A color transformation formula.
+ *
+ * The formula is approximated via a 3D look-up table. A 3D LUT is a
+ * three-dimensional array where each element is an RGB triplet. The flat lut_3d
+ * array has a length of dim_len³.
+ *
+ * Color channel values in the range [0.0, 1.0] are mapped linearly to
+ * 3D LUT indices such that 0.0 maps exactly to the first element and 1.0 maps
+ * exactly to the last element in each dimension.
+ *
+ * The offset of the RGB triplet given red, green and blue indices r_index,
+ * g_index and b_index is:
+ *
+ *     offset = 3 * (r_index + dim_len * g_index + dim_len * dim_len * b_index)
+ */
+struct wlr_color_transform {
+	float *lut_3d;
+	size_t dim_len;
+};
+
+/**
+ * Initialize a color transformation to convert sRGB to an ICC profile.
+ */
+bool wlr_color_transform_init_srgb_to_icc(struct wlr_color_transform *tr,
+	const void *data, size_t size);
+
+void wlr_color_transform_finish(struct wlr_color_transform *tr);
+
+#endif