renderer-gl: Support more shm RGB formats

Some applications, e.g. Chromium browser, may provide ABGR format buf.

Tested with gstreamer 1.22.8:
gst-launch-1.0 videotestsrc ! 'video/x-raw,format=RGB' ! waylandsink
gst-launch-1.0 videotestsrc ! 'video/x-raw,format=BGR' ! waylandsink
gst-launch-1.0 videotestsrc ! 'video/x-raw,format=ARGB' ! waylandsink
gst-launch-1.0 videotestsrc ! 'video/x-raw,format=xRGB' ! waylandsink
gst-launch-1.0 videotestsrc ! 'video/x-raw,format=ABGR' ! waylandsink
gst-launch-1.0 videotestsrc ! 'video/x-raw,format=xBGR' ! waylandsink
gst-launch-1.0 videotestsrc ! 'video/x-raw,format=RGBA' ! waylandsink
gst-launch-1.0 videotestsrc ! 'video/x-raw,format=RGBx' ! waylandsink
gst-launch-1.0 videotestsrc ! 'video/x-raw,format=BGRA' ! waylandsink
gst-launch-1.0 videotestsrc ! 'video/x-raw,format=BGRx' ! waylandsink

Signed-off-by: Jeffy Chen <jeffy.chen@rock-chips.com>

libweston/pixel-formats.c

@@ -53,11 +53,14 @@
 #define GL_INTERNALFORMAT(fmt) .gl_internalformat = (fmt)
 #define GL_FORMAT(fmt) .gl_format = (fmt)
 #define GL_TYPE(type) .gl_type = (type)
+#define GL_CHANNEL_ORDER(order) \
+	.gl_channel_order = (SHADER_CHANNEL_ORDER_ ## order)
 #define SAMPLER_TYPE(type) .sampler_type = (type)
 #else
 #define GL_INTERNALFORMAT(fmt) .gl_internalformat = 0
 #define GL_FORMAT(fmt) .gl_format = 0
 #define GL_TYPE(type) .gl_type = 0
+#define GL_CHANNEL_ORDER(order) .gl_channel_order = 0
 #define SAMPLER_TYPE(type) .sampler_type = 0
 #endif
 
@@ -226,6 +229,9 @@ static const struct pixel_format_info pixel_format_table[] = {
 		DRM_FORMAT(RGB888),
 		BITS_RGBA_FIXED(8, 8, 8, 0),
 		.bpp = 24,
+		GL_FORMAT(GL_RGB),
+		GL_TYPE(GL_UNSIGNED_BYTE),
+		GL_CHANNEL_ORDER(BGRA),
 	},
 	{
 		DRM_FORMAT(BGR888),
@@ -292,6 +298,9 @@ static const struct pixel_format_info pixel_format_table[] = {
 		DRM_FORMAT(RGBX8888),
 		BITS_RGBA_FIXED(8, 8, 8, 0),
 		.bpp = 32,
+		GL_FORMAT(GL_RGBA),
+		GL_TYPE(GL_UNSIGNED_BYTE),
+		GL_CHANNEL_ORDER(ABGR),
 #if __BYTE_ORDER == __LITTLE_ENDIAN
 		PIXMAN_FMT(r8g8b8x8),
 #else
@@ -303,6 +312,9 @@ static const struct pixel_format_info pixel_format_table[] = {
 		BITS_RGBA_FIXED(8, 8, 8, 8),
 		.bpp = 32,
 		.opaque_substitute = DRM_FORMAT_RGBX8888,
+		GL_FORMAT(GL_RGBA),
+		GL_TYPE(GL_UNSIGNED_BYTE),
+		GL_CHANNEL_ORDER(ABGR),
 #if __BYTE_ORDER == __LITTLE_ENDIAN
 		PIXMAN_FMT(r8g8b8a8),
 #else
@@ -313,6 +325,9 @@ static const struct pixel_format_info pixel_format_table[] = {
 		DRM_FORMAT(BGRX8888),
 		BITS_RGBA_FIXED(8, 8, 8, 0),
 		.bpp = 32,
+		GL_FORMAT(GL_RGBA),
+		GL_TYPE(GL_UNSIGNED_BYTE),
+		GL_CHANNEL_ORDER(ARGB),
 #if __BYTE_ORDER == __LITTLE_ENDIAN
 		PIXMAN_FMT(b8g8r8x8),
 #else
@@ -324,6 +339,9 @@ static const struct pixel_format_info pixel_format_table[] = {
 		BITS_RGBA_FIXED(8, 8, 8, 8),
 		.bpp = 32,
 		.opaque_substitute = DRM_FORMAT_BGRX8888,
+		GL_FORMAT(GL_RGBA),
+		GL_TYPE(GL_UNSIGNED_BYTE),
+		GL_CHANNEL_ORDER(ARGB),
 #if __BYTE_ORDER == __LITTLE_ENDIAN
 		PIXMAN_FMT(b8g8r8a8),
 #else

libweston/pixel-formats.h

@@ -28,6 +28,14 @@
 #include <stdbool.h>
 #include <pixman.h>
 
+/* Keep the following in sync with fragment.glsl. */
+enum gl_channel_order {
+	SHADER_CHANNEL_ORDER_RGBA = 0,
+	SHADER_CHANNEL_ORDER_BGRA,
+	SHADER_CHANNEL_ORDER_ARGB,
+	SHADER_CHANNEL_ORDER_ABGR,
+};
+
 /**
  * Contains information about pixel formats, mapping format codes from
  * wl_shm and drm_fourcc.h (which are deliberately identical, but for the
@@ -78,6 +86,11 @@ struct pixel_format_info {
 	/** GL data type, if data can be natively/directly uploaded. */
 	int gl_type;
 
+	/** This enumeration tells the resulting order of the color channels
+	 * when the DRM formatted pixel data is read with the given gl_format
+	 * and gl_type. */
+	enum gl_channel_order gl_channel_order;
+
 	/** Pixman data type, if it agrees exactly with the wl_shm format */
 	pixman_format_code_t pixman_format;
 

libweston/renderer-gl/fragment.glsl

@@ -54,6 +54,12 @@
 #define SHADER_COLOR_MAPPING_3DLUT 1
 #define SHADER_COLOR_MAPPING_MATRIX 2
 
+/* enum gl_channel_order */
+#define SHADER_CHANNEL_ORDER_RGBA 0
+#define SHADER_CHANNEL_ORDER_BGRA 1
+#define SHADER_CHANNEL_ORDER_ARGB 2
+#define SHADER_CHANNEL_ORDER_ABGR 3
+
 #if DEF_VARIANT == SHADER_VARIANT_EXTERNAL
 #extension GL_OES_EGL_image_external : require
 #endif
@@ -78,6 +84,7 @@ compile_const int c_variant = DEF_VARIANT;
 compile_const int c_color_pre_curve = DEF_COLOR_PRE_CURVE;
 compile_const int c_color_mapping = DEF_COLOR_MAPPING;
 compile_const int c_color_post_curve = DEF_COLOR_POST_CURVE;
+compile_const int c_color_channel_order = DEF_COLOR_CHANNEL_ORDER;
 
 compile_const bool c_input_is_premult = DEF_INPUT_IS_PREMULT;
 compile_const bool c_green_tint = DEF_GREEN_TINT;
@@ -158,13 +165,27 @@ sample_input_texture()
 	if (c_variant == SHADER_VARIANT_SOLID)
 		return unicolor;
 
-	if (c_variant == SHADER_VARIANT_RGBA ||
+	if (c_variant == SHADER_VARIANT_EXTERNAL)
-	    c_variant == SHADER_VARIANT_EXTERNAL) {
 		return texture2D(tex, v_texcoord);
-	}
 
-	if (c_variant == SHADER_VARIANT_RGBX)
+	if (c_variant == SHADER_VARIANT_RGBA ||
-		return vec4(texture2D(tex, v_texcoord).rgb, 1.0);
+	    c_variant == SHADER_VARIANT_RGBX) {
+		vec4 color;
+
+		if (c_color_channel_order == SHADER_CHANNEL_ORDER_BGRA)
+			color = texture2D(tex, v_texcoord).bgra;
+		else if (c_color_channel_order == SHADER_CHANNEL_ORDER_ARGB)
+			color = texture2D(tex, v_texcoord).gbar;
+		else if (c_color_channel_order == SHADER_CHANNEL_ORDER_ABGR)
+			color = texture2D(tex, v_texcoord).abgr;
+		else
+			color = texture2D(tex, v_texcoord);
+
+		if (c_variant == SHADER_VARIANT_RGBX)
+			color.a = 1.0;
+
+		return color;
+	}
 
 	/* Requires conversion to RGBA */
 

libweston/renderer-gl/gl-renderer-internal.h

@@ -99,11 +99,13 @@ struct gl_shader_requirements
 	unsigned color_pre_curve:2; /* enum gl_shader_color_curve */
 	unsigned color_mapping:2; /* enum gl_shader_color_mapping */
 	unsigned color_post_curve:2; /* enum gl_shader_color_curve */
+	unsigned color_channel_order:2; /* enum gl_channel_order */
+
 	/*
 	 * The total size of all bitfields plus pad_bits_ must fill up exactly
 	 * how many bytes the compiler allocates for them together.
 	 */
-	unsigned pad_bits_:18;
+	unsigned pad_bits_:16;
 };
 static_assert(sizeof(struct gl_shader_requirements) ==
 	      4 /* total bitfield size in bytes */,

libweston/renderer-gl/gl-renderer.c

@@ -180,6 +180,7 @@ struct gl_buffer_state {
 	int pitch; /* plane 0 pitch in pixels */
 	GLenum gl_pixel_type;
 	GLenum gl_format[3];
+	enum gl_channel_order gl_channel_order;
 	int offset[3]; /* per-plane pitch in bytes */
 
 	EGLImageKHR images[3];
@@ -1134,6 +1135,7 @@ gl_shader_config_set_input_textures(struct gl_shader_config *sconf,
 	int i;
 
 	sconf->req.variant = gb->shader_variant;
+	sconf->req.color_channel_order = gb->gl_channel_order;
 	sconf->req.input_is_premult =
 		gl_shader_texture_variant_can_be_premult(gb->shader_variant);
 
@@ -2697,6 +2699,7 @@ gl_renderer_attach_shm(struct weston_surface *es, struct weston_buffer *buffer)
 	gb->shader_variant = shader_variant;
 	ARRAY_COPY(gb->offset, offset);
 	ARRAY_COPY(gb->gl_format, gl_format);
+	gb->gl_channel_order = buffer->pixel_format->gl_channel_order;
 	gb->gl_pixel_type = gl_pixel_type;
 	gb->needs_full_upload = true;
 
@@ -4271,6 +4274,14 @@ gl_renderer_display_create(struct weston_compositor *ec,
 	if (gl_renderer_setup(ec) < 0)
 		goto fail_with_error;
 
+	wl_display_add_shm_format(ec->wl_display, WL_SHM_FORMAT_XBGR8888);
+	wl_display_add_shm_format(ec->wl_display, WL_SHM_FORMAT_ABGR8888);
+	wl_display_add_shm_format(ec->wl_display, WL_SHM_FORMAT_RGBX8888);
+	wl_display_add_shm_format(ec->wl_display, WL_SHM_FORMAT_RGBA8888);
+	wl_display_add_shm_format(ec->wl_display, WL_SHM_FORMAT_BGRX8888);
+	wl_display_add_shm_format(ec->wl_display, WL_SHM_FORMAT_BGRA8888);
+	wl_display_add_shm_format(ec->wl_display, WL_SHM_FORMAT_RGB888);
+	wl_display_add_shm_format(ec->wl_display, WL_SHM_FORMAT_BGR888);
 	wl_display_add_shm_format(ec->wl_display, WL_SHM_FORMAT_RGB565);
 	wl_display_add_shm_format(ec->wl_display, WL_SHM_FORMAT_YUV420);
 	wl_display_add_shm_format(ec->wl_display, WL_SHM_FORMAT_YUV444);

libweston/renderer-gl/gl-shaders.c

@@ -42,6 +42,7 @@
 
 #include "gl-renderer.h"
 #include "gl-renderer-internal.h"
+#include "pixel-formats.h"
 #include "shared/helpers.h"
 #include "shared/timespec-util.h"
 
@@ -153,6 +154,21 @@ gl_shader_color_mapping_to_string(enum gl_shader_color_mapping kind)
 	return "!?!?"; /* never reached */
 }
 
+static const char *
+gl_shader_color_order_to_string(enum gl_channel_order kind)
+{
+	switch (kind) {
+#define CASERET(x) case x: return #x;
+	CASERET(SHADER_CHANNEL_ORDER_RGBA)
+	CASERET(SHADER_CHANNEL_ORDER_BGRA)
+	CASERET(SHADER_CHANNEL_ORDER_ARGB)
+	CASERET(SHADER_CHANNEL_ORDER_ABGR)
+#undef CASERET
+	}
+
+	return "!?!?"; /* never reached */
+}
+
 static void
 dump_program_with_line_numbers(int count, const char **sources)
 {
@@ -218,12 +234,13 @@ create_shader_description_string(const struct gl_shader_requirements *req)
 	int size;
 	char *str;
 
-	size = asprintf(&str, "%s %s %s %s %s %cinput_is_premult %cgreen",
+	size = asprintf(&str, "%s %s %s %s %s %s %cinput_is_premult %cgreen",
 			gl_shader_texcoord_input_to_string(req->texcoord_input),
 			gl_shader_texture_variant_to_string(req->variant),
 			gl_shader_color_curve_to_string(req->color_pre_curve),
 			gl_shader_color_mapping_to_string(req->color_mapping),
 			gl_shader_color_curve_to_string(req->color_post_curve),
+			gl_shader_color_order_to_string(req->color_channel_order),
 			req->input_is_premult ? '+' : '-',
 			req->green_tint ? '+' : '-');
 	if (size < 0)
@@ -254,6 +271,10 @@ create_fragment_shader_config_string(const struct gl_shader_requirements *req)
 	int size;
 	char *str;
 
+	/* EXTERNAL can only be used with identity swizzle */
+	assert(req->variant != SHADER_VARIANT_EXTERNAL ||
+	       req->color_channel_order == SHADER_CHANNEL_ORDER_RGBA);
+
 	size = asprintf(&str,
 			"#define DEF_GREEN_TINT %s\n"
 			"#define DEF_INPUT_IS_PREMULT %s\n"
@@ -261,6 +282,7 @@ create_fragment_shader_config_string(const struct gl_shader_requirements *req)
 			"#define DEF_COLOR_PRE_CURVE %s\n"
 			"#define DEF_COLOR_MAPPING %s\n"
 			"#define DEF_COLOR_POST_CURVE %s\n"
+			"#define DEF_COLOR_CHANNEL_ORDER %s\n"
 			"#define DEF_VARIANT %s\n",
 			req->green_tint ? "true" : "false",
 			req->input_is_premult ? "true" : "false",
@@ -268,6 +290,7 @@ create_fragment_shader_config_string(const struct gl_shader_requirements *req)
 			gl_shader_color_curve_to_string(req->color_pre_curve),
 			gl_shader_color_mapping_to_string(req->color_mapping),
 			gl_shader_color_curve_to_string(req->color_post_curve),
+			gl_shader_color_order_to_string(req->color_channel_order),
 			gl_shader_texture_variant_to_string(req->variant));
 	if (size < 0)
 		return NULL;