gl-renderer: add support for (a|x)bgr16161616 shm formats

These formats are useful because they are often easier to produce
on CPU than half-float formats, and abgr16161616 has both >= 10bpc
color channels and adequate alpha, unlike abgr2101010.

The 16-bpc textures created from buffers with these formats require
the GL_EXT_texture_norm16 extension.

As WL_SHM_FORMAT_ABGR16161616 was introduced in libwayland 1.20,
update Weston's build requirements and CI.

The formats also needed to be registered in the pixel format table,
and defined in a fallback path if recent libdrm is not available.

Signed-off-by: Manuel Stoeckl <code@mstoeckl.com>

.gitlab-ci.yml

@@ -43,7 +43,7 @@
 variables:
   FDO_UPSTREAM_REPO: wayland/weston
   FDO_REPO_SUFFIX: "$BUILD_OS/$BUILD_ARCH"
-  FDO_DISTRIBUTION_TAG: '2021-11-25.0-dmabuf-feedback'
+  FDO_DISTRIBUTION_TAG: '2022-01-22.0-for-axbgr16161616'
 
 
 include:

.gitlab-ci/build-deps.sh

@@ -94,7 +94,7 @@ fi
 
 # Build and install Wayland; keep this version in sync with our dependency
 # in meson.build.
-git clone --branch 1.18.0 --depth=1 https://gitlab.freedesktop.org/wayland/wayland
+git clone --branch 1.20.0 --depth=1 https://gitlab.freedesktop.org/wayland/wayland
 cd wayland
 git show -s HEAD
 mkdir build

libweston/pixel-formats.c

@@ -332,6 +332,15 @@ static const struct pixel_format_info pixel_format_table[] = {
 		BITS_RGBA_FIXED(10, 10, 10, 2),
 		.opaque_substitute = DRM_FORMAT_BGRX1010102,
 	},
+	{
+		DRM_FORMAT(XBGR16161616),
+		BITS_RGBA_FIXED(16, 16, 16, 0),
+	},
+	{
+		DRM_FORMAT(ABGR16161616),
+		BITS_RGBA_FIXED(16, 16, 16, 16),
+		.opaque_substitute = DRM_FORMAT_XBGR16161616,
+	},
 	{
 		DRM_FORMAT(YUYV),
 		SAMPLER_TYPE(EGL_TEXTURE_Y_XUXV_WL),

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

@@ -156,6 +156,7 @@ struct gl_renderer {
 
 	bool has_texture_type_2_10_10_10_rev;
 	bool has_gl_texture_rg;
+	bool has_texture_norm16;
 
 	struct gl_shader *current_shader;
 	struct gl_shader *fallback_shader;

libweston/renderer-gl/gl-renderer.c

@@ -1822,6 +1822,7 @@ gl_format_from_internal(GLenum internal_format)
 		return GL_RED_EXT;
 	case GL_RG8_EXT:
 		return GL_RG_EXT;
+	case GL_RGBA16_EXT:
 	case GL_RGBA16F:
 	case GL_RGB10_A2:
 		return GL_RGBA;
@@ -2035,6 +2036,24 @@ gl_renderer_attach_shm(struct weston_surface *es, struct weston_buffer *buffer,
 		gl_pixel_type = GL_HALF_FLOAT;
 		es->is_opaque = true;
 		break;
+	case WL_SHM_FORMAT_ABGR16161616:
+		if (!gr->has_texture_norm16)
+			goto unsupported;
+		gs->shader_variant = SHADER_VARIANT_RGBA;
+		pitch = wl_shm_buffer_get_stride(shm_buffer) / 8;
+		gl_format[0] = GL_RGBA16_EXT;
+		gl_pixel_type = GL_UNSIGNED_SHORT;
+		es->is_opaque = false;
+		break;
+	case WL_SHM_FORMAT_XBGR16161616:
+		if (!gr->has_texture_norm16)
+			goto unsupported;
+		gs->shader_variant = SHADER_VARIANT_RGBX;
+		pitch = wl_shm_buffer_get_stride(shm_buffer) / 8;
+		gl_format[0] = GL_RGBA16_EXT;
+		gl_pixel_type = GL_UNSIGNED_SHORT;
+		es->is_opaque = true;
+		break;
 #endif
 	case WL_SHM_FORMAT_YUV420:
 		gs->shader_variant = SHADER_VARIANT_Y_U_V;
@@ -3766,6 +3785,10 @@ gl_renderer_display_create(struct weston_compositor *ec,
 		wl_display_add_shm_format(ec->wl_display, WL_SHM_FORMAT_ABGR16161616F);
 		wl_display_add_shm_format(ec->wl_display, WL_SHM_FORMAT_XBGR16161616F);
 	}
+	if (gr->has_texture_norm16) {
+		wl_display_add_shm_format(ec->wl_display, WL_SHM_FORMAT_ABGR16161616);
+		wl_display_add_shm_format(ec->wl_display, WL_SHM_FORMAT_XBGR16161616);
+	}
 #endif
 
 	if (gr->gl_supports_color_transforms)
@@ -3942,6 +3965,9 @@ gl_renderer_setup(struct weston_compositor *ec, EGLSurface egl_surface)
 	    weston_check_egl_extension(extensions, "GL_EXT_texture_type_2_10_10_10_REV"))
 		gr->has_texture_type_2_10_10_10_rev = true;
 
+	if (weston_check_egl_extension(extensions, "GL_EXT_texture_norm16"))
+		gr->has_texture_norm16 = true;
+
 	if (gr->gl_version >= gr_gl_version(3, 0) ||
 	    weston_check_egl_extension(extensions, "GL_EXT_texture_rg"))
 		gr->has_gl_texture_rg = true;

meson.build

@@ -145,8 +145,8 @@ if get_option('deprecated-wl-shell')
 	config_h.set('HAVE_DEPRECATED_WL_SHELL', '1')
 endif
 
-dep_wayland_server = dependency('wayland-server', version: '>= 1.18.0')
-dep_wayland_client = dependency('wayland-client', version: '>= 1.18.0')
+dep_wayland_server = dependency('wayland-server', version: '>= 1.20.0')
+dep_wayland_client = dependency('wayland-client', version: '>= 1.20.0')
 dep_pixman = dependency('pixman-1', version: '>= 0.25.2')
 dep_libinput = dependency('libinput', version: '>= 0.8.0')
 dep_libevdev = dependency('libevdev')

shared/weston-drm-fourcc.h

@@ -38,4 +38,12 @@
 #define DRM_FORMAT_XYUV8888      fourcc_code('X', 'Y', 'U', 'V') /* [31:0] X:Y:Cb:Cr 8:8:8:8 little endian */
 #endif
 
+#ifndef DRM_FORMAT_XBGR16161616
+#define DRM_FORMAT_XBGR16161616  fourcc_code('X', 'B', '4', '8') /* [63:0] x:B:G:R 16:16:16:16 little endian */
+#endif
+
+#ifndef DRM_FORMAT_ABGR16161616
+#define DRM_FORMAT_ABGR16161616  fourcc_code('A', 'B', '4', '8') /* [63:0] A:B:G:R 16:16:16:16 little endian */
+#endif
+
 #endif