Bug 1675590 - avoid using alpha-pass version of gradient shader for... (b9384b09) · Commits · clairehurst / Tor Browser

gfx/wr/webrender/res/brush.glsl

+5 −1

Original line number	Diff line number	Diff line
		@@ -156,7 +156,11 @@ void brush_shader_main_vs(
		// shaders that don't clip in the future,
		// but it's reasonable to assume that one
		// implies the other, for now.
		#ifdef WR_FEATURE_ALPHA_PASS
		// SW-WR may decay some requests for alpha-pass shaders to
		// the opaque version if only the clip-mask is required. In
		// that case the opaque vertex shader must still write out
		// the clip information, which is cheap to do for SWGL.
		#if defined(WR_FEATURE_ALPHA_PASS) \|\| defined(SWGL)
		write_clip(
		vi.world_pos,
		clip_area,

gfx/wr/webrender/src/device/gl.rs

+10 −0

Original line number	Diff line number	Diff line
		@@ -981,6 +981,9 @@ pub struct Capabilities {
		/// Whether the driver prefers fewer and larger texture uploads
		/// over many smaller updates.
		pub prefers_batched_texture_uploads: bool,
		/// Whether clip-masking is supported natively by the GL implementation
		/// rather than emulated in shaders.
		pub uses_native_clip_mask: bool,
		/// The name of the renderer, as reported by GL
		pub renderer_name: String,
		}
		@@ -1627,6 +1630,12 @@ impl Device {
		gl::GlType::Gles => gl_version >= [3, 1],
		};

		// SWGL uses swgl_clipMask() instead of implementing clip-masking in shaders.
		// This allows certain shaders to potentially bypass the more expensive alpha-
		// pass variants if they know the alpha-pass was only required to deal with
		// clip-masking.
		let uses_native_clip_mask = is_software_webrender;

		// On Mali-Gxx the driver really struggles with many small texture uploads,
		// and handles fewer, larger uploads better.
		let prefers_batched_texture_uploads = is_mali_g;
		@@ -1654,6 +1663,7 @@ impl Device {
		supports_render_target_partial_update,
		supports_shader_storage_object,
		prefers_batched_texture_uploads,
		uses_native_clip_mask,
		renderer_name,
		},

gfx/wr/webrender/src/renderer/mod.rs

+2 −1

Original line number	Diff line number	Diff line
		@@ -3038,7 +3038,7 @@ impl Renderer {
		}

		self.shaders.borrow_mut()
		.get(&batch.key, batch.features, self.debug_flags)
		.get(&batch.key, batch.features, self.debug_flags, &self.device)
		.bind(
		&mut self.device, projection,
		&mut self.renderer_errors,
		@@ -3078,6 +3078,7 @@ impl Renderer {
		&batch.key,
		batch.features \| BatchFeatures::ALPHA_PASS,
		self.debug_flags,
		&self.device,
		);

		if batch.key.blend_mode != prev_blend_mode {

gfx/wr/webrender/src/renderer/shade.rs

+13 −23

Original line number	Diff line number	Diff line
		@@ -1060,6 +1060,7 @@ impl Shaders {
		key: &BatchKey,
		mut features: BatchFeatures,
		debug_flags: DebugFlags,
		device: &Device,
		) -> &mut LazilyCompiledShader {
		match key.kind {
		BatchKind::SplitComposite => {
		@@ -1089,19 +1090,15 @@ impl Shaders {
		BrushBatchKind::MixBlend { .. } => {
		&mut self.brush_mix_blend
		}
		BrushBatchKind::LinearGradient \|
		BrushBatchKind::RadialGradient \|
		BrushBatchKind::ConicGradient => {
		// Gradient brushes can optimistically use the opaque shader even
		// with a blend mode if they don't require any features.
		if !features.intersects(
		BatchFeatures::ANTIALIASING
		\| BatchFeatures::REPETITION
		\| BatchFeatures::CLIP_MASK,
		) {
		features.remove(BatchFeatures::ALPHA_PASS);
		}
		&mut self.brush_conic_gradient
		// SWGL uses a native clip mask implementation that bypasses the shader.
		// Don't consider it in that case when deciding whether or not to use
		// an alpha-pass shader.
		if device.get_capabilities().uses_native_clip_mask {
		features.remove(BatchFeatures::CLIP_MASK);
		}
		BrushBatchKind::RadialGradient => {
		// Gradient brushes can optimistically use the opaque shader even
		// with a blend mode if they don't require any features.
		if !features.intersects(
		@@ -1111,19 +1108,12 @@ impl Shaders {
		) {
		features.remove(BatchFeatures::ALPHA_PASS);
		}
		&mut self.brush_radial_gradient
		}
		BrushBatchKind::LinearGradient => {
		// Gradient brushes can optimistically use the opaque shader even
		// with a blend mode if they don't require any features.
		if !features.intersects(
		BatchFeatures::ANTIALIASING
		\| BatchFeatures::REPETITION
		\| BatchFeatures::CLIP_MASK,
		) {
		features.remove(BatchFeatures::ALPHA_PASS);
		match brush_kind {
		BrushBatchKind::LinearGradient => &mut self.brush_linear_gradient,
		BrushBatchKind::RadialGradient => &mut self.brush_radial_gradient,
		BrushBatchKind::ConicGradient => &mut self.brush_conic_gradient,
		_ => panic!(),
		}
		&mut self.brush_linear_gradient
		}
		BrushBatchKind::YuvImage(image_buffer_kind, ..) => {
		let shader_index =