[Impeller] Gaussian blur: Remove the current blur style implementation.

ci/licenses_golden/licenses_flutter

@@ -1329,8 +1329,6 @@ ORIGIN: ../../../flutter/impeller/entity/shaders/debug/checkerboard.frag + ../..
 ORIGIN: ../../../flutter/impeller/entity/shaders/debug/checkerboard.vert + ../../../flutter/LICENSE
 ORIGIN: ../../../flutter/impeller/entity/shaders/gaussian_blur/gaussian_blur.glsl + ../../../flutter/LICENSE
 ORIGIN: ../../../flutter/impeller/entity/shaders/gaussian_blur/gaussian_blur.vert + ../../../flutter/LICENSE
-ORIGIN: ../../../flutter/impeller/entity/shaders/gaussian_blur/gaussian_blur_alpha_decal.frag + ../../../flutter/LICENSE
-ORIGIN: ../../../flutter/impeller/entity/shaders/gaussian_blur/gaussian_blur_alpha_nodecal.frag + ../../../flutter/LICENSE
 ORIGIN: ../../../flutter/impeller/entity/shaders/gaussian_blur/gaussian_blur_noalpha_decal.frag + ../../../flutter/LICENSE
 ORIGIN: ../../../flutter/impeller/entity/shaders/gaussian_blur/gaussian_blur_noalpha_nodecal.frag + ../../../flutter/LICENSE
 ORIGIN: ../../../flutter/impeller/entity/shaders/geometry/points.comp + ../../../flutter/LICENSE
@@ -4075,8 +4073,6 @@ FILE: ../../../flutter/impeller/entity/shaders/debug/checkerboard.frag
 FILE: ../../../flutter/impeller/entity/shaders/debug/checkerboard.vert
 FILE: ../../../flutter/impeller/entity/shaders/gaussian_blur/gaussian_blur.glsl
 FILE: ../../../flutter/impeller/entity/shaders/gaussian_blur/gaussian_blur.vert
-FILE: ../../../flutter/impeller/entity/shaders/gaussian_blur/gaussian_blur_alpha_decal.frag
-FILE: ../../../flutter/impeller/entity/shaders/gaussian_blur/gaussian_blur_alpha_nodecal.frag
 FILE: ../../../flutter/impeller/entity/shaders/gaussian_blur/gaussian_blur_noalpha_decal.frag
 FILE: ../../../flutter/impeller/entity/shaders/gaussian_blur/gaussian_blur_noalpha_nodecal.frag
 FILE: ../../../flutter/impeller/entity/shaders/geometry/points.comp

impeller/entity/BUILD.gn

@@ -40,8 +40,6 @@ impeller_shaders("entity_shaders") {
     "shaders/color_matrix_color_filter.vert",
     "shaders/conical_gradient_fill.frag",
     "shaders/gaussian_blur/gaussian_blur.vert",
-    "shaders/gaussian_blur/gaussian_blur_alpha_decal.frag",
-    "shaders/gaussian_blur/gaussian_blur_alpha_nodecal.frag",
     "shaders/gaussian_blur/gaussian_blur_noalpha_decal.frag",
     "shaders/gaussian_blur/gaussian_blur_noalpha_nodecal.frag",
     "shaders/glyph_atlas.frag",

impeller/entity/contents/content_context.cc

@@ -282,10 +282,6 @@ ContentContext::ContentContext(
       CreateDefaultPipeline<PositionUVPipeline>(*context_);
   tiled_texture_pipelines_[default_options_] =
       CreateDefaultPipeline<TiledTexturePipeline>(*context_);
-  gaussian_blur_alpha_decal_pipelines_[default_options_] =
-      CreateDefaultPipeline<GaussianBlurAlphaDecalPipeline>(*context_);
-  gaussian_blur_alpha_nodecal_pipelines_[default_options_] =
-      CreateDefaultPipeline<GaussianBlurAlphaPipeline>(*context_);
   gaussian_blur_noalpha_decal_pipelines_[default_options_] =
       CreateDefaultPipeline<GaussianBlurDecalPipeline>(*context_);
   gaussian_blur_noalpha_nodecal_pipelines_[default_options_] =

impeller/entity/contents/content_context.h

@@ -63,8 +63,6 @@
 #include "impeller/entity/yuv_to_rgb_filter.vert.h"
 
 #include "impeller/entity/gaussian_blur.vert.h"
-#include "impeller/entity/gaussian_blur_alpha_decal.frag.h"
-#include "impeller/entity/gaussian_blur_alpha_nodecal.frag.h"
 #include "impeller/entity/gaussian_blur_noalpha_decal.frag.h"
 #include "impeller/entity/gaussian_blur_noalpha_nodecal.frag.h"
 
@@ -158,12 +156,6 @@ using PositionUVPipeline =
     RenderPipelineT<TextureFillVertexShader, TiledTextureFillFragmentShader>;
 using TiledTexturePipeline =
     RenderPipelineT<TextureFillVertexShader, TiledTextureFillFragmentShader>;
-using GaussianBlurAlphaDecalPipeline =
-    RenderPipelineT<GaussianBlurVertexShader,
-                    GaussianBlurAlphaDecalFragmentShader>;
-using GaussianBlurAlphaPipeline =
-    RenderPipelineT<GaussianBlurVertexShader,
-                    GaussianBlurAlphaNodecalFragmentShader>;
 using GaussianBlurDecalPipeline =
     RenderPipelineT<GaussianBlurVertexShader,
                     GaussianBlurNoalphaDecalFragmentShader>;
@@ -453,16 +445,6 @@ class ContentContext {
     return GetPipeline(tiled_texture_pipelines_, opts);
   }
 
-  std::shared_ptr<Pipeline<PipelineDescriptor>>
-  GetGaussianBlurAlphaDecalPipeline(ContentContextOptions opts) const {
-    return GetPipeline(gaussian_blur_alpha_decal_pipelines_, opts);
-  }
-
-  std::shared_ptr<Pipeline<PipelineDescriptor>> GetGaussianBlurAlphaPipeline(
-      ContentContextOptions opts) const {
-    return GetPipeline(gaussian_blur_alpha_nodecal_pipelines_, opts);
-  }
-
   std::shared_ptr<Pipeline<PipelineDescriptor>> GetGaussianBlurDecalPipeline(
       ContentContextOptions opts) const {
     return GetPipeline(gaussian_blur_noalpha_decal_pipelines_, opts);
@@ -772,10 +754,6 @@ class ContentContext {
 #endif  // IMPELLER_ENABLE_OPENGLES
   mutable Variants<PositionUVPipeline> position_uv_pipelines_;
   mutable Variants<TiledTexturePipeline> tiled_texture_pipelines_;
-  mutable Variants<GaussianBlurAlphaDecalPipeline>
-      gaussian_blur_alpha_decal_pipelines_;
-  mutable Variants<GaussianBlurAlphaPipeline>
-      gaussian_blur_alpha_nodecal_pipelines_;
   mutable Variants<GaussianBlurDecalPipeline>
       gaussian_blur_noalpha_decal_pipelines_;
   mutable Variants<GaussianBlurPipeline>

impeller/entity/contents/filters/filter_contents.cc

@@ -36,7 +36,7 @@ std::shared_ptr<FilterContents> FilterContents::MakeDirectionalGaussianBlur(
     Vector2 direction,
     BlurStyle blur_style,
     Entity::TileMode tile_mode,
-    FilterInput::Ref source_override,
+    bool is_second_pass,
     Sigma secondary_sigma,
     const Matrix& effect_transform) {
   auto blur = std::make_shared<DirectionalGaussianBlurFilterContents>();
@@ -45,7 +45,7 @@ std::shared_ptr<FilterContents> FilterContents::MakeDirectionalGaussianBlur(
   blur->SetDirection(direction);
   blur->SetBlurStyle(blur_style);
   blur->SetTileMode(tile_mode);
-  blur->SetSourceOverride(std::move(source_override));
+  blur->SetIsSecondPass(is_second_pass);
   blur->SetSecondarySigma(secondary_sigma);
   blur->SetEffectTransform(effect_transform);
   return blur;
@@ -60,10 +60,10 @@ std::shared_ptr<FilterContents> FilterContents::MakeGaussianBlur(
     const Matrix& effect_transform) {
   auto x_blur = MakeDirectionalGaussianBlur(input, sigma_x, Point(1, 0),
                                             BlurStyle::kNormal, tile_mode,
-                                            nullptr, {}, effect_transform);
+                                            false, {}, effect_transform);
   auto y_blur = MakeDirectionalGaussianBlur(FilterInput::Make(x_blur), sigma_y,
                                             Point(0, 1), blur_style, tile_mode,
-                                            input, sigma_x, effect_transform);
+                                            true, sigma_x, effect_transform);
   return y_blur;
 }
 

impeller/entity/contents/filters/filter_contents.h

@@ -37,7 +37,7 @@ class FilterContents : public Contents {
       Vector2 direction,
       BlurStyle blur_style = BlurStyle::kNormal,
       Entity::TileMode tile_mode = Entity::TileMode::kDecal,
-      FilterInput::Ref alpha_mask = nullptr,
+      bool is_second_pass = false,
       Sigma secondary_sigma = {},
       const Matrix& effect_transform = Matrix());
 

impeller/entity/contents/filters/gaussian_blur_filter_contents.cc

@@ -46,39 +46,16 @@ void DirectionalGaussianBlurFilterContents::SetDirection(Vector2 direction) {
 
 void DirectionalGaussianBlurFilterContents::SetBlurStyle(BlurStyle blur_style) {
   blur_style_ = blur_style;
-
-  switch (blur_style) {
-    case FilterContents::BlurStyle::kNormal:
-      src_color_factor_ = false;
-      inner_blur_factor_ = true;
-      outer_blur_factor_ = true;
-      break;
-    case FilterContents::BlurStyle::kSolid:
-      src_color_factor_ = true;
-      inner_blur_factor_ = false;
-      outer_blur_factor_ = true;
-      break;
-    case FilterContents::BlurStyle::kOuter:
-      src_color_factor_ = false;
-      inner_blur_factor_ = false;
-      outer_blur_factor_ = true;
-      break;
-    case FilterContents::BlurStyle::kInner:
-      src_color_factor_ = false;
-      inner_blur_factor_ = true;
-      outer_blur_factor_ = false;
-      break;
-  }
 }
 
 void DirectionalGaussianBlurFilterContents::SetTileMode(
     Entity::TileMode tile_mode) {
   tile_mode_ = tile_mode;
 }
 
-void DirectionalGaussianBlurFilterContents::SetSourceOverride(
-    FilterInput::Ref source_override) {
-  source_override_ = std::move(source_override);
+void DirectionalGaussianBlurFilterContents::SetIsSecondPass(
+    bool is_second_pass) {
+  is_second_pass_ = is_second_pass;
 }
 
 std::optional<Entity> DirectionalGaussianBlurFilterContents::RenderFilter(
@@ -88,10 +65,8 @@ std::optional<Entity> DirectionalGaussianBlurFilterContents::RenderFilter(
     const Matrix& effect_transform,
     const Rect& coverage,
     const std::optional<Rect>& coverage_hint) const {
-  using VS = GaussianBlurAlphaDecalPipeline::VertexShader;
-  using FS = GaussianBlurAlphaDecalPipeline::FragmentShader;
-
-  bool is_first_pass = !source_override_;
+  using VS = GaussianBlurPipeline::VertexShader;
+  using FS = GaussianBlurPipeline::FragmentShader;
 
   //----------------------------------------------------------------------------
   /// Handle inputs.
@@ -118,9 +93,9 @@ std::optional<Entity> DirectionalGaussianBlurFilterContents::RenderFilter(
         Size(transformed_blur_radius_length, transformed_blur_radius_length)
             .Abs();
     expanded_coverage_hint =
-        is_first_pass ? Rect(coverage_hint.value().origin - r,
-                             Size(coverage_hint.value().size + r * 2))
-                      : coverage_hint;
+        is_second_pass_ ? coverage_hint
+                        : Rect(coverage_hint.value().origin - r,
+                               Size(coverage_hint.value().size + r * 2));
   }
   auto input_snapshot = inputs[0]->GetSnapshot("GaussianBlur", renderer, entity,
                                                expanded_coverage_hint);
@@ -160,15 +135,6 @@ std::optional<Entity> DirectionalGaussianBlurFilterContents::RenderFilter(
   pass_texture_rect.origin.x -= transformed_blur_radius_length;
   pass_texture_rect.size.width += transformed_blur_radius_length * 2;
 
-  // Source override snapshot.
-
-  auto source = source_override_ ? source_override_ : inputs[0];
-  auto source_snapshot = source->GetSnapshot("GaussianBlur(Override)", renderer,
-                                             entity, GetCoverageHint());
-  if (!source_snapshot.has_value()) {
-    return std::nullopt;
-  }
-
   // UV mapping.
 
   auto pass_uv_project = [&texture_rotate,
@@ -180,8 +146,6 @@ std::optional<Entity> DirectionalGaussianBlurFilterContents::RenderFilter(
 
   auto input_uvs = pass_uv_project(input_snapshot.value());
 
-  auto source_uvs = pass_uv_project(source_snapshot.value());
-
   //----------------------------------------------------------------------------
   /// Render to texture.
   ///
@@ -193,21 +157,19 @@ std::optional<Entity> DirectionalGaussianBlurFilterContents::RenderFilter(
 
     VertexBufferBuilder<VS::PerVertexData> vtx_builder;
     vtx_builder.AddVertices({
-        {Point(0, 0), input_uvs[0], source_uvs[0]},
-        {Point(1, 0), input_uvs[1], source_uvs[1]},
-        {Point(1, 1), input_uvs[3], source_uvs[3]},
-        {Point(0, 0), input_uvs[0], source_uvs[0]},
-        {Point(1, 1), input_uvs[3], source_uvs[3]},
-        {Point(0, 1), input_uvs[2], source_uvs[2]},
+        {Point(0, 0), input_uvs[0]},
+        {Point(1, 0), input_uvs[1]},
+        {Point(1, 1), input_uvs[3]},
+        {Point(0, 0), input_uvs[0]},
+        {Point(1, 1), input_uvs[3]},
+        {Point(0, 1), input_uvs[2]},
     });
     auto vtx_buffer = vtx_builder.CreateVertexBuffer(host_buffer);
 
     VS::FrameInfo frame_info;
     frame_info.mvp = Matrix::MakeOrthographic(ISize(1, 1));
     frame_info.texture_sampler_y_coord_scale =
         input_snapshot->texture->GetYCoordScale();
-    frame_info.alpha_mask_sampler_y_coord_scale =
-        source_snapshot->texture->GetYCoordScale();
 
     FS::BlurInfo frag_info;
     auto r = Radius{transformed_blur_radius_length};
@@ -227,50 +189,35 @@ std::optional<Entity> DirectionalGaussianBlurFilterContents::RenderFilter(
     auto options = OptionsFromPass(pass);
     options.blend_mode = BlendMode::kSource;
     auto input_descriptor = input_snapshot->sampler_descriptor;
-    auto source_descriptor = source_snapshot->sampler_descriptor;
     switch (tile_mode_) {
       case Entity::TileMode::kDecal:
         if (renderer.GetDeviceCapabilities()
                 .SupportsDecalSamplerAddressMode()) {
           input_descriptor.width_address_mode = SamplerAddressMode::kDecal;
           input_descriptor.height_address_mode = SamplerAddressMode::kDecal;
-          source_descriptor.width_address_mode = SamplerAddressMode::kDecal;
-          source_descriptor.height_address_mode = SamplerAddressMode::kDecal;
         }
         break;
       case Entity::TileMode::kClamp:
         input_descriptor.width_address_mode = SamplerAddressMode::kClampToEdge;
         input_descriptor.height_address_mode = SamplerAddressMode::kClampToEdge;
-        source_descriptor.width_address_mode = SamplerAddressMode::kClampToEdge;
-        source_descriptor.height_address_mode =
-            SamplerAddressMode::kClampToEdge;
         break;
       case Entity::TileMode::kMirror:
         input_descriptor.width_address_mode = SamplerAddressMode::kMirror;
         input_descriptor.height_address_mode = SamplerAddressMode::kMirror;
-        source_descriptor.width_address_mode = SamplerAddressMode::kMirror;
-        source_descriptor.height_address_mode = SamplerAddressMode::kMirror;
         break;
       case Entity::TileMode::kRepeat:
         input_descriptor.width_address_mode = SamplerAddressMode::kRepeat;
         input_descriptor.height_address_mode = SamplerAddressMode::kRepeat;
-        source_descriptor.width_address_mode = SamplerAddressMode::kRepeat;
-        source_descriptor.height_address_mode = SamplerAddressMode::kRepeat;
         break;
     }
     input_descriptor.mag_filter = MinMagFilter::kLinear;
     input_descriptor.min_filter = MinMagFilter::kLinear;
 
-    bool has_alpha_mask = blur_style_ != BlurStyle::kNormal;
     bool has_decal_specialization =
         tile_mode_ == Entity::TileMode::kDecal &&
         !renderer.GetDeviceCapabilities().SupportsDecalSamplerAddressMode();
 
-    if (has_alpha_mask && has_decal_specialization) {
-      cmd.pipeline = renderer.GetGaussianBlurAlphaDecalPipeline(options);
-    } else if (has_alpha_mask) {
-      cmd.pipeline = renderer.GetGaussianBlurAlphaPipeline(options);
-    } else if (has_decal_specialization) {
+    if (has_decal_specialization) {
       cmd.pipeline = renderer.GetGaussianBlurDecalPipeline(options);
     } else {
       cmd.pipeline = renderer.GetGaussianBlurPipeline(options);
@@ -283,19 +230,6 @@ std::optional<Entity> DirectionalGaussianBlurFilterContents::RenderFilter(
     VS::BindFrameInfo(cmd, host_buffer.EmplaceUniform(frame_info));
     FS::BindBlurInfo(cmd, host_buffer.EmplaceUniform(frag_info));
 
-    if (has_alpha_mask) {
-      FS::MaskInfo mask_info;
-      mask_info.src_factor = src_color_factor_;
-      mask_info.inner_blur_factor = inner_blur_factor_;
-      mask_info.outer_blur_factor = outer_blur_factor_;
-
-      FS::BindAlphaMaskSampler(
-          cmd, source_snapshot->texture,
-          renderer.GetContext()->GetSamplerLibrary()->GetSampler(
-              source_descriptor));
-      FS::BindMaskInfo(cmd, host_buffer.EmplaceUniform(mask_info));
-    }
-
     return pass.AddCommand(std::move(cmd));
   };
 
@@ -310,8 +244,8 @@ std::optional<Entity> DirectionalGaussianBlurFilterContents::RenderFilter(
   {
     scale.x = scale_curve(transformed_blur_radius_length);
 
-    Scalar y_radius = std::abs(pass_transform.GetDirectionScale(
-        Vector2(0, !is_first_pass ? Radius{secondary_blur_sigma_}.radius : 1)));
+    Scalar y_radius = std::abs(pass_transform.GetDirectionScale(Vector2(
+        0, !is_second_pass_ ? 1 : Radius{secondary_blur_sigma_}.radius)));
     scale.y = scale_curve(y_radius);
   }
 

impeller/entity/contents/filters/gaussian_blur_filter_contents.h

@@ -27,7 +27,7 @@ class DirectionalGaussianBlurFilterContents final : public FilterContents {
 
   void SetTileMode(Entity::TileMode tile_mode);
 
-  void SetSourceOverride(FilterInput::Ref alpha_mask);
+  void SetIsSecondPass(bool is_second_pass);
 
   // |FilterContents|
   std::optional<Rect> GetFilterCoverage(
@@ -49,10 +49,7 @@ class DirectionalGaussianBlurFilterContents final : public FilterContents {
   Vector2 blur_direction_;
   BlurStyle blur_style_ = BlurStyle::kNormal;
   Entity::TileMode tile_mode_ = Entity::TileMode::kDecal;
-  bool src_color_factor_ = false;
-  bool inner_blur_factor_ = true;
-  bool outer_blur_factor_ = true;
-  FilterInput::Ref source_override_;
+  bool is_second_pass_ = false;
 
   FML_DISALLOW_COPY_AND_ASSIGN(DirectionalGaussianBlurFilterContents);
 };

impeller/entity/shaders/gaussian_blur/gaussian_blur.glsl

@@ -32,17 +32,6 @@ uniform BlurInfo {
 }
 blur_info;
 
-#if ENABLE_ALPHA_MASK
-uniform f16sampler2D alpha_mask_sampler;
-
-uniform MaskInfo {
-  float16_t src_factor;
-  float16_t inner_blur_factor;
-  float16_t outer_blur_factor;
-}
-mask_info;
-#endif
-
 f16vec4 Sample(f16sampler2D tex, vec2 coords) {
 #if ENABLE_DECAL_SPECIALIZATION
   return IPHalfSampleDecal(tex, coords);
@@ -76,19 +65,4 @@ void main() {
   }
 
   frag_color = total_color / gaussian_integral;
-
-#if ENABLE_ALPHA_MASK
-  f16vec4 src_color = Sample(alpha_mask_sampler,   // sampler
-                             v_src_texture_coords  // texture coordinates
-  );
-
-  float16_t blur_factor;
-  if (src_color.a > 0.0hf) {
-    blur_factor = mask_info.inner_blur_factor;
-  } else if (src_color.a == 0.0hf) {
-    blur_factor = mask_info.outer_blur_factor;
-  }
-
-  frag_color = frag_color * blur_factor + src_color * mask_info.src_factor;
-#endif
 }