Delete Settings::msaa_samples.

Fixes flutter/flutter#148257

Author: chinmaygarde

common/graphics/BUILD.gn

@@ -10,7 +10,6 @@ source_set("graphics") {
   sources = [
     "gl_context_switch.cc",
     "gl_context_switch.h",
-    "msaa_sample_count.h",
     "persistent_cache.cc",
     "persistent_cache.h",
     "texture.cc",

common/graphics/msaa_sample_count.h

@@ -348,13 +348,6 @@ struct Settings {
   // Max bytes threshold of resource cache, or 0 for unlimited.
   size_t resource_cache_max_bytes_threshold = 0;
 
-  /// The minimum number of samples to require in multipsampled anti-aliasing.
-  ///
-  /// Setting this value to 0 or 1 disables MSAA.
-  /// If it is not 0 or 1, it must be one of 2, 4, 8, or 16. However, if the
-  /// GPU does not support the requested sampling value, MSAA will be disabled.
-  uint8_t msaa_samples = 0;
-
   /// Enable embedder api on the embedder.
   ///
   /// This is currently only used by iOS.

common/settings.h

@@ -116,8 +116,7 @@ GPUMTLTextureInfo offscreen_texture_info() const {
     return std::make_unique<GPUSurfaceMetalImpeller>(this,
                                                      [metal_context_->impeller_context() context]);
   }
-  return std::make_unique<GPUSurfaceMetalSkia>(this, [metal_context_->context() mainContext],
-                                               MsaaSampleCount::kNone);
+  return std::make_unique<GPUSurfaceMetalSkia>(this, [metal_context_->context() mainContext]);
 }
 
 // |PlatformView|

shell/common/shell_test_platform_view_metal.mm

@@ -519,28 +519,6 @@ Settings SettingsFromCommandLine(const fml::CommandLine& command_line) {
         std::stoi(resource_cache_max_bytes_threshold);
   }
 
-  if (command_line.HasOption(FlagForSwitch(Switch::MsaaSamples))) {
-    std::string msaa_samples;
-    command_line.GetOptionValue(FlagForSwitch(Switch::MsaaSamples),
-                                &msaa_samples);
-    if (msaa_samples == "0") {
-      settings.msaa_samples = 0;
-    } else if (msaa_samples == "1") {
-      settings.msaa_samples = 1;
-    } else if (msaa_samples == "2") {
-      settings.msaa_samples = 2;
-    } else if (msaa_samples == "4") {
-      settings.msaa_samples = 4;
-    } else if (msaa_samples == "8") {
-      settings.msaa_samples = 8;
-    } else if (msaa_samples == "16") {
-      settings.msaa_samples = 16;
-    } else {
-      FML_DLOG(ERROR) << "Invalid value for --msaa-samples: '" << msaa_samples
-                      << "' (expected 0, 1, 2, 4, 8, or 16).";
-    }
-  }
-
   settings.enable_platform_isolates =
       command_line.HasOption(FlagForSwitch(Switch::EnablePlatformIsolates));
 

shell/common/switches.cc

@@ -288,13 +288,6 @@ DEF_SWITCH(LeakVM,
            "When the last shell shuts down, the shared VM is leaked by default "
            "(the leak_vm in VM settings is true). To clean up the leak VM, set "
            "this value to false.")
-DEF_SWITCH(
-    MsaaSamples,
-    "msaa-samples",
-    "The minimum number of samples to require for multisampled anti-aliasing.  "
-    "Setting this value to 0 or 1 disables MSAA. If it is not 0 or 1, it must "
-    "be one of 2, 4, 8, or 16. However, if the GPU does not support the "
-    "requested sampling value, MSAA will be disabled.")
 DEF_SWITCH(EnableEmbedderAPI,
            "enable-embedder-api",
            "Enable the embedder api. Defaults to false. iOS only.")

shell/common/switches.h

@@ -69,24 +69,6 @@ TEST(SwitchesTest, RouteParsedFlag) {
   EXPECT_TRUE(settings.route.empty());
 }
 
-TEST(SwitchesTest, MsaaSamples) {
-  for (int samples : {0, 1, 2, 4, 8, 16}) {
-    fml::CommandLine command_line = fml::CommandLineFromInitializerList(
-        {"command", ("--msaa-samples=" + std::to_string(samples)).c_str()});
-    Settings settings = SettingsFromCommandLine(command_line);
-    EXPECT_EQ(settings.msaa_samples, samples);
-  }
-  fml::CommandLine command_line =
-      fml::CommandLineFromInitializerList({"command", "--msaa-samples=3"});
-  Settings settings = SettingsFromCommandLine(command_line);
-  EXPECT_EQ(settings.msaa_samples, 0);
-
-  command_line =
-      fml::CommandLineFromInitializerList({"command", "--msaa-samples=foobar"});
-  settings = SettingsFromCommandLine(command_line);
-  EXPECT_EQ(settings.msaa_samples, 0);
-}
-
 TEST(SwitchesTest, EnableEmbedderAPI) {
   {
     // enable

shell/common/switches_unittests.cc

@@ -5,7 +5,6 @@
 #ifndef FLUTTER_SHELL_GPU_GPU_SURFACE_METAL_SKIA_H_
 #define FLUTTER_SHELL_GPU_GPU_SURFACE_METAL_SKIA_H_
 
-#include "flutter/common/graphics/msaa_sample_count.h"
 #include "flutter/flow/surface.h"
 #include "flutter/fml/macros.h"
 #include "flutter/shell/gpu/gpu_surface_metal_delegate.h"
@@ -17,7 +16,6 @@ class SK_API_AVAILABLE_CA_METAL_LAYER GPUSurfaceMetalSkia : public Surface {
  public:
   GPUSurfaceMetalSkia(GPUSurfaceMetalDelegate* delegate,
                       sk_sp<GrDirectContext> context,
-                      MsaaSampleCount msaa_samples,
                       bool render_to_surface = true);
 
   // |Surface|
@@ -31,7 +29,6 @@ class SK_API_AVAILABLE_CA_METAL_LAYER GPUSurfaceMetalSkia : public Surface {
   const MTLRenderTargetType render_target_type_;
   sk_sp<GrDirectContext> context_;
   GrDirectContext* precompiled_sksl_context_ = nullptr;
-  MsaaSampleCount msaa_samples_ = MsaaSampleCount::kNone;
   // TODO(38466): Refactor GPU surface APIs take into account the fact that an
   // external view embedder may want to render to the root surface. This is a
   // hack to make avoid allocating resources for the root surface when an

shell/gpu/gpu_surface_metal_skia.h

@@ -39,7 +39,6 @@
 sk_sp<SkSurface> CreateSurfaceFromMetalTexture(GrDirectContext* context,
                                                id<MTLTexture> texture,
                                                GrSurfaceOrigin origin,
-                                               MsaaSampleCount sample_cnt,
                                                SkColorType color_type,
                                                sk_sp<SkColorSpace> color_space,
                                                const SkSurfaceProps* props,
@@ -49,20 +48,18 @@
   info.fTexture.reset([texture retain]);
   GrBackendTexture backend_texture =
       GrBackendTextures::MakeMtl(texture.width, texture.height, skgpu::Mipmapped::kNo, info);
-  return SkSurfaces::WrapBackendTexture(
-      context, backend_texture, origin, static_cast<int>(sample_cnt), color_type,
-      std::move(color_space), props, release_proc, release_context);
+  return SkSurfaces::WrapBackendTexture(context, backend_texture, origin, 1, color_type,
+                                        std::move(color_space), props, release_proc,
+                                        release_context);
 }
 }  // namespace
 
 GPUSurfaceMetalSkia::GPUSurfaceMetalSkia(GPUSurfaceMetalDelegate* delegate,
                                          sk_sp<GrDirectContext> context,
-                                         MsaaSampleCount msaa_samples,
                                          bool render_to_surface)
     : delegate_(delegate),
       render_target_type_(delegate->GetRenderTargetType()),
       context_(std::move(context)),
-      msaa_samples_(msaa_samples),
       render_to_surface_(render_to_surface) {
   // If this preference is explicitly set, we allow for disabling partial repaint.
   NSNumber* disablePartialRepaint =
@@ -141,7 +138,6 @@
 
   auto surface = CreateSurfaceFromMetalTexture(context_.get(), drawable.get().texture,
                                                kTopLeft_GrSurfaceOrigin,  // origin
-                                               msaa_samples_,             // sample count
                                                kBGRA_8888_SkColorType,    // color type
                                                nullptr,                   // colorspace
                                                nullptr,                   // surface properties
@@ -213,8 +209,8 @@
   }
 
   sk_sp<SkSurface> surface = CreateSurfaceFromMetalTexture(
-      context_.get(), mtl_texture, kTopLeft_GrSurfaceOrigin, msaa_samples_, kBGRA_8888_SkColorType,
-      nullptr, nullptr, static_cast<SkSurfaces::TextureReleaseProc>(texture.destruction_callback),
+      context_.get(), mtl_texture, kTopLeft_GrSurfaceOrigin, kBGRA_8888_SkColorType, nullptr,
+      nullptr, static_cast<SkSurfaces::TextureReleaseProc>(texture.destruction_callback),
       texture.destruction_context);
 
   if (!surface) {

shell/gpu/gpu_surface_metal_skia.mm

@@ -24,9 +24,7 @@ static EGLResult<EGLContext> CreateContext(EGLDisplay display,
   return {context != EGL_NO_CONTEXT, context};
 }
 
-static EGLResult<EGLConfig> ChooseEGLConfiguration(EGLDisplay display,
-                                                   uint8_t msaa_samples) {
-  EGLint sample_buffers = msaa_samples > 1 ? 1 : 0;
+static EGLResult<EGLConfig> ChooseEGLConfiguration(EGLDisplay display) {
   EGLint attributes[] = {
       // clang-format off
       EGL_RENDERABLE_TYPE, EGL_OPENGL_ES2_BIT,
@@ -37,8 +35,6 @@ static EGLResult<EGLConfig> ChooseEGLConfiguration(EGLDisplay display,
       EGL_ALPHA_SIZE,      8,
       EGL_DEPTH_SIZE,      0,
       EGL_STENCIL_SIZE,    0,
-      EGL_SAMPLES,         static_cast<EGLint>(msaa_samples),
-      EGL_SAMPLE_BUFFERS,  sample_buffers,
       EGL_NONE,            // termination sentinel
       // clang-format on
   };
@@ -66,8 +62,7 @@ static bool TeardownContext(EGLDisplay display, EGLContext context) {
 
 AndroidContextGLSkia::AndroidContextGLSkia(
     fml::RefPtr<AndroidEnvironmentGL> environment,
-    const TaskRunners& task_runners,
-    uint8_t msaa_samples)
+    const TaskRunners& task_runners)
     : AndroidContext(AndroidRenderingAPI::kSkiaOpenGLES),
       environment_(std::move(environment)),
       task_runners_(task_runners) {
@@ -79,8 +74,7 @@ AndroidContextGLSkia::AndroidContextGLSkia(
   bool success = false;
 
   // Choose a valid configuration.
-  std::tie(success, config_) =
-      ChooseEGLConfiguration(environment_->Display(), msaa_samples);
+  std::tie(success, config_) = ChooseEGLConfiguration(environment_->Display());
   if (!success) {
     FML_LOG(ERROR) << "Could not choose an EGL configuration.";
     LogLastEGLError();