[Impeller] moved tests to aiks_blur_unittests, added warning (#51274)

issue: flutter/flutter#140106

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Author: gaaclarke

impeller/aiks/aiks_blur_unittests.cc

@@ -5,6 +5,7 @@
 #include "flutter/impeller/aiks/aiks_unittests.h"
 
 #include "impeller/aiks/canvas.h"
+#include "impeller/entity/contents/filters/gaussian_blur_filter_contents.h"
 #include "impeller/entity/render_target_cache.h"
 #include "impeller/geometry/path_builder.h"
 #include "impeller/playground/widgets.h"
@@ -672,5 +673,187 @@ TEST_P(AiksTest, GaussianBlurStyleSolid) {
   ASSERT_TRUE(OpenPlaygroundHere(canvas.EndRecordingAsPicture()));
 }
 
+TEST_P(AiksTest, GuassianBlurUpdatesMipmapContents) {
+  // This makes sure if mip maps are recycled across invocations of blurs the
+  // contents get updated each frame correctly. If they aren't updated the color
+  // inside the blur and outside the blur will be different.
+  //
+  // If there is some change to render target caching this could display a false
+  // positive in the future.  Also, if the LOD that is rendered is 1 it could
+  // present a false positive.
+  int32_t count = 0;
+  auto callback = [&](AiksContext& renderer) -> std::optional<Picture> {
+    Canvas canvas;
+    if (count++ == 0) {
+      canvas.DrawCircle({100, 100}, 50, {.color = Color::CornflowerBlue()});
+    } else {
+      canvas.DrawCircle({100, 100}, 50, {.color = Color::Chartreuse()});
+    }
+    canvas.ClipRRect(Rect::MakeLTRB(75, 50, 375, 275), {20, 20});
+    canvas.SaveLayer({.blend_mode = BlendMode::kSource}, std::nullopt,
+                     ImageFilter::MakeBlur(Sigma(30.0), Sigma(30.0),
+                                           FilterContents::BlurStyle::kNormal,
+                                           Entity::TileMode::kClamp));
+    canvas.Restore();
+    return canvas.EndRecordingAsPicture();
+  };
+
+  ASSERT_TRUE(OpenPlaygroundHere(callback));
+}
+
+TEST_P(AiksTest, GaussianBlurSetsMipCountOnPass) {
+  Canvas canvas;
+  canvas.DrawCircle({100, 100}, 50, {.color = Color::CornflowerBlue()});
+  canvas.SaveLayer({}, std::nullopt,
+                   ImageFilter::MakeBlur(Sigma(3), Sigma(3),
+                                         FilterContents::BlurStyle::kNormal,
+                                         Entity::TileMode::kClamp));
+  canvas.Restore();
+
+  Picture picture = canvas.EndRecordingAsPicture();
+  EXPECT_EQ(4, picture.pass->GetRequiredMipCount());
+}
+
+TEST_P(AiksTest, GaussianBlurAllocatesCorrectMipCountRenderTarget) {
+  size_t blur_required_mip_count =
+      GetParam() == PlaygroundBackend::kOpenGLES ? 1 : 4;
+
+  Canvas canvas;
+  canvas.DrawCircle({100, 100}, 50, {.color = Color::CornflowerBlue()});
+  canvas.SaveLayer({}, std::nullopt,
+                   ImageFilter::MakeBlur(Sigma(3), Sigma(3),
+                                         FilterContents::BlurStyle::kNormal,
+                                         Entity::TileMode::kClamp));
+  canvas.Restore();
+
+  Picture picture = canvas.EndRecordingAsPicture();
+  std::shared_ptr<RenderTargetCache> cache =
+      std::make_shared<RenderTargetCache>(GetContext()->GetResourceAllocator());
+  AiksContext aiks_context(GetContext(), nullptr, cache);
+  picture.ToImage(aiks_context, {100, 100});
+
+  size_t max_mip_count = 0;
+  for (auto it = cache->GetRenderTargetDataBegin();
+       it != cache->GetRenderTargetDataEnd(); ++it) {
+    max_mip_count = std::max(it->config.mip_count, max_mip_count);
+  }
+  EXPECT_EQ(max_mip_count, blur_required_mip_count);
+}
+
+TEST_P(AiksTest, GaussianBlurMipMapNestedLayer) {
+  fml::testing::LogCapture log_capture;
+  size_t blur_required_mip_count =
+      GetParam() == PlaygroundBackend::kOpenGLES ? 1 : 4;
+
+  Canvas canvas;
+  canvas.DrawPaint({.color = Color::Wheat()});
+  canvas.SaveLayer({.blend_mode = BlendMode::kMultiply});
+  canvas.DrawCircle({100, 100}, 50, {.color = Color::CornflowerBlue()});
+  canvas.SaveLayer({}, std::nullopt,
+                   ImageFilter::MakeBlur(Sigma(30), Sigma(30),
+                                         FilterContents::BlurStyle::kNormal,
+                                         Entity::TileMode::kClamp));
+  canvas.DrawCircle({200, 200}, 50, {.color = Color::Chartreuse()});
+
+  Picture picture = canvas.EndRecordingAsPicture();
+  std::shared_ptr<RenderTargetCache> cache =
+      std::make_shared<RenderTargetCache>(GetContext()->GetResourceAllocator());
+  AiksContext aiks_context(GetContext(), nullptr, cache);
+  picture.ToImage(aiks_context, {100, 100});
+
+  size_t max_mip_count = 0;
+  for (auto it = cache->GetRenderTargetDataBegin();
+       it != cache->GetRenderTargetDataEnd(); ++it) {
+    max_mip_count = std::max(it->config.mip_count, max_mip_count);
+  }
+  EXPECT_EQ(max_mip_count, blur_required_mip_count);
+  // The log is FML_DLOG, so only check in debug builds.
+#ifndef NDEBUG
+  if (GetParam() != PlaygroundBackend::kOpenGLES) {
+    EXPECT_EQ(log_capture.str().find(GaussianBlurFilterContents::kNoMipsError),
+              std::string::npos);
+  } else {
+    EXPECT_NE(log_capture.str().find(GaussianBlurFilterContents::kNoMipsError),
+              std::string::npos);
+  }
+#endif
+}
+
+TEST_P(AiksTest, GaussianBlurMipMapImageFilter) {
+  size_t blur_required_mip_count =
+      GetParam() == PlaygroundBackend::kOpenGLES ? 1 : 4;
+  fml::testing::LogCapture log_capture;
+  Canvas canvas;
+  canvas.SaveLayer(
+      {.image_filter = ImageFilter::MakeBlur(Sigma(30), Sigma(30),
+                                             FilterContents::BlurStyle::kNormal,
+                                             Entity::TileMode::kClamp)});
+  canvas.DrawCircle({200, 200}, 50, {.color = Color::Chartreuse()});
+
+  Picture picture = canvas.EndRecordingAsPicture();
+  std::shared_ptr<RenderTargetCache> cache =
+      std::make_shared<RenderTargetCache>(GetContext()->GetResourceAllocator());
+  AiksContext aiks_context(GetContext(), nullptr, cache);
+  picture.ToImage(aiks_context, {1024, 768});
+
+  size_t max_mip_count = 0;
+  for (auto it = cache->GetRenderTargetDataBegin();
+       it != cache->GetRenderTargetDataEnd(); ++it) {
+    max_mip_count = std::max(it->config.mip_count, max_mip_count);
+  }
+  EXPECT_EQ(max_mip_count, blur_required_mip_count);
+  // The log is FML_DLOG, so only check in debug builds.
+#ifndef NDEBUG
+  if (GetParam() != PlaygroundBackend::kOpenGLES) {
+    EXPECT_EQ(log_capture.str().find(GaussianBlurFilterContents::kNoMipsError),
+              std::string::npos);
+  } else {
+    EXPECT_NE(log_capture.str().find(GaussianBlurFilterContents::kNoMipsError),
+              std::string::npos);
+  }
+#endif
+}
+
+TEST_P(AiksTest, GaussianBlurMipMapSolidColor) {
+  size_t blur_required_mip_count =
+      GetParam() == PlaygroundBackend::kOpenGLES ? 1 : 4;
+  fml::testing::LogCapture log_capture;
+  Canvas canvas;
+  canvas.DrawPath(PathBuilder{}
+                      .MoveTo({100, 100})
+                      .LineTo({200, 100})
+                      .LineTo({150, 200})
+                      .LineTo({50, 200})
+                      .Close()
+                      .TakePath(),
+                  {.color = Color::Chartreuse(),
+                   .image_filter = ImageFilter::MakeBlur(
+                       Sigma(30), Sigma(30), FilterContents::BlurStyle::kNormal,
+                       Entity::TileMode::kClamp)});
+
+  Picture picture = canvas.EndRecordingAsPicture();
+  std::shared_ptr<RenderTargetCache> cache =
+      std::make_shared<RenderTargetCache>(GetContext()->GetResourceAllocator());
+  AiksContext aiks_context(GetContext(), nullptr, cache);
+  picture.ToImage(aiks_context, {1024, 768});
+
+  size_t max_mip_count = 0;
+  for (auto it = cache->GetRenderTargetDataBegin();
+       it != cache->GetRenderTargetDataEnd(); ++it) {
+    max_mip_count = std::max(it->config.mip_count, max_mip_count);
+  }
+  EXPECT_EQ(max_mip_count, blur_required_mip_count);
+  // The log is FML_DLOG, so only check in debug builds.
+#ifndef NDEBUG
+  if (GetParam() != PlaygroundBackend::kOpenGLES) {
+    EXPECT_EQ(log_capture.str().find(GaussianBlurFilterContents::kNoMipsError),
+              std::string::npos);
+  } else {
+    EXPECT_NE(log_capture.str().find(GaussianBlurFilterContents::kNoMipsError),
+              std::string::npos);
+  }
+#endif
+}
+
 }  // namespace testing
 }  // namespace impeller