++

impeller/aiks/canvas.cc

@@ -926,16 +926,16 @@ void Canvas::DrawVertices(const std::shared_ptr<VerticesGeometry>& vertices,
   entity.SetTransform(GetCurrentTransform());
   entity.SetBlendMode(paint.blend_mode);
 
-  // If there are no vertex color or texture coordinates.
+  // If there are no vertex colors.
   if (UseColorSourceContents(vertices, paint)) {
     entity.SetContents(CreateContentsForGeometryWithFilters(paint, vertices));
     AddRenderEntityToCurrentPass(std::move(entity));
     return;
   }
 
-  // If there is are per-vertex colors, an image, and the blend mode
-  // is simple we can draw without a sub-renderpass.
-  if (blend_mode <= BlendMode::kModulate && vertices->HasVertexColors()) {
+  // If there is an image, and the blend mode is simple we can draw without a
+  // sub-renderpass. per-vertex colors aren't required but are supported.
+  if (blend_mode <= BlendMode::kModulate) {
     if (std::optional<ImageData> maybe_image_data =
             GetImageColorSourceData(paint.color_source)) {
       const ImageData& image_data = maybe_image_data.value();

impeller/entity/contents/vertices_contents.cc

@@ -275,7 +275,6 @@ bool VerticesSimpleBlendContents::Render(const ContentContext& renderer,
                                          const Entity& entity,
                                          RenderPass& pass) const {
   FML_DCHECK(texture_);
-  FML_DCHECK(geometry_->HasVertexColors());
 
   // Simple Porter-Duff blends can be accomplished without a sub renderpass.
   using VS = PorterDuffBlendPipeline::VertexShader;
@@ -319,8 +318,11 @@ bool VerticesSimpleBlendContents::Render(const ContentContext& renderer,
   frag_info.output_alpha = alpha_;
   frag_info.input_alpha = 1.0;
 
-  auto inverted_blend_mode =
+  BlendMode inverted_blend_mode =
       InvertPorterDuffBlend(blend_mode_).value_or(BlendMode::kSource);
+  if (geometry_->HasVertexColors()) {
+    inverted_blend_mode = BlendMode::kSource;
+  }
   auto blend_coefficients =
       kPorterDuffCoefficients[static_cast<int>(inverted_blend_mode)];
   frag_info.src_coeff = blend_coefficients[0];

impeller/entity/geometry/vertices_geometry.cc

@@ -9,6 +9,7 @@
 
 #include "impeller/core/buffer_view.h"
 #include "impeller/entity/contents/content_context.h"
+#include "impeller/geometry/color.h"
 
 namespace impeller {
 
@@ -256,6 +257,7 @@ GeometryResult VerticesGeometry::GetPositionUVColorBuffer(
   auto uv_transform =
       texture_coverage.GetNormalizingTransform() * effect_transform;
   auto has_texture_coordinates = HasTextureCoordinates();
+  auto has_colors = HasVertexColors();
 
   size_t total_vtx_bytes = vertices_.size() * sizeof(VS::PerVertexData);
   auto vertex_buffer = renderer.GetTransientsBuffer().Emplace(
@@ -274,8 +276,7 @@ GeometryResult VerticesGeometry::GetPositionUVColorBuffer(
               .texture_coords =
                   Point(std::clamp(uv.x, 0.0f, 1.0f - kEhCloseEnough),
                         std::clamp(uv.y, 0.0f, 1.0f - kEhCloseEnough)),
-              .color = colors_[i],
-          };
+              .color = has_colors ? colors_[i] : Color::BlackTransparent()};
           std::memcpy(vtx_contents++, &vertex_data, sizeof(VS::PerVertexData));
         }
       });