Simplify SpanBuffer

Author: knopp

display_list/benchmarking/dl_region_benchmarks.cc

@@ -13,8 +13,6 @@ namespace {
 
 class SkRegionAdapter {
  public:
-  SkRegionAdapter() {}
-
   explicit SkRegionAdapter(const std::vector<SkIRect>& rects) {
     for (const auto& rect : rects) {
       region_.op(rect, SkRegion::kUnion_Op);
@@ -23,8 +21,11 @@ class SkRegionAdapter {
 
   SkIRect getBounds() { return region_.getBounds(); }
 
-  void addRegion(const SkRegionAdapter& region) {
-    region_.op(region.region_, SkRegion::kUnion_Op);
+  static SkRegionAdapter unionRegions(const SkRegionAdapter& a1,
+                                      const SkRegionAdapter& a2) {
+    SkRegionAdapter result(a1);
+    result.region_.op(a2.region_, SkRegion::kUnion_Op);
+    return result;
   }
 
   bool intersects(const SkRegionAdapter& region) {
@@ -49,13 +50,13 @@ class SkRegionAdapter {
 
 class DlRegionAdapter {
  public:
-  DlRegionAdapter() {}
-
   explicit DlRegionAdapter(const std::vector<SkIRect>& rects)
       : region_(rects) {}
 
-  void addRegion(const DlRegionAdapter& region) {
-    region_.addRegion(region.region_);
+  static DlRegionAdapter unionRegions(const DlRegionAdapter& a1,
+                                      const DlRegionAdapter& a2) {
+    return DlRegionAdapter(
+        flutter::DlRegion::MakeUnion(a1.region_, a2.region_));
   }
 
   SkIRect getBounds() { return region_.bounds(); }
@@ -68,9 +69,10 @@ class DlRegionAdapter {
 
   std::vector<SkIRect> getRects() { return region_.getRects(false); }
 
-  DlRegionAdapter(const DlRegionAdapter& copy) : region_(copy.region_, true) {}
-
  private:
+  explicit DlRegionAdapter(flutter::DlRegion&& region)
+      : region_(std::move(region)) {}
+
   flutter::DlRegion region_;
 };
 
@@ -120,10 +122,7 @@ void RunAddRegionBenchmark(benchmark::State& state, int maxSize) {
   Region region2(rects);
 
   while (state.KeepRunning()) {
-    Region copy_of_region1(region1);
-    copy_of_region1.addRegion(region2);
-    // Region copy_of_region2(region2);
-    // copy_of_region2.addRegion(region1);
+    Region::unionRegions(region1, region2);
   }
 }