Keep track of the number of skia operations

src/core/SkPictureContentInfo.cpp

Index: src/core/SkPictureContentInfo.cpp
diff --git a/src/core/SkPictureContentInfo.cpp b/src/core/SkPictureContentInfo.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..8185d850b8d9b0b81f1c97a2dfe7d4819ab21663
--- /dev/null
+++ b/src/core/SkPictureContentInfo.cpp
@@ -0,0 +1,99 @@
+/*
+ * Copyright 2014 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include "SkPaint.h"
+#include "SkPathEffect.h"
+#include "SkPictureContentInfo.h"
+
+bool SkPictureContentInfo::suitableForGpuRasterization(GrContext* context, const char **reason,
+                                                       int sampleCount) const {
+    // TODO: the heuristic used here needs to be refined
+    static const int kNumPaintWithPathEffectUsesTol = 1;
+    static const int kNumAAConcavePaths = 5;
+
+    SkASSERT(fNumAAHairlineConcavePaths <= fNumAAConcavePaths);
+
+    int numNonDashedPathEffects = fNumPaintWithPathEffectUses -
+                                  fNumFastPathDashEffects;
+
+    bool suitableForDash = (0 == fNumPaintWithPathEffectUses) ||
+                           (numNonDashedPathEffects < kNumPaintWithPathEffectUsesTol
+                            && 0 == sampleCount);
+
+    bool ret = suitableForDash &&
+                    (fNumAAConcavePaths - fNumAAHairlineConcavePaths)
+                    < kNumAAConcavePaths;
+    if (!ret && NULL != reason) {
+        if (!suitableForDash) {
+            if (0 != sampleCount) {
+                *reason = "Can't use multisample on dash effect.";
+            } else {
+                *reason = "Too many non dashed path effects.";
+            }
+        } else if ((fNumAAConcavePaths - fNumAAHairlineConcavePaths)
+                    >= kNumAAConcavePaths) {
+            *reason = "Too many anti-aliased concave paths.";
+        } else {
+            *reason = "Unknown reason for GPU unsuitability.";
+        }
+    }
+    return ret;
+}
+
+void SkPictureContentInfo::onDrawPoints(size_t count, const SkPaint& paint) {
+    if (paint.getPathEffect() != NULL) {
+        SkPathEffect::DashInfo info;
+        SkPathEffect::DashType dashType = paint.getPathEffect()->asADash(&info);
+        if (2 == count && SkPaint::kRound_Cap != paint.getStrokeCap() &&
+            SkPathEffect::kDash_DashType == dashType && 2 == info.fCount) {
+            ++fNumFastPathDashEffects;
+        }
+    }
+}
+
+void SkPictureContentInfo::onDrawPath(const SkPath& path, const SkPaint& paint) {
+    if (paint.isAntiAlias() && !path.isConvex()) {
+        ++fNumAAConcavePaths;
+
+        if (SkPaint::kStroke_Style == paint.getStyle() && 0 == paint.getStrokeWidth()) {
+            ++fNumAAHairlineConcavePaths;
+        }
+    }
+}
+
+void SkPictureContentInfo::onAddPaintPtr(const SkPaint* paint) {
+    if (NULL != paint && NULL != paint->getPathEffect()) {
+        ++fNumPaintWithPathEffectUses;
+    }
+}
+
+void SkPictureContentInfo::set(const SkPictureContentInfo& src) {
+    fNumOperations = src.fNumOperations;
+    fNumTexts = src.fNumTexts;
+    fNumPaintWithPathEffectUses = src.fNumPaintWithPathEffectUses;
+    fNumFastPathDashEffects = src.fNumFastPathDashEffects;
+    fNumAAConcavePaths = src.fNumAAConcavePaths;
+    fNumAAHairlineConcavePaths = src.fNumAAHairlineConcavePaths;
+}
+
+void SkPictureContentInfo::reset() {
+    fNumOperations = 0;
+    fNumTexts = 0;
+    fNumPaintWithPathEffectUses = 0;
+    fNumFastPathDashEffects = 0;
+    fNumAAConcavePaths = 0;
+    fNumAAHairlineConcavePaths = 0;
+}
+
+void SkPictureContentInfo::swap(SkPictureContentInfo* other) {
+    SkTSwap(fNumOperations, other->fNumOperations);
+    SkTSwap(fNumTexts, other->fNumTexts);
+    SkTSwap(fNumPaintWithPathEffectUses, other->fNumPaintWithPathEffectUses);
+    SkTSwap(fNumFastPathDashEffects, other->fNumFastPathDashEffects);
+    SkTSwap(fNumAAConcavePaths, other->fNumAAConcavePaths);
+    SkTSwap(fNumAAHairlineConcavePaths, other->fNumAAHairlineConcavePaths);
+}