Resurrect pathfinder in viewer and rename to "bisect"

Bug: skia:
Change-Id: If8d2f46b8f27fefc3a0f983eb649654e0fb4afcb
Reviewed-on: https://skia-review.googlesource.com/108685
Commit-Queue: Chris Dalton <csmartdalton@google.com>
Reviewed-by: Brian Osman <brianosman@google.com>

1 files changed, 54 insertions, 0 deletions

diff --git a/tools/viewer/BisectSlide.h b/tools/viewer/BisectSlide.h
new file mode 100644
index 0000000000..c5300c6396
--- /dev/null
+++ b/tools/viewer/BisectSlide.h
@@ -0,0 +1,54 @@
+/*
+ * Copyright 2018 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#ifndef BisectSlide_DEFINED
+#define BisectSlide_DEFINED
+
+#include "SkCanvas.h"
+#include "SkPath.h"
+#include "Slide.h"
+#include <stack>
+
+/**
+ * This is a simple utility designed to extract the paths from an SKP file and then isolate a single
+ * one of them via bisect. Use the 'x' and 'X' keys to guide a binary search:
+ *
+ *   'x': Throw out half the paths.
+ *   'X': Toggle which half gets tossed and which half is kept.
+ *   'Z': Back up one level.
+ *   'D': Dump the path.
+ */
+class BisectSlide : public Slide, public SkCanvas {
+public:
+    static sk_sp<BisectSlide> Create(const char filepath[]);
+
+    // Slide overrides.
+    SkISize getDimensions() const override { return fDrawBounds.size(); }
+    bool onChar(SkUnichar c) override;
+    void draw(SkCanvas* canvas) override;
+
+private:
+    BisectSlide(const char filepath[]);
+
+    // SkCanvas override called only during creation.
+    void onDrawPath(const SkPath& path, const SkPaint& paint) override;
+
+    struct FoundPath {
+        SkPath fPath;
+        SkPaint fPaint;
+        SkMatrix fViewMatrix;
+    };
+
+    SkString fFilePath;
+    SkIRect fDrawBounds = SkIRect::MakeEmpty();
+    SkTArray<FoundPath> fFoundPaths;
+    SkTArray<FoundPath> fTossedPaths;
+    SkTArray<char> fTrail;
+    std::stack<std::pair<SkTArray<FoundPath>, SkTArray<FoundPath>>> fPathHistory;
+};
+
+#endif