Reland "Have draw(Text|PosText|PosTextH) use a single entry on the device"

This reverts commit 74b390d6b136a60f1df15ac5ecd19bd8ad5a394b.

Reason for revert: reverting to add patch for valgrind

Original change's description:
> Revert "Have draw(Text|PosText|PosTextH) use a single entry on the device"
> 
> This reverts commit 4225b3220ef4bf50f0d9403f812ea94d50c4ee59.
> 
> Reason for revert: made valgrind unhappy.
> 
> Original change's description:
> > Have draw(Text|PosText|PosTextH) use a single entry on the device
> > 
> > Handle the positioning of drawText at the canvas layer. Simplify
> > the code by removing similar implementations.
> > 
> > Change-Id: I8b711783435072f560e29fca1dd934fa2e345ed2
> > Reviewed-on: https://skia-review.googlesource.com/127131
> > Reviewed-by: Ben Wagner <bungeman@google.com>
> > Commit-Queue: Herb Derby <herb@google.com>
> 
> TBR=jvanverth@google.com,bungeman@google.com,herb@google.com
> 
> Change-Id: I65c9d30ae6ecb1f87e8660e56d8f8ce5daab7551
> No-Presubmit: true
> No-Tree-Checks: true
> No-Try: true
> Reviewed-on: https://skia-review.googlesource.com/132403
> Reviewed-by: Hal Canary <halcanary@google.com>
> Commit-Queue: Hal Canary <halcanary@google.com>

TBR=jvanverth@google.com,halcanary@google.com,bungeman@google.com,herb@google.com

Change-Id: I9bbb73aac447b51eb8215ac42331759fa4c9fa45
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://skia-review.googlesource.com/132580
Reviewed-by: Herb Derby <herb@google.com>
Commit-Queue: Herb Derby <herb@google.com>

1 files changed, 72 insertions, 0 deletions

diff --git a/src/core/SkGlyphRun.h b/src/core/SkGlyphRun.h
new file mode 100644
index 0000000000..17b4297208
--- /dev/null
+++ b/src/core/SkGlyphRun.h
@@ -0,0 +1,72 @@
+/*
+ * Copyright 2018 The Android Open Source Project
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#ifndef SkGlyphRunInfo_DEFINED
+#define SkGlyphRunInfo_DEFINED
+
+#include <memory>
+#include <vector>
+
+#include "SkDescriptor.h"
+#include "SkMask.h"
+#include "SkPath.h"
+#include "SkPoint.h"
+#include "SkTypes.h"
+
+class SkGlyphRun {
+public:
+    SkGlyphRun() = default;
+    SkGlyphRun(SkGlyphRun&&) = default;
+    static SkGlyphRun MakeFromDrawText(
+            const SkPaint& paint, const void* bytes, size_t byteLength,
+            SkPoint origin);
+    static SkGlyphRun MakeFromDrawPosTextH(
+            const SkPaint& paint, const void* bytes, size_t byteLength,
+            const SkScalar xpos[], SkScalar constY);
+    static SkGlyphRun MakeFromDrawPosText(
+            const SkPaint& paint, const void* bytes, size_t byteLength,
+            const SkPoint pos[]);
+
+    size_t runSize() const { return fRunSize; }
+    uint16_t uniqueSize() const { return fUniqueSize; }
+
+    // copyGlyphIDs is temporary glue to work with the existing system. Don't use with new code.
+    std::unique_ptr<SkGlyphID[]> copyGlyphIDs() const;
+    const SkScalar* getPositions() const {
+        return reinterpret_cast<const SkScalar*>(fPositions.get());
+    }
+
+private:
+    SkGlyphRun(size_t runSize,
+               std::unique_ptr<uint16_t[]>&& denseIndex,
+               std::unique_ptr<SkPoint[]>&& positions,
+               uint16_t uniqueSize,
+               std::unique_ptr<SkGlyphID[]>&& uniqueGlyphIDs);
+
+    std::unique_ptr<uint16_t[]>  fDenseIndex;
+    std::unique_ptr<SkPoint[]>   fPositions;
+    std::unique_ptr<SkGlyphID[]> fUniqueGlyphs;
+    const size_t                 fRunSize{0};
+    const uint16_t               fUniqueSize{0};
+};
+
+template <typename T>
+class SkSpan {
+public:
+    SkSpan(const T* ptr, size_t size) : fPtr{ptr}, fSize{size} {}
+    SkSpan(const std::vector<T>& v) : fPtr{v.data()}, fSize{v.size()} {}
+    const T& operator [] (ptrdiff_t i) const { return fPtr[i]; }
+    const T* begin() const { return fPtr; }
+    const T* end() const { return fPtr + fSize; }
+    ptrdiff_t size() const { return fSize; }
+
+private:
+    const T* fPtr;
+    size_t fSize;
+};
+
+#endif  // SkGlyphRunInfo_DEFINED