1 files changed, 76 insertions, 0 deletions
diff --git a/modules/skshaper/src/SkShaper_primitive.cpp b/modules/skshaper/src/SkShaper_primitive.cpp
new file mode 100644
index 0000000000..06a8bec41c
--- /dev/null
+++ b/modules/skshaper/src/SkShaper_primitive.cpp
@@ -0,0 +1,76 @@
+/*
+ * Copyright 2016 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+#include "SkShaper.h"
+#include "SkStream.h"
+#include "SkTextBlob.h"
+#include "SkTypeface.h"
+
+struct SkShaper::Impl {
+    sk_sp<SkTypeface> fTypeface;
+};
+
+SkShaper::SkShaper(sk_sp<SkTypeface> tf) : fImpl(new Impl) {
+    fImpl->fTypeface = tf ? std::move(tf) : SkTypeface::MakeDefault();
+}
+
+SkShaper::~SkShaper() {}
+
+bool SkShaper::good() const { return true; }
+
+// This example only uses public API, so we don't use SkUTF8_NextUnichar.
+unsigned utf8_lead_byte_to_count(const char* ptr) {
+    uint8_t c = *(const uint8_t*)ptr;
+    SkASSERT(c <= 0xF7);
+    SkASSERT((c & 0xC0) != 0x80);
+    return (((0xE5 << 24) >> ((unsigned)c >> 4 << 1)) & 3) + 1;
+}
+
+SkPoint SkShaper::shape(SkTextBlobBuilder* builder,
+                        const SkPaint& srcPaint,
+                        const char* utf8text,
+                        size_t textBytes,
+                        bool leftToRight,
+                        SkPoint point,
+                        SkScalar width) const {
+    sk_ignore_unused_variable(leftToRight);
+
+    SkPaint paint(srcPaint);
+    paint.setTypeface(fImpl->fTypeface);
+    paint.setTextEncoding(SkPaint::kUTF8_TextEncoding);
+    int glyphCount = paint.countText(utf8text, textBytes);
+    if (glyphCount <= 0) {
+        return point;
+    }
+    SkRect bounds;
+    SkPaint::FontMetrics metrics;
+    paint.getFontMetrics(&metrics);
+    point.fY -= metrics.fAscent;
+    (void)paint.measureText(utf8text, textBytes, &bounds);
+    paint.setTextEncoding(SkPaint::kGlyphID_TextEncoding);
+    const SkTextBlobBuilder::RunBuffer& runBuffer =
+        builder->allocRunTextPosH(paint, glyphCount, point.y(), textBytes, SkString(), &bounds);
+    memcpy(runBuffer.utf8text, utf8text, textBytes);
+    const char* txtPtr = utf8text;
+    for (int i = 0; i < glyphCount; ++i) {
+        // Each charater maps to exactly one glyph via SkGlyphCache::unicharToGlyph().
+        runBuffer.clusters[i] = SkToU32(txtPtr - utf8text);
+        txtPtr += utf8_lead_byte_to_count(txtPtr);
+        SkASSERT(txtPtr <= utf8text + textBytes);
+    }
+    paint.setTextEncoding(SkPaint::kUTF8_TextEncoding);
+    (void)paint.textToGlyphs(utf8text, textBytes, runBuffer.glyphs);
+    (void)paint.getTextWidths(utf8text, textBytes, runBuffer.pos);
+    SkScalar x = point.x();
+    for (int i = 0; i < glyphCount; ++i) {
+        SkScalar w = runBuffer.pos[i];
+        runBuffer.pos[i] = x;
+        x += w;
+    }
+    point.fY += metrics.fDescent + metrics.fLeading;
+
+    return point;
+}