Initial SVG backend stubbing

experimental/svg/SkSVGDevice.cpp

Index: experimental/svg/SkSVGDevice.cpp
diff --git a/experimental/svg/SkSVGDevice.cpp b/experimental/svg/SkSVGDevice.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..4a662e7b9470c71b8922fa30cd09a1e430bb7910
--- /dev/null
+++ b/experimental/svg/SkSVGDevice.cpp
@@ -0,0 +1,187 @@
+/*
+ * Copyright 2015 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include "SkSVGDevice.h"
+
+#include "SkBitmap.h"
+#include "SkDraw.h"
+#include "SkPaint.h"
+#include "SkParsePath.h"
+#include "SkStream.h"
+#include "SkXMLWriter.h"
+
+namespace {
+
+class AutoElement {
+public:
+    AutoElement(const char name[], SkXMLWriter* writer)
+        : fWriter(writer) {
+        fWriter->startElement(name);
+    }
+
+    ~AutoElement() {
+        fWriter->endElement();
+    }
+
+private:
+    SkXMLWriter* fWriter;
+};
+
+}
+
+SkBaseDevice* SkSVGDevice::Create(const SkISize& size, SkWStream* wstream) {
+    if (!SkToBool(wstream)) {
+        return NULL;
+    }
+
+    return SkNEW_ARGS(SkSVGDevice, (size, wstream));
+}
+
+SkSVGDevice::SkSVGDevice(const SkISize& size, SkWStream* wstream)
+    : fWriter(SkNEW_ARGS(SkXMLStreamWriter, (wstream))) {
+
+    fLegacyBitmap.setInfo(SkImageInfo::MakeUnknown(size.width(), size.height()));
+
+    fWriter->writeHeader();
+    fWriter->startElement("svg");
+    fWriter->addAttribute("xmlns", "http://www.w3.org/2000/svg");
+    fWriter->addAttribute("xmlns:xlink", "http://www.w3.org/1999/xlink");
+    fWriter->addS32Attribute("width", size.width());
+    fWriter->addS32Attribute("height", size.height());
+}
+
+SkSVGDevice::~SkSVGDevice() {
+    fWriter->endElement();
+    fWriter->flush();
+    SkDELETE(fWriter);
+}
+
+SkImageInfo SkSVGDevice::imageInfo() const {
+    return fLegacyBitmap.info();
+}
+
+const SkBitmap& SkSVGDevice::onAccessBitmap() {
+    return fLegacyBitmap;
+}
+
+void SkSVGDevice::addPaint(const SkPaint& paint) {
+    SkColor color = paint.getColor();
+    SkString colorStr;
+    colorStr.appendf("rgb(%u,%u,%u)", SkColorGetR(color), SkColorGetG(color), SkColorGetB(color));
+
+    SkPaint::Style style = paint.getStyle();
+    if (style == SkPaint::kFill_Style || style == SkPaint::kStrokeAndFill_Style) {
+        fWriter->addAttribute("fill", colorStr.c_str());
+    } else {
+        fWriter->addAttribute("fill", "none");
+    }
+
+    if (style == SkPaint::kStroke_Style || style == SkPaint::kStrokeAndFill_Style) {
+        fWriter->addAttribute("stroke", colorStr.c_str());
+        fWriter->addScalarAttribute("stroke-width", paint.getStrokeWidth());
+    } else {
+        fWriter->addAttribute("stroke", "none");
+    }
+}
+
+void SkSVGDevice::addTransform(const SkMatrix &t) {
+    if (t.isIdentity()) {
+        return;
+    }
+
+    SkString tstr;
+    tstr.appendf("matrix(%g %g %g %g %g %g)",
+                 SkScalarToFloat(t.getScaleX()), SkScalarToFloat(t.getSkewY()),
+                 SkScalarToFloat(t.getSkewX()), SkScalarToFloat(t.getScaleY()),
+                 SkScalarToFloat(t.getTranslateX()), SkScalarToFloat(t.getTranslateY()));
+    fWriter->addAttribute("transform", tstr.c_str());
+}
+
+void SkSVGDevice::drawPaint(const SkDraw&, const SkPaint& paint) {
+    // todo
+}
+
+void SkSVGDevice::drawPoints(const SkDraw&, SkCanvas::PointMode mode, size_t count,
+                             const SkPoint[], const SkPaint& paint) {
+    // todo
+}
+
+void SkSVGDevice::drawRect(const SkDraw& draw, const SkRect& r, const SkPaint& paint) {
+    AutoElement elem("rect", fWriter);
+
+    fWriter->addScalarAttribute("x", r.fLeft);
+    fWriter->addScalarAttribute("y", r.fTop);
+    fWriter->addScalarAttribute("width", r.width());
+    fWriter->addScalarAttribute("height", r.height());
+
+    this->addPaint(paint);
+    this->addTransform(*draw.fMatrix);
+}
+
+void SkSVGDevice::drawOval(const SkDraw&, const SkRect& oval, const SkPaint& paint) {
+    // todo
+}
+
+void SkSVGDevice::drawRRect(const SkDraw&, const SkRRect& rr, const SkPaint& paint) {
+    // todo
+}
+
+void SkSVGDevice::drawPath(const SkDraw& draw, const SkPath& path, const SkPaint& paint,
+                           const SkMatrix* prePathMatrix, bool pathIsMutable) {
+    AutoElement elem("path", fWriter);
+
+    SkString pathStr;
+    SkParsePath::ToSVGString(path, &pathStr);
+    fWriter->addAttribute("d", pathStr.c_str());
+
+    this->addPaint(paint);
+    this->addTransform(*draw.fMatrix);
+}
+
+void SkSVGDevice::drawBitmap(const SkDraw&, const SkBitmap& bitmap,
+                             const SkMatrix& matrix, const SkPaint& paint) {
+    // todo
+}
+
+void SkSVGDevice::drawSprite(const SkDraw&, const SkBitmap& bitmap,
+                             int x, int y, const SkPaint& paint) {
+    // todo
+}
+
+void SkSVGDevice::drawBitmapRect(const SkDraw&, const SkBitmap&, const SkRect* srcOrNull,
+                                 const SkRect& dst, const SkPaint& paint,
+                                 SkCanvas::DrawBitmapRectFlags flags) {
+    // todo
+}
+
+void SkSVGDevice::drawText(const SkDraw&, const void* text, size_t len,
+                           SkScalar x, SkScalar y, const SkPaint& paint) {
+    // todo
+}
+
+void SkSVGDevice::drawPosText(const SkDraw&, const void* text, size_t len,const SkScalar pos[],
+                              int scalarsPerPos, const SkPoint& offset, const SkPaint& paint) {
+    // todo
+}
+
+void SkSVGDevice::drawTextOnPath(const SkDraw&, const void* text, size_t len, const SkPath& path,
+                                 const SkMatrix* matrix, const SkPaint& paint) {
+    // todo
+}
+
+void SkSVGDevice::drawVertices(const SkDraw&, SkCanvas::VertexMode, int vertexCount,
+                               const SkPoint verts[], const SkPoint texs[],
+                               const SkColor colors[], SkXfermode* xmode,
+                               const uint16_t indices[], int indexCount,
+                               const SkPaint& paint) {
+    // todo
+}
+
+void SkSVGDevice::drawDevice(const SkDraw&, SkBaseDevice*, int x, int y,
+                             const SkPaint&) {
+    // todo
+}