XPS, DM: add SkDocument::CreateXPS

src/doc/SkDocument_XPS.cpp

+/*
+ * 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 "SkDocument.h"
+#include "SkXPSDevice.h"
+#include "SkStream.h"
+
+class SkDocument_XPS : public SkDocument {
+public:
+    SkDocument_XPS(SkWStream* stream,
+                   void (*doneProc)(SkWStream*, bool),
+                   SkScalar dpi)
+        : SkDocument(stream, doneProc) {
+        const SkScalar kPointsPerMeter = SkDoubleToScalar(360000.0 / 127.0);
+        fUnitsPerMeter.set(kPointsPerMeter, kPointsPerMeter);
+        SkScalar pixelsPerMeterScale = SkDoubleToScalar(dpi * 5000.0 / 127.0);
+        fPixelsPerMeter.set(pixelsPerMeterScale, pixelsPerMeterScale);
+        fDevice.beginPortfolio(stream);
+    }
+
+    virtual ~SkDocument_XPS() {
+        // subclasses must call close() in their destructors
+        this->close();
+    }
+
+protected:
+    virtual SkCanvas* onBeginPage(SkScalar width,
+                                  SkScalar height,
+                                  const SkRect& trimBox) SK_OVERRIDE {
+        fDevice.beginSheet(fUnitsPerMeter, fPixelsPerMeter,
+                           SkSize::Make(width, height));
+        fCanvas.reset(SkNEW_ARGS(SkCanvas, (&fDevice)));
+        fCanvas->clipRect(trimBox);
+        fCanvas->translate(trimBox.x(), trimBox.y());
+        return fCanvas.get();
+    }
+
+    void onEndPage() SK_OVERRIDE {
+        SkASSERT(fCanvas.get());
+        fCanvas->flush();
+        fCanvas.reset(NULL);
+        fDevice.endSheet();
+    }
+
+    bool onClose(SkWStream*) SK_OVERRIDE {
+        SkASSERT(!fCanvas.get());
+        return fDevice.endPortfolio();
+    }
+
+    void onAbort() SK_OVERRIDE {}
+
+private:
+    SkXPSDevice fDevice;
+    SkAutoTUnref<SkCanvas> fCanvas;
+    SkVector fUnitsPerMeter;
+    SkVector fPixelsPerMeter;
+};
+
+///////////////////////////////////////////////////////////////////////////////
+
+SkDocument* SkDocument::CreateXPS(SkWStream* stream, SkScalar dpi) {
+    return stream ? SkNEW_ARGS(SkDocument_XPS, (stream, NULL, dpi)) : NULL;
+}
+
+static void delete_wstream(SkWStream* stream, bool aborted) {
+    SkDELETE(stream);
+}
+
+SkDocument* SkDocument::CreateXPS(const char path[], SkScalar dpi) {
+    SkAutoTDelete<SkFILEWStream> stream(SkNEW_ARGS(SkFILEWStream, (path)));
+    if (!stream->isValid()) {
+        return NULL;
+    }
+    return SkNEW_ARGS(SkDocument_XPS, (stream.detach(), delete_wstream, dpi));
+}