SkDocument base for pdf, xps, etc.

gm/aaclip.cpp

 /*
  * Copyright 2011 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "gm.h"
 #include "SkCanvas.h"
 #include "SkPath.h"
 
+class SkWStream;
+class SkDocument : public SkRefCnt {
+public:
+    static SkDocument* CreatePDF(SkWStream*);
+
+    SkCanvas* beginPage(SkScalar width, SkScalar height,
+                        const SkRect* content = NULL);
+    void endPage();
+    void close();
+
+protected:
+    SkDocument(SkWStream*);
+    virtual ~SkDocument();
+
+    virtual SkCanvas* onBeginPage(SkScalar width, SkScalar height,
+                                  const SkRect& content) = 0;
+    virtual void onEndPage() = 0;
+    virtual void onClose(SkWStream*) = 0;
+
+    enum State {
+        kBeforePage_State,
+        kInPage_State,
+        kAfterPage_State,
+        kClosed_State
+    };
+    State getState() const { return fState; }
+
+private:
+    SkWStream* fStream;
+
+    enum State {
+        kBeforePage_State,
+        kInPage_State,
+        kAfterPage_State,
+        kClosed_State
+    };
+    State fState;    
+};
+
+#include "SkPDFDocument.h"
+#include "SkPDFDevice.h"
+
+class SkDocument_PDF : public SkDocument {
+public:
+    SkDocument_PDF(SkWStream* stream) : SkDocument(stream) {
+        fDoc = new SkPDFDocument;
+        fCanvas = NULL;
+        fDevice = NULL;
+    }
+    
+    virtual ~SkDocument_PDF() {
+        this->close();
+        delete fDoc;
+    }
+
+protected:
+    virtual SkCanvas* onBeginPage(SkScalar width, SkScalar height,
+                                  const SkRect& content) SK_OVERRIDE {
+        this->endPage();
+
+        SkISize pageS, contentS;
+        SkMatrix matrix;
+
+        pageS.set(SkScalarRoundToInt(width), SkScalarRoundToInt(height));
+        contentS.set(SkScalarRoundToInt(content.width()),
+                     SkScalarRoundToInt(content.height()));
+        matrix.setTranslate(content.fLeft, content.fTop);
+
+        fDevice = new SkPDFDevice(pageS, contentS, matrix);
+        fCanvas = new SkCanvas(fDevice);
+        return fCanvas;
+    }
+
+    virtual void onEndPage() SK_OVERRIDE {
+        if (fCanvas) {
+            fCanvas->flush();
+            fDoc->appendPage(fDevice);
+
+            fCanvas->unref();
+            fDevice->unref();
+
+            fCanvas = NULL;
+            fDevice = NULL;
+        }
+    }
+
+    virtual void onClose(SkWStream* stream) SK_OVERRIDE {
+        fDoc->emitPDF(stream);
+
+        delete fDoc;
+        SkSafeUnref(fCanvas);
+        SkSafeUnref(fDevice);
+
+        fDoc = NULL;
+        fCanvas = NULL;
+        fDevice = NULL;
+    }
+
+private:
+    SkPDFDocument*  fDoc;
+    SkPDFDevice*    fDevice;
+    SkCanvas*       fCanvas;
+};
+
+///////////////////////////////////////////////////////////////////////////////
+
+SkDocument* SkDocument::CreatePDF(SkScalar width, SkScalar height,
+                                  const SkRect* content) {
+    if (width > 0 && height > 0) {
+        SkRect outer = SkRect::MakeWH(width, height);
+        SkRect inner;
+        if (content) {
+            inner = *content;
+            if (!inner.intersect(outer)) {
+                return NULL;
+            }
+        } else {
+            inner = outer;
+        }
+        return new SkDocument_PDF(width, height, inner);
+    }
+    return NULL;
+}
+
+SkDocument::SkDocument() : fState(kBeforePage_State) {
+}
+
+SkDocument::~SkDocument() {
+}
+
+SkCanvas* SkDocument::beginPage(SkScalar width, SkScalar height,
+                                const SkRect* content) {
+    if (width <= 0 || height <= 0) {
+        return NULL;
+    }
+
+    SkRect outer = SkRect::MakeWH(width, height);
+    SkRect inner;
+    if (content) {
+        inner = *content;
+        if (!inner.intersect(outer)) {
+            return NULL;
+        }
+    } else {
+        inner = outer;
+    }
+
+    for (;;) {
+        switch (fState) {
+            case kBeforePage_State:
+            case kAfterPage_State:
+                fState = kInPage_State;
+                return this->beginPage(width, height, inner);
+            case kInPage_State:
+                this->endPage();
+                break;
+            case kClosed_State:
+                return NULL;
+        }
+    }
+    SkASSERT(!"never get here");
+    return NULL;
+}
+
+void SkDocument::endPage() {
+    if (kInPage_State == fState) {
+        this->onEndPage();
+    }
+}
+
+void SkDocument::close() {
+    for (;;) {
+        switch (fState) {
+            case kBeforePage_State:
+            case kAfterPage_State:
+                fState = kClosed_State;
+                this->onClose(fStream);
+                return;
+            case kInPage_State:
+                this->endPage();
+                break;
+            case kClosed_State:
+                return;
+        }
+    }
+}
+
+static void draw(SkCanvas* canvas) {
+    SkPaint paint;
+    paint.setAntiAlias(true);
+    paint.setTextSize(50);
+    canvas->drawText("Hello PDF", 9, 100, 100, paint);
+    
+    paint.setStyle(SkPaint::kStroke_Style);
+    paint.setStrokeWidth(2);
+    SkRect r = { 0, 0, 8.5f * 72, 11.0f * 72 };
+    r.inset(72 * 3 / 4, 72 * 3 / 4);
+    canvas->drawRect(r, paint);
+}
+
+static void test_pdf(SkCanvas* canvas) {
+    SkDocument* doc = SkDocument::CreatePDF(72 * 8.5f, 72 * 11.0f);
+    draw(doc->beginPage());
+    doc->endPage();
+    
+    SkFILEWStream stream("/skia/trunk/test.pdf");
+    doc->close(&stream);
+    doc->unref();
+}
+
+///////////////////////////////////////////////////////////////////////////////
+
 #include "SkGradientShader.h"
 static void test_shallow_gradient(SkCanvas* canvas, SkScalar width, SkScalar height) {
     SkColor colors[] = { 0xFF7F7F7F, 0xFF7F7F7F, 0xFF000000 };
     SkScalar pos[] = { 0, 0.35f, SK_Scalar1 };
     SkPoint pts[] = { { 0, 0 }, { width, height } };
     SkShader* s = SkGradientShader::CreateLinear(pts, colors, pos,
                                                  SK_ARRAY_COUNT(colors),
                                                  SkShader::kClamp_TileMode);
     SkPaint paint;
     paint.setShader(s)->unref();
@@ skipping 190 matching lines @@
 protected:
     virtual SkString onShortName() SK_OVERRIDE {
         return SkString("aaclip");
     }
 
     virtual SkISize onISize() SK_OVERRIDE {
         return SkISize::Make(640, 480);
     }
 
     virtual void onDraw(SkCanvas* canvas) SK_OVERRIDE {
+        if (true) {
+            test_pdf(canvas); return;
+        }
         if (false) {
             SkRect bounds;
             canvas->getClipBounds(&bounds);
             test_shallow_gradient(canvas, bounds.width(), bounds.height()); return;
         }
         if (false) {
             test_giant_dash(canvas); return;
         }
         if (false) {
             test_grad(canvas); return;
@@ skipping 23 matching lines @@
         draw_rect_tests(canvas);
     }
 
     virtual uint32_t onGetFlags() const { return kSkipPipe_Flag; }
 
 private:
     typedef skiagm::GM INHERITED;
 };
 
 DEF_GM( return SkNEW(AAClipGM); )