Basic support for Type3 Fonts in Pdf + various refactorings

experimental/PdfViewer/SkPdfBasics.h

Index: experimental/PdfViewer/SkPdfBasics.h
===================================================================
--- experimental/PdfViewer/SkPdfBasics.h	(revision 0)
+++ experimental/PdfViewer/SkPdfBasics.h	(revision 0)
@@ -0,0 +1,136 @@
+#ifndef __DEFINED__SkPdfBasics
+#define __DEFINED__SkPdfBasics
+
+#include "podofo.h"
+using namespace PoDoFo;
+
+#include <iostream>
+#include <cstdio>
+#include <stack>
+
+//#define PDF_TRACE
+//#define PDF_TRACE_DIFF_IN_PNG
+//#define PDF_DEBUG_NO_CLIPING
+//#define PDF_DEBUG_NO_PAGE_CLIPING
+//#define PDF_DEBUG_3X
+
+class SkPdfFont;
+class SkPdfDoc;
+
+// TODO(edisonn): better class design.
+struct PdfColorOperator {
+    std::string fColorSpace;  // TODO(edisonn): use SkString
+    SkColor fColor;
+    double fOpacity;  // ca or CA
+    // TODO(edisonn): add here other color space options.
+
+    void setRGBColor(SkColor color) {
+        // TODO(edisonn): ASSERT DeviceRGB is the color space.
+        fColor = color;
+    }
+    // TODO(edisonn): double check the default values for all fields.
+    PdfColorOperator() : fColor(SK_ColorBLACK), fOpacity(1) {}
+
+    void applyGraphicsState(SkPaint* paint) {
+        paint->setColor(SkColorSetA(fColor, fOpacity * 255));
+    }
+};
+
+// TODO(edisonn): better class design.
+struct PdfGraphicsState {
+    SkMatrix            fMatrix;
+    SkMatrix            fMatrixTm;
+    SkMatrix            fMatrixTlm;
+
+    double              fCurPosX;
+    double              fCurPosY;
+
+    double              fCurFontSize;
+    bool                fTextBlock;
+    SkPdfFont*          fSkFont;
+    SkPath              fPath;
+    bool                fPathClosed;
+
+    // Clip that is applied after the drawing is done!!!
+    bool                fHasClipPathToApply;
+    SkPath              fClipPath;
+
+    PdfColorOperator    fStroking;
+    PdfColorOperator    fNonStroking;
+
+    double              fLineWidth;
+    double              fTextLeading;
+    double              fWordSpace;
+    double              fCharSpace;
+
+    SkPdfResourceDictionary* fResources;
+
+    SkBitmap            fSMask;
+
+    PdfGraphicsState() {
+        fCurPosX      = 0.0;
+        fCurPosY      = 0.0;
+        fCurFontSize  = 0.0;
+        fTextBlock    = false;
+        fMatrix       = SkMatrix::I();
+        fMatrixTm     = SkMatrix::I();
+        fMatrixTlm    = SkMatrix::I();
+        fPathClosed   = true;
+        fLineWidth    = 0;
+        fTextLeading  = 0;
+        fWordSpace    = 0;
+        fCharSpace    = 0;
+        fHasClipPathToApply = false;
+        fResources    = NULL;
+        fSkFont       = NULL;
+    }
+
+    void applyGraphicsState(SkPaint* paint, bool stroking) {
+        if (stroking) {
+            fStroking.applyGraphicsState(paint);
+        } else {
+            fNonStroking.applyGraphicsState(paint);
+        }
+
+        // TODO(edisonn): get this from pdfContext->options,
+        // or pdfContext->addPaintOptions(&paint);
+        paint->setAntiAlias(true);
+
+        // TODO(edisonn): dashing, miter, ...
+        paint->setStrokeWidth(SkDoubleToScalar(fLineWidth));
+    }
+};
+
+// TODO(edisonn): better class design.
+struct PdfInlineImage {
+    std::map<std::string, std::string> fKeyValuePairs;
+    std::string fImageData;
+};
+
+// TODO(edisonn): better class design.
+struct PdfContext {
+    std::stack<SkPdfObject*>        fObjectStack;
+    std::stack<PdfGraphicsState>    fStateStack;
+    PdfGraphicsState                fGraphicsState;
+    SkPdfDoc*                       fPdfDoc;
+    SkMatrix                        fOriginalMatrix;
+
+    PdfInlineImage                  fInlineImage;
+
+    PdfContext(SkPdfDoc* doc) :  fPdfDoc(doc) {}
+
+};
+
+//  TODO(edisonn): temporary code, to report how much of the PDF we actually think we rendered.
+enum PdfResult {
+    kOK_PdfResult,
+    kPartial_PdfResult,
+    kNYI_PdfResult,
+    kIgnoreError_PdfResult,
+    kError_PdfResult,
+    kUnsupported_PdfResult,
+
+    kCount_PdfResult
+};
+
+#endif  // __DEFINED__SkPdfBasics