src/pdf/SkPDFUtils.cpp - platform/external/skia - Gitiles


 /*
  * 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 "SkData.h"
 #include "SkGeometry.h"
 #include "SkPaint.h"
 #include "SkPath.h"
 #include "SkPDFResourceDict.h"
 #include "SkPDFUtils.h"
 #include "SkStream.h"
 #include "SkString.h"
 #include "SkPDFTypes.h"

 //static
 SkPDFArray* SkPDFUtils::RectToArray(const SkRect& rect) {
     SkPDFArray* result = new SkPDFArray();
     result->reserve(4);
     result->appendScalar(rect.fLeft);
     result->appendScalar(rect.fTop);
     result->appendScalar(rect.fRight);
     result->appendScalar(rect.fBottom);
     return result;
 }

 // static
 SkPDFArray* SkPDFUtils::MatrixToArray(const SkMatrix& matrix) {
     SkScalar values[6];
     if (!matrix.asAffine(values)) {
         SkMatrix::SetAffineIdentity(values);
     }

     SkPDFArray* result = new SkPDFArray;
     result->reserve(6);
     for (size_t i = 0; i < SK_ARRAY_COUNT(values); i++) {
         result->appendScalar(values[i]);
     }
     return result;
 }

 // static
 void SkPDFUtils::AppendTransform(const SkMatrix& matrix, SkWStream* content) {
     SkScalar values[6];
     if (!matrix.asAffine(values)) {
         SkMatrix::SetAffineIdentity(values);
     }
     for (size_t i = 0; i < SK_ARRAY_COUNT(values); i++) {
         SkPDFScalar::Append(values[i], content);
         content->writeText(" ");
     }
     content->writeText("cm\n");
 }

 // static
 void SkPDFUtils::MoveTo(SkScalar x, SkScalar y, SkWStream* content) {
     SkPDFScalar::Append(x, content);
     content->writeText(" ");
     SkPDFScalar::Append(y, content);
     content->writeText(" m\n");
 }

 // static
 void SkPDFUtils::AppendLine(SkScalar x, SkScalar y, SkWStream* content) {
     SkPDFScalar::Append(x, content);
     content->writeText(" ");
     SkPDFScalar::Append(y, content);
     content->writeText(" l\n");
 }

 // static
 void SkPDFUtils::AppendCubic(SkScalar ctl1X, SkScalar ctl1Y,
                              SkScalar ctl2X, SkScalar ctl2Y,
                              SkScalar dstX, SkScalar dstY, SkWStream* content) {
     SkString cmd("y\n");
     SkPDFScalar::Append(ctl1X, content);
     content->writeText(" ");
     SkPDFScalar::Append(ctl1Y, content);
     content->writeText(" ");
     if (ctl2X != dstX || ctl2Y != dstY) {
         cmd.set("c\n");
         SkPDFScalar::Append(ctl2X, content);
         content->writeText(" ");
         SkPDFScalar::Append(ctl2Y, content);
         content->writeText(" ");
     }
     SkPDFScalar::Append(dstX, content);
     content->writeText(" ");
     SkPDFScalar::Append(dstY, content);
     content->writeText(" ");
     content->writeText(cmd.c_str());
 }

 static void append_quad(const SkPoint quad[], SkWStream* content) {
     SkPoint cubic[4];
     SkConvertQuadToCubic(quad, cubic);
     SkPDFUtils::AppendCubic(cubic[1].fX, cubic[1].fY, cubic[2].fX, cubic[2].fY,
                             cubic[3].fX, cubic[3].fY, content);
 }

 // static
 void SkPDFUtils::AppendRectangle(const SkRect& rect, SkWStream* content) {
     // Skia has 0,0 at top left, pdf at bottom left.  Do the right thing.
     SkScalar bottom = SkMinScalar(rect.fBottom, rect.fTop);

     SkPDFScalar::Append(rect.fLeft, content);
     content->writeText(" ");
     SkPDFScalar::Append(bottom, content);
     content->writeText(" ");
     SkPDFScalar::Append(rect.width(), content);
     content->writeText(" ");
     SkPDFScalar::Append(rect.height(), content);
     content->writeText(" re\n");
 }

 // static
 void SkPDFUtils::EmitPath(const SkPath& path, SkPaint::Style paintStyle,
                           SkWStream* content) {
     // Filling a path with no area results in a drawing in PDF renderers but
     // Chrome expects to be able to draw some such entities with no visible
     // result, so we detect those cases and discard the drawing for them.
     // Specifically: moveTo(X), lineTo(Y) and moveTo(X), lineTo(X), lineTo(Y).
     enum SkipFillState {
         kEmpty_SkipFillState         = 0,
         kSingleLine_SkipFillState    = 1,
         kNonSingleLine_SkipFillState = 2,
     };
     SkipFillState fillState = kEmpty_SkipFillState;
     if (paintStyle != SkPaint::kFill_Style) {
         fillState = kNonSingleLine_SkipFillState;
     }
     SkPoint lastMovePt = SkPoint::Make(0,0);
     SkDynamicMemoryWStream currentSegment;
     SkPoint args[4];
     SkPath::Iter iter(path, false);
     for (SkPath::Verb verb = iter.next(args); verb != SkPath::kDone_Verb; verb = iter.next(args)) {
         // args gets all the points, even the implicit first point.
         switch (verb) {
             case SkPath::kMove_Verb:
                 MoveTo(args[0].fX, args[0].fY, &currentSegment);
                 lastMovePt = args[0];
                 fillState = kEmpty_SkipFillState;
                 break;
             case SkPath::kLine_Verb:
                 AppendLine(args[1].fX, args[1].fY, &currentSegment);
                 if (fillState == kEmpty_SkipFillState) {
                    if (args[0] != lastMovePt) {
                        fillState = kSingleLine_SkipFillState;
                    }
                 } else if (fillState == kSingleLine_SkipFillState) {
                     fillState = kNonSingleLine_SkipFillState;
                 }
                 break;
             case SkPath::kQuad_Verb:
                 append_quad(args, &currentSegment);
                 fillState = kNonSingleLine_SkipFillState;
                 break;
             case SkPath::kConic_Verb: {
                 const SkScalar tol = SK_Scalar1 / 4;
                 SkAutoConicToQuads converter;
                 const SkPoint* quads = converter.computeQuads(args, iter.conicWeight(), tol);
                 for (int i = 0; i < converter.countQuads(); ++i) {
                     append_quad(&quads[i * 2], &currentSegment);
                 }
             } break;
             case SkPath::kCubic_Verb:
                 AppendCubic(args[1].fX, args[1].fY, args[2].fX, args[2].fY,
                             args[3].fX, args[3].fY, &currentSegment);
                 fillState = kNonSingleLine_SkipFillState;
                 break;
             case SkPath::kClose_Verb:
                 if (fillState != kSingleLine_SkipFillState) {
                     ClosePath(&currentSegment);
                     SkData* data = currentSegment.copyToData();
                     content->write(data->data(), data->size());
                     data->unref();
                 }
                 currentSegment.reset();
                 break;
             default:
                 SkASSERT(false);
                 break;
         }
     }
     if (currentSegment.bytesWritten() > 0) {
         SkData* data = currentSegment.copyToData();
         content->write(data->data(), data->size());
         data->unref();
     }
 }

 // static
 void SkPDFUtils::ClosePath(SkWStream* content) {
     content->writeText("h\n");
 }

 // static
 void SkPDFUtils::PaintPath(SkPaint::Style style, SkPath::FillType fill,
                            SkWStream* content) {
     if (style == SkPaint::kFill_Style) {
         content->writeText("f");
     } else if (style == SkPaint::kStrokeAndFill_Style) {
         content->writeText("B");
     } else if (style == SkPaint::kStroke_Style) {
         content->writeText("S");
     }

     if (style != SkPaint::kStroke_Style) {
         NOT_IMPLEMENTED(fill == SkPath::kInverseEvenOdd_FillType, false);
         NOT_IMPLEMENTED(fill == SkPath::kInverseWinding_FillType, false);
         if (fill == SkPath::kEvenOdd_FillType) {
             content->writeText("*");
         }
     }
     content->writeText("\n");
 }

 // static
 void SkPDFUtils::StrokePath(SkWStream* content) {
     SkPDFUtils::PaintPath(
         SkPaint::kStroke_Style, SkPath::kWinding_FillType, content);
 }

 // static
 void SkPDFUtils::DrawFormXObject(int objectIndex, SkWStream* content) {
     content->writeText("/");
     content->writeText(SkPDFResourceDict::getResourceName(
             SkPDFResourceDict::kXObject_ResourceType,
             objectIndex).c_str());
     content->writeText(" Do\n");
 }

 // static
 void SkPDFUtils::ApplyGraphicState(int objectIndex, SkWStream* content) {
     content->writeText("/");
     content->writeText(SkPDFResourceDict::getResourceName(
             SkPDFResourceDict::kExtGState_ResourceType,
             objectIndex).c_str());
     content->writeText(" gs\n");
 }

 // static
 void SkPDFUtils::ApplyPattern(int objectIndex, SkWStream* content) {
     // Select Pattern color space (CS, cs) and set pattern object as current
     // color (SCN, scn)
     SkString resourceName = SkPDFResourceDict::getResourceName(
             SkPDFResourceDict::kPattern_ResourceType,
             objectIndex);
     content->writeText("/Pattern CS/Pattern cs/");
     content->writeText(resourceName.c_str());
     content->writeText(" SCN/");
     content->writeText(resourceName.c_str());
     content->writeText(" scn\n");
 }

	/*
	* 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 "SkData.h"
	#include "SkGeometry.h"
	#include "SkPaint.h"
	#include "SkPath.h"
	#include "SkPDFResourceDict.h"
	#include "SkPDFUtils.h"
	#include "SkStream.h"
	#include "SkString.h"
	#include "SkPDFTypes.h"

	//static
	SkPDFArray* SkPDFUtils::RectToArray(const SkRect& rect) {
	SkPDFArray* result = new SkPDFArray();
	result->reserve(4);
	result->appendScalar(rect.fLeft);
	result->appendScalar(rect.fTop);
	result->appendScalar(rect.fRight);
	result->appendScalar(rect.fBottom);
	return result;
	}

	// static
	SkPDFArray* SkPDFUtils::MatrixToArray(const SkMatrix& matrix) {
	SkScalar values[6];
	if (!matrix.asAffine(values)) {
	SkMatrix::SetAffineIdentity(values);
	}

	SkPDFArray* result = new SkPDFArray;
	result->reserve(6);
	for (size_t i = 0; i < SK_ARRAY_COUNT(values); i++) {
	result->appendScalar(values[i]);
	}
	return result;
	}

	// static
	void SkPDFUtils::AppendTransform(const SkMatrix& matrix, SkWStream* content) {
	SkScalar values[6];
	if (!matrix.asAffine(values)) {
	SkMatrix::SetAffineIdentity(values);
	}
	for (size_t i = 0; i < SK_ARRAY_COUNT(values); i++) {
	SkPDFScalar::Append(values[i], content);
	content->writeText(" ");
	}
	content->writeText("cm\n");
	}

	// static
	void SkPDFUtils::MoveTo(SkScalar x, SkScalar y, SkWStream* content) {
	SkPDFScalar::Append(x, content);
	content->writeText(" ");
	SkPDFScalar::Append(y, content);
	content->writeText(" m\n");
	}

	// static
	void SkPDFUtils::AppendLine(SkScalar x, SkScalar y, SkWStream* content) {
	SkPDFScalar::Append(x, content);
	content->writeText(" ");
	SkPDFScalar::Append(y, content);
	content->writeText(" l\n");
	}

	// static
	void SkPDFUtils::AppendCubic(SkScalar ctl1X, SkScalar ctl1Y,
	SkScalar ctl2X, SkScalar ctl2Y,
	SkScalar dstX, SkScalar dstY, SkWStream* content) {
	SkString cmd("y\n");
	SkPDFScalar::Append(ctl1X, content);
	content->writeText(" ");
	SkPDFScalar::Append(ctl1Y, content);
	content->writeText(" ");
	if (ctl2X != dstX \|\| ctl2Y != dstY) {
	cmd.set("c\n");
	SkPDFScalar::Append(ctl2X, content);
	content->writeText(" ");
	SkPDFScalar::Append(ctl2Y, content);
	content->writeText(" ");
	}
	SkPDFScalar::Append(dstX, content);
	content->writeText(" ");
	SkPDFScalar::Append(dstY, content);
	content->writeText(" ");
	content->writeText(cmd.c_str());
	}

	static void append_quad(const SkPoint quad[], SkWStream* content) {
	SkPoint cubic[4];
	SkConvertQuadToCubic(quad, cubic);
	SkPDFUtils::AppendCubic(cubic[1].fX, cubic[1].fY, cubic[2].fX, cubic[2].fY,
	cubic[3].fX, cubic[3].fY, content);
	}

	// static
	void SkPDFUtils::AppendRectangle(const SkRect& rect, SkWStream* content) {
	// Skia has 0,0 at top left, pdf at bottom left. Do the right thing.
	SkScalar bottom = SkMinScalar(rect.fBottom, rect.fTop);

	SkPDFScalar::Append(rect.fLeft, content);
	content->writeText(" ");
	SkPDFScalar::Append(bottom, content);
	content->writeText(" ");
	SkPDFScalar::Append(rect.width(), content);
	content->writeText(" ");
	SkPDFScalar::Append(rect.height(), content);
	content->writeText(" re\n");
	}

	// static
	void SkPDFUtils::EmitPath(const SkPath& path, SkPaint::Style paintStyle,
	SkWStream* content) {
	// Filling a path with no area results in a drawing in PDF renderers but
	// Chrome expects to be able to draw some such entities with no visible
	// result, so we detect those cases and discard the drawing for them.
	// Specifically: moveTo(X), lineTo(Y) and moveTo(X), lineTo(X), lineTo(Y).
	enum SkipFillState {
	kEmpty_SkipFillState = 0,
	kSingleLine_SkipFillState = 1,
	kNonSingleLine_SkipFillState = 2,
	};
	SkipFillState fillState = kEmpty_SkipFillState;
	if (paintStyle != SkPaint::kFill_Style) {
	fillState = kNonSingleLine_SkipFillState;
	}
	SkPoint lastMovePt = SkPoint::Make(0,0);
	SkDynamicMemoryWStream currentSegment;
	SkPoint args[4];
	SkPath::Iter iter(path, false);
	for (SkPath::Verb verb = iter.next(args); verb != SkPath::kDone_Verb; verb = iter.next(args)) {
	// args gets all the points, even the implicit first point.
	switch (verb) {
	case SkPath::kMove_Verb:
	MoveTo(args[0].fX, args[0].fY, &currentSegment);
	lastMovePt = args[0];
	fillState = kEmpty_SkipFillState;
	break;
	case SkPath::kLine_Verb:
	AppendLine(args[1].fX, args[1].fY, &currentSegment);
	if (fillState == kEmpty_SkipFillState) {
	if (args[0] != lastMovePt) {
	fillState = kSingleLine_SkipFillState;
	}
	} else if (fillState == kSingleLine_SkipFillState) {
	fillState = kNonSingleLine_SkipFillState;
	}
	break;
	case SkPath::kQuad_Verb:
	append_quad(args, &currentSegment);
	fillState = kNonSingleLine_SkipFillState;
	break;
	case SkPath::kConic_Verb: {
	const SkScalar tol = SK_Scalar1 / 4;
	SkAutoConicToQuads converter;
	const SkPoint* quads = converter.computeQuads(args, iter.conicWeight(), tol);
	for (int i = 0; i < converter.countQuads(); ++i) {
	append_quad(&quads[i * 2], &currentSegment);
	}
	} break;
	case SkPath::kCubic_Verb:
	AppendCubic(args[1].fX, args[1].fY, args[2].fX, args[2].fY,
	args[3].fX, args[3].fY, &currentSegment);
	fillState = kNonSingleLine_SkipFillState;
	break;
	case SkPath::kClose_Verb:
	if (fillState != kSingleLine_SkipFillState) {
	ClosePath(&currentSegment);
	SkData* data = currentSegment.copyToData();
	content->write(data->data(), data->size());
	data->unref();
	}
	currentSegment.reset();
	break;
	default:
	SkASSERT(false);
	break;
	}
	}
	if (currentSegment.bytesWritten() > 0) {
	SkData* data = currentSegment.copyToData();
	content->write(data->data(), data->size());
	data->unref();
	}
	}

	// static
	void SkPDFUtils::ClosePath(SkWStream* content) {
	content->writeText("h\n");
	}

	// static
	void SkPDFUtils::PaintPath(SkPaint::Style style, SkPath::FillType fill,
	SkWStream* content) {
	if (style == SkPaint::kFill_Style) {
	content->writeText("f");
	} else if (style == SkPaint::kStrokeAndFill_Style) {
	content->writeText("B");
	} else if (style == SkPaint::kStroke_Style) {
	content->writeText("S");
	}

	if (style != SkPaint::kStroke_Style) {
	NOT_IMPLEMENTED(fill == SkPath::kInverseEvenOdd_FillType, false);
	NOT_IMPLEMENTED(fill == SkPath::kInverseWinding_FillType, false);
	if (fill == SkPath::kEvenOdd_FillType) {
	content->writeText("*");
	}
	}
	content->writeText("\n");
	}

	// static
	void SkPDFUtils::StrokePath(SkWStream* content) {
	SkPDFUtils::PaintPath(
	SkPaint::kStroke_Style, SkPath::kWinding_FillType, content);
	}

	// static
	void SkPDFUtils::DrawFormXObject(int objectIndex, SkWStream* content) {
	content->writeText("/");
	content->writeText(SkPDFResourceDict::getResourceName(
	SkPDFResourceDict::kXObject_ResourceType,
	objectIndex).c_str());
	content->writeText(" Do\n");
	}

	// static
	void SkPDFUtils::ApplyGraphicState(int objectIndex, SkWStream* content) {
	content->writeText("/");
	content->writeText(SkPDFResourceDict::getResourceName(
	SkPDFResourceDict::kExtGState_ResourceType,
	objectIndex).c_str());
	content->writeText(" gs\n");
	}

	// static
	void SkPDFUtils::ApplyPattern(int objectIndex, SkWStream* content) {
	// Select Pattern color space (CS, cs) and set pattern object as current
	// color (SCN, scn)
	SkString resourceName = SkPDFResourceDict::getResourceName(
	SkPDFResourceDict::kPattern_ResourceType,
	objectIndex);
	content->writeText("/Pattern CS/Pattern cs/");
	content->writeText(resourceName.c_str());
	content->writeText(" SCN/");
	content->writeText(resourceName.c_str());
	content->writeText(" scn\n");
	}