1 // Copyright (c) 2007-2009 Nokia Corporation and/or its subsidiary(-ies).

     2 // All rights reserved.

     3 // This component and the accompanying materials are made available

     4 // under the terms of "Eclipse Public License v1.0"

     5 // which accompanies this distribution, and is available

     6 // at the URL "http://www.eclipse.org/legal/epl-v10.html".

     7 //

     8 // Initial Contributors:

     9 // Nokia Corporation - initial contribution.

    10 //

    11 // Contributors:

    12 //

    13 // Description:

    14 //

    15 

    16 #ifndef SWDIRECTGDIPOLYGON_H

    17 #define SWDIRECTGDIPOLYGON_H

    18 

    19 /**

    20 @file

    21 @internalComponent

    22 */

    23 

    24 #include "directgdiadapter.h"

    25 #include <gdi.h>

    26 #include <e32base.h>

    27 

    28 /**

    29 A utility class to efficiently fill polygons.

    30 @see CSwDirectGdiEngine::PolyFill

    31 @see CSwDirectGdiEngine::PolyFillLarge

    32 */

    33 NONSHARABLE_CLASS(CSwDirectGdiPolygonFiller) : public CBase

    34 	{

    35 public:

    36 

    37 	/**

    38 	Describes how pixels are to be displayed in the polygon. aUsage should be set to

    39 	one of these values before CSwDirectGdiPolygonFiller::Construct is used.

    40 	*/

    41 	enum TUsage

    42 		{

    43 		/**

    44 		A request for all pixel runs in sequential order.

    45 		*/

    46 		EGetAllPixelRunsSequentially,

    47 		/**

    48 		A request for all pixel runs in sequential order but only for specified lines.

    49 		*/

    50 		EGetPixelRunsSequentiallyForSpecifiedScanLines

    51 		};

    52 public:

    53 	CSwDirectGdiPolygonFiller();

    54 	~CSwDirectGdiPolygonFiller();

    55 	void Construct(const TArray<TPoint>* aPointArray, DirectGdi::TFillRule aFillRule,TUsage aUsage=EGetAllPixelRunsSequentially); // N.B. this cannot fail

    56 	void Construct(const TPoint* aPointList,TInt aNumPoints, DirectGdi::TFillRule aFillRule, TUsage aUsage=EGetAllPixelRunsSequentially); // N.B. this cannot fail

    57 	void Reset();

    58 	void GetNextPixelRun(TBool& aExists, TInt& aScanLine, TInt& aStart, TInt& aEnd);

    59 	void GetNextPixelRunOnSpecifiedScanLine(TBool& aExists, TInt aScanLine, TInt& aStart, TInt& aEnd);

    60 private: // data-types for the fast algorithm

    61 	struct SFastEdge

    62 		{

    63 		TInt upperVertex;

    64 		TInt lowerVertex;

    65 		TInt firstVertex;

    66 		};

    67 	struct SFastScanLineIntersection;

    68 	struct SFastActiveEdge

    69 		{

    70 		SFastEdge* edgePtr;

    71 		TLinearDDA lineGenerator;

    72 		SFastScanLineIntersection* scanLineIntersectionPtr;

    73 		};

    74 	struct SFastScanLineIntersection

    75 		{

    76 		TInt firstPixel;

    77 		TInt lastPixel;

    78 		SFastActiveEdge* activeEdgePtr;

    79 		};

    80 private: // data-types for the slow algorithm

    81 	struct SSlowScanLineIntersection

    82 		{

    83 		TInt firstPixel;

    84 		TInt lastPixel;

    85 		TInt firstVertexOfEdge;

    86 		};

    87 private: // data-types for both algorithms

    88 	struct SFastData

    89 		{

    90 		TPoint* vertexList;

    91 		SFastEdge* edgeList;

    92 		SFastActiveEdge* activeEdgeList;

    93 		SFastScanLineIntersection* scanLineIntersectionList;

    94 		TInt numActiveEdges;

    95 		TInt numScanLineIntersections;

    96 		TInt nextEdgeToActivate;

    97 		};

    98 	struct SSlowData

    99 		{

   100 		enum {EStoreSize=8};

   101 		TLinearDDA lineGenerator;

   102 		SSlowScanLineIntersection scanLineIntersectionList[EStoreSize];

   103 		TInt numIntersectionsWithSameFirstPixelPreviouslyMet;

   104 		TInt numIntersectionsWithSameFirstPixelMetThisTime;

   105 		TInt numScanLineIntersections;

   106 		TBool scanLineComplete;

   107 		TInt firstPixelOfLastIntersectionInPrevBuffer;

   108 		};

   109 private:

   110 	void Construct(DirectGdi::TFillRule aFillRule, TUsage aUsage);

   111 	void FastHandleVertexIntersection(TInt& aCurrentActiveEdge, TBool aIsLowerVertex);

   112 	void SetFastIntersection(SFastActiveEdge& aActiveEdge, SFastScanLineIntersection& aScanLineIntersection);

   113 	void SlowHandleVertexIntersection(SSlowScanLineIntersection& aScanLineIntersection, TInt& aVertexStartingCurrentEdge,TBool aIsLowerVertex);

   114 	void JumpToCurrentScanLine(TLinearDDA& aLineGenerator, const TPoint& aUpper, const TPoint& aLower,TPoint& aStartPos, TPoint& aEndPos) const;

   115 	const TPoint& Point(TInt aIndex);

   116 private:

   117 	const TArray<TPoint>* iPointArray; // not owned by the class

   118 	DirectGdi::TFillRule iFillRule;

   119 	TBool iUseFastAlgorithm;

   120 	TInt iNumVertexes;

   121 	TBool iToggler; // used by EAlternate fill-rule

   122 	TInt iNestingLevel; // used by EWinding fill-rule

   123 	TInt iScanLineIntersection;

   124 	TInt iRightMostPixelOnScanLine;

   125 	TInt iFirstVertex;

   126 	TBool iPolygonIsAllHorizontal;

   127 	TInt iFirstScanLine;

   128 	TInt iLastScanLine;

   129 	TInt iCurrentScanLine;

   130 	SFastData iFastData;

   131 	SSlowData iSlowData;

   132 private:

   133 	friend class TCompareEdgesUpperY;

   134 	friend class TCompareActiveEdgesFirstVertex;

   135 	friend class TCompareScanLineIntersectionsFirstPixel;

   136 	friend class TSwapEdges;

   137 	friend class TSwapActiveEdges;

   138 	friend class TSwapScanLineIntersections;

   139 	};

   140 

   141 #endif /*SWDIRECTGDIPOLYGON_H*/

   142