1
2/*
3 * Copyright 2006 The Android Open Source Project
4 *
5 * Use of this source code is governed by a BSD-style license that can be
6 * found in the LICENSE file.
7 */
8
9
10#ifndef SkDraw_DEFINED
11#define SkDraw_DEFINED
12
13#include "SkCanvas.h"
14#include "SkMask.h"
15#include "SkPaint.h"
16
17class SkBitmap;
18class SkBounder;
19class SkClipStack;
20class SkDevice;
21class SkMatrix;
22class SkPath;
23class SkRegion;
24class SkRasterClip;
25struct SkDrawProcs;
26struct SkRect;
27
28class SkDraw {
29public:
30    SkDraw();
31    SkDraw(const SkDraw& src);
32
33    void    drawPaint(const SkPaint&) const;
34    void    drawPoints(SkCanvas::PointMode, size_t count, const SkPoint[],
35                       const SkPaint&, bool forceUseDevice = false) const;
36    void    drawRect(const SkRect&, const SkPaint&) const;
37    /**
38     *  To save on mallocs, we allow a flag that tells us that srcPath is
39     *  mutable, so that we don't have to make copies of it as we transform it.
40     *
41     *  If prePathMatrix is not null, it should logically be applied before any
42     *  stroking or other effects. If there are no effects on the paint that
43     *  affect the geometry/rasterization, then the pre matrix can just be
44     *  pre-concated with the current matrix.
45     */
46    void    drawPath(const SkPath& srcPath, const SkPaint&,
47                     const SkMatrix* prePathMatrix, bool pathIsMutable) const;
48    void    drawBitmap(const SkBitmap&, const SkMatrix&, const SkPaint&) const;
49    void    drawSprite(const SkBitmap&, int x, int y, const SkPaint&) const;
50    void    drawText(const char text[], size_t byteLength, SkScalar x,
51                     SkScalar y, const SkPaint& paint) const;
52    void    drawPosText(const char text[], size_t byteLength,
53                        const SkScalar pos[], SkScalar constY,
54                        int scalarsPerPosition, const SkPaint& paint) const;
55    void    drawTextOnPath(const char text[], size_t byteLength,
56                        const SkPath&, const SkMatrix*, const SkPaint&) const;
57#ifdef SK_BUILD_FOR_ANDROID
58    void    drawPosTextOnPath(const char text[], size_t byteLength,
59                              const SkPoint pos[], const SkPaint& paint,
60                              const SkPath& path, const SkMatrix* matrix) const;
61#endif
62    void    drawVertices(SkCanvas::VertexMode mode, int count,
63                         const SkPoint vertices[], const SkPoint textures[],
64                         const SkColor colors[], SkXfermode* xmode,
65                         const uint16_t indices[], int ptCount,
66                         const SkPaint& paint) const;
67
68    void drawPath(const SkPath& src, const SkPaint& paint) const {
69        this->drawPath(src, paint, NULL, false);
70    }
71
72    /** Helper function that creates a mask from a path and an optional maskfilter.
73        Note however, that the resulting mask will not have been actually filtered,
74        that must be done afterwards (by calling filterMask). The maskfilter is provided
75        solely to assist in computing the mask's bounds (if the mode requests that).
76    */
77    static bool DrawToMask(const SkPath& devPath, const SkIRect* clipBounds,
78                           const SkMaskFilter*, const SkMatrix* filterMatrix,
79                           SkMask* mask, SkMask::CreateMode mode,
80                           SkPaint::Style style);
81
82    enum RectType {
83        kHair_RectType,
84        kFill_RectType,
85        kStroke_RectType,
86        kPath_RectType
87    };
88
89    /**
90     *  Based on the paint's style, strokeWidth, and the matrix, classify how
91     *  to draw the rect. If no special-case is available, returns
92     *  kPath_RectType.
93     *
94     *  Iff RectType == kStroke_RectType, then strokeSize is set to the device
95     *  width and height of the stroke.
96     */
97    static RectType ComputeRectType(const SkPaint&, const SkMatrix&,
98                                    SkPoint* strokeSize);
99
100private:
101    void    drawText_asPaths(const char text[], size_t byteLength,
102                             SkScalar x, SkScalar y, const SkPaint&) const;
103    void    drawDevMask(const SkMask& mask, const SkPaint&) const;
104    void    drawBitmapAsMask(const SkBitmap&, const SkPaint&) const;
105
106    void    drawPosText_asPaths(const char text[], size_t byteLength,
107                                const SkScalar pos[], SkScalar constY,
108                                int scalarsPerPosition, const SkPaint&) const;
109
110    /**
111     *  Return the current clip bounds, in local coordinates, with slop to account
112     *  for antialiasing or hairlines (i.e. device-bounds outset by 1, and then
113     *  run through the inverse of the matrix).
114     *
115     *  If the matrix cannot be inverted, or the current clip is empty, return
116     *  false and ignore bounds parameter.
117     */
118    bool SK_WARN_UNUSED_RESULT
119    computeConservativeLocalClipBounds(SkRect* bounds) const;
120
121    static bool ShouldDrawTextAsPaths(const SkPaint&, const SkMatrix&);
122
123public:
124    const SkBitmap* fBitmap;        // required
125    const SkMatrix* fMatrix;        // required
126    const SkRegion* fClip;          // DEPRECATED
127    const SkRasterClip* fRC;        // required
128
129    const SkClipStack* fClipStack;  // optional
130    SkDevice*       fDevice;        // optional
131    SkBounder*      fBounder;       // optional
132    SkDrawProcs*    fProcs;         // optional
133
134#ifdef SK_DEBUG
135    void validate() const;
136#else
137    void validate() const {}
138#endif
139};
140
141#endif
142