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;
27class SkRRect;
28
29class SkDraw {
30public:
31    SkDraw();
32    SkDraw(const SkDraw& src);
33
34    void    drawPaint(const SkPaint&) const;
35    void    drawPoints(SkCanvas::PointMode, size_t count, const SkPoint[],
36                       const SkPaint&, bool forceUseDevice = false) const;
37    void    drawRect(const SkRect&, const SkPaint&) const;
38    void    drawRRect(const SkRRect&, const SkPaint&) const;
39    /**
40     *  To save on mallocs, we allow a flag that tells us that srcPath is
41     *  mutable, so that we don't have to make copies of it as we transform it.
42     *
43     *  If prePathMatrix is not null, it should logically be applied before any
44     *  stroking or other effects. If there are no effects on the paint that
45     *  affect the geometry/rasterization, then the pre matrix can just be
46     *  pre-concated with the current matrix.
47     */
48    void    drawPath(const SkPath& srcPath, const SkPaint&,
49                     const SkMatrix* prePathMatrix, bool pathIsMutable) const;
50    void    drawBitmap(const SkBitmap&, const SkMatrix&, const SkPaint&) const;
51    void    drawSprite(const SkBitmap&, int x, int y, const SkPaint&) const;
52    void    drawText(const char text[], size_t byteLength, SkScalar x,
53                     SkScalar y, const SkPaint& paint) const;
54    void    drawPosText(const char text[], size_t byteLength,
55                        const SkScalar pos[], SkScalar constY,
56                        int scalarsPerPosition, const SkPaint& paint) const;
57    void    drawTextOnPath(const char text[], size_t byteLength,
58                        const SkPath&, const SkMatrix*, const SkPaint&) const;
59#ifdef SK_BUILD_FOR_ANDROID
60    void    drawPosTextOnPath(const char text[], size_t byteLength,
61                              const SkPoint pos[], const SkPaint& paint,
62                              const SkPath& path, const SkMatrix* matrix) const;
63#endif
64    void    drawVertices(SkCanvas::VertexMode mode, int count,
65                         const SkPoint vertices[], const SkPoint textures[],
66                         const SkColor colors[], SkXfermode* xmode,
67                         const uint16_t indices[], int ptCount,
68                         const SkPaint& paint) const;
69
70    void drawPath(const SkPath& src, const SkPaint& paint) const {
71        this->drawPath(src, paint, NULL, false);
72    }
73
74    /** Helper function that creates a mask from a path and an optional maskfilter.
75        Note however, that the resulting mask will not have been actually filtered,
76        that must be done afterwards (by calling filterMask). The maskfilter is provided
77        solely to assist in computing the mask's bounds (if the mode requests that).
78    */
79    static bool DrawToMask(const SkPath& devPath, const SkIRect* clipBounds,
80                           const SkMaskFilter*, const SkMatrix* filterMatrix,
81                           SkMask* mask, SkMask::CreateMode mode,
82                           SkPaint::Style style);
83
84    enum RectType {
85        kHair_RectType,
86        kFill_RectType,
87        kStroke_RectType,
88        kPath_RectType
89    };
90
91    /**
92     *  Based on the paint's style, strokeWidth, and the matrix, classify how
93     *  to draw the rect. If no special-case is available, returns
94     *  kPath_RectType.
95     *
96     *  Iff RectType == kStroke_RectType, then strokeSize is set to the device
97     *  width and height of the stroke.
98     */
99    static RectType ComputeRectType(const SkPaint&, const SkMatrix&,
100                                    SkPoint* strokeSize);
101
102    void    drawText_asPaths(const char text[], size_t byteLength,
103                             SkScalar x, SkScalar y, const SkPaint&) const;
104    void    drawPosText_asPaths(const char text[], size_t byteLength,
105                                const SkScalar pos[], SkScalar constY,
106                                int scalarsPerPosition, const SkPaint&) const;
107
108private:
109    void    drawDevMask(const SkMask& mask, const SkPaint&) const;
110    void    drawBitmapAsMask(const SkBitmap&, const SkPaint&) const;
111
112    /**
113     *  Return the current clip bounds, in local coordinates, with slop to account
114     *  for antialiasing or hairlines (i.e. device-bounds outset by 1, and then
115     *  run through the inverse of the matrix).
116     *
117     *  If the matrix cannot be inverted, or the current clip is empty, return
118     *  false and ignore bounds parameter.
119     */
120    bool SK_WARN_UNUSED_RESULT
121    computeConservativeLocalClipBounds(SkRect* bounds) const;
122
123    static bool ShouldDrawTextAsPaths(const SkPaint&, const SkMatrix&);
124
125public:
126    const SkBitmap* fBitmap;        // required
127    const SkMatrix* fMatrix;        // required
128    const SkRegion* fClip;          // DEPRECATED
129    const SkRasterClip* fRC;        // required
130
131    const SkClipStack* fClipStack;  // optional
132    SkDevice*       fDevice;        // optional
133    SkBounder*      fBounder;       // optional
134    SkDrawProcs*    fProcs;         // optional
135
136#ifdef SK_DEBUG
137    void validate() const;
138#else
139    void validate() const {}
140#endif
141};
142
143#endif
144