1 /*
2  * Copyright 2011 The Android Open Source Project
3  *
4  * Use of this source code is governed by a BSD-style license that can be
5  * found in the LICENSE file.
6  */
7 
8 
9 #ifndef SkScan_DEFINED
10 #define SkScan_DEFINED
11 
12 #include "SkFixed.h"
13 #include "SkRect.h"
14 #include <atomic>
15 
16 class SkRasterClip;
17 class SkRegion;
18 class SkBlitter;
19 class SkPath;
20 
21 /** Defines a fixed-point rectangle, identical to the integer SkIRect, but its
22     coordinates are treated as SkFixed rather than int32_t.
23 */
24 typedef SkIRect SkXRect;
25 
26 extern std::atomic<bool> gSkUseAnalyticAA;
27 extern std::atomic<bool> gSkForceAnalyticAA;
28 
29 class AdditiveBlitter;
30 
31 class SkScan {
32 public:
33     /*
34      *  Draws count-1 line segments, one at a time:
35      *      line(pts[0], pts[1])
36      *      line(pts[1], pts[2])
37      *      line(......, pts[count - 1])
38      */
39     typedef void (*HairRgnProc)(const SkPoint[], int count, const SkRegion*, SkBlitter*);
40     typedef void (*HairRCProc)(const SkPoint[], int count, const SkRasterClip&, SkBlitter*);
41 
42     static void FillPath(const SkPath&, const SkIRect&, SkBlitter*);
43 
44     ///////////////////////////////////////////////////////////////////////////
45     // rasterclip
46 
47     static void FillIRect(const SkIRect&, const SkRasterClip&, SkBlitter*);
48     static void FillXRect(const SkXRect&, const SkRasterClip&, SkBlitter*);
49     static void FillRect(const SkRect&, const SkRasterClip&, SkBlitter*);
50     static void AntiFillRect(const SkRect&, const SkRasterClip&, SkBlitter*);
51     static void AntiFillXRect(const SkXRect&, const SkRasterClip&, SkBlitter*);
52     static void FillPath(const SkPath&, const SkRasterClip&, SkBlitter*);
53     static void AntiFillPath(const SkPath&, const SkRasterClip&, SkBlitter*);
54     static void AAAFillPath(const SkPath&, const SkRasterClip&, SkBlitter*);
55     static void FrameRect(const SkRect&, const SkPoint& strokeSize,
56                           const SkRasterClip&, SkBlitter*);
57     static void AntiFrameRect(const SkRect&, const SkPoint& strokeSize,
58                               const SkRasterClip&, SkBlitter*);
59     static void FillTriangle(const SkPoint pts[], const SkRasterClip&, SkBlitter*);
60     static void HairLine(const SkPoint[], int count, const SkRasterClip&, SkBlitter*);
61     static void AntiHairLine(const SkPoint[], int count, const SkRasterClip&, SkBlitter*);
62     static void HairRect(const SkRect&, const SkRasterClip&, SkBlitter*);
63     static void AntiHairRect(const SkRect&, const SkRasterClip&, SkBlitter*);
64     static void HairPath(const SkPath&, const SkRasterClip&, SkBlitter*);
65     static void AntiHairPath(const SkPath&, const SkRasterClip&, SkBlitter*);
66     static void HairSquarePath(const SkPath&, const SkRasterClip&, SkBlitter*);
67     static void AntiHairSquarePath(const SkPath&, const SkRasterClip&, SkBlitter*);
68     static void HairRoundPath(const SkPath&, const SkRasterClip&, SkBlitter*);
69     static void AntiHairRoundPath(const SkPath&, const SkRasterClip&, SkBlitter*);
70 
71 private:
72     friend class SkAAClip;
73     friend class SkRegion;
74 
75     static void FillIRect(const SkIRect&, const SkRegion* clip, SkBlitter*);
76     static void FillXRect(const SkXRect&, const SkRegion* clip, SkBlitter*);
77     static void FillRect(const SkRect&, const SkRegion* clip, SkBlitter*);
78     static void AntiFillRect(const SkRect&, const SkRegion* clip, SkBlitter*);
79     static void AntiFillXRect(const SkXRect&, const SkRegion*, SkBlitter*);
80     static void FillPath(const SkPath&, const SkRegion& clip, SkBlitter*);
81     static void AntiFillPath(const SkPath&, const SkRegion& clip, SkBlitter*,
82                              bool forceRLE = false);
83     static void FillTriangle(const SkPoint pts[], const SkRegion*, SkBlitter*);
84 
85     static void AntiFrameRect(const SkRect&, const SkPoint& strokeSize,
86                               const SkRegion*, SkBlitter*);
87     static void HairLineRgn(const SkPoint[], int count, const SkRegion*, SkBlitter*);
88     static void AntiHairLineRgn(const SkPoint[], int count, const SkRegion*, SkBlitter*);
89     static void AAAFillPath(const SkPath& path, const SkRegion& origClip, SkBlitter* blitter,
90                             bool forceRLE = false); // SkAAClip uses forceRLE
91 };
92 
93 /** Assign an SkXRect from a SkIRect, by promoting the src rect's coordinates
94     from int to SkFixed. Does not check for overflow if the src coordinates
95     exceed 32K
96 */
XRect_set(SkXRect * xr,const SkIRect & src)97 static inline void XRect_set(SkXRect* xr, const SkIRect& src) {
98     xr->fLeft = SkIntToFixed(src.fLeft);
99     xr->fTop = SkIntToFixed(src.fTop);
100     xr->fRight = SkIntToFixed(src.fRight);
101     xr->fBottom = SkIntToFixed(src.fBottom);
102 }
103 
104 /** Assign an SkXRect from a SkRect, by promoting the src rect's coordinates
105     from SkScalar to SkFixed. Does not check for overflow if the src coordinates
106     exceed 32K
107 */
XRect_set(SkXRect * xr,const SkRect & src)108 static inline void XRect_set(SkXRect* xr, const SkRect& src) {
109     xr->fLeft = SkScalarToFixed(src.fLeft);
110     xr->fTop = SkScalarToFixed(src.fTop);
111     xr->fRight = SkScalarToFixed(src.fRight);
112     xr->fBottom = SkScalarToFixed(src.fBottom);
113 }
114 
115 /** Round the SkXRect coordinates, and store the result in the SkIRect.
116 */
XRect_round(const SkXRect & xr,SkIRect * dst)117 static inline void XRect_round(const SkXRect& xr, SkIRect* dst) {
118     dst->fLeft = SkFixedRoundToInt(xr.fLeft);
119     dst->fTop = SkFixedRoundToInt(xr.fTop);
120     dst->fRight = SkFixedRoundToInt(xr.fRight);
121     dst->fBottom = SkFixedRoundToInt(xr.fBottom);
122 }
123 
124 /** Round the SkXRect coordinates out (i.e. use floor for left/top, and ceiling
125     for right/bottom), and store the result in the SkIRect.
126 */
XRect_roundOut(const SkXRect & xr,SkIRect * dst)127 static inline void XRect_roundOut(const SkXRect& xr, SkIRect* dst) {
128     dst->fLeft = SkFixedFloorToInt(xr.fLeft);
129     dst->fTop = SkFixedFloorToInt(xr.fTop);
130     dst->fRight = SkFixedCeilToInt(xr.fRight);
131     dst->fBottom = SkFixedCeilToInt(xr.fBottom);
132 }
133 
134 #endif
135