• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 /*
2  * Copyright 2006 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 #include "SkBitmap.h"
10 #include "SkMask.h"
11 
12 #ifndef ClearLow3Bits_DEFINED
13 #define ClearLow3Bits_DEFINED
14     #define ClearLow3Bits(x)    ((unsigned)(x) >> 3 << 3)
15 #endif
16 
17 /*
18     SK_BLITBWMASK_NAME          name of function(const SkBitmap& bitmap, const SkMask& mask, const SkIRect& clip, SK_BLITBWMASK_ARGS)
19     SK_BLITBWMASK_ARGS          list of additional arguments to SK_BLITBWMASK_NAME, beginning with a comma
20     SK_BLITBWMASK_BLIT8         name of function(U8CPU byteMask, SK_BLITBWMASK_DEVTYPE* dst, int x, int y)
21     SK_BLITBWMASK_GETADDR       either writable_addr[8,16,32]
22     SK_BLITBWMASK_DEVTYPE       either U32 or U16 or U8
23 */
24 
SK_BLITBWMASK_NAME(const SkPixmap & dst,const SkMask & srcMask,const SkIRect & clip SK_BLITBWMASK_ARGS)25 static void SK_BLITBWMASK_NAME(const SkPixmap& dst, const SkMask& srcMask,
26                                const SkIRect& clip SK_BLITBWMASK_ARGS) {
27     SkASSERT(clip.fRight <= srcMask.fBounds.fRight);
28 
29     int cx = clip.fLeft;
30     int cy = clip.fTop;
31     int maskLeft = srcMask.fBounds.fLeft;
32     unsigned mask_rowBytes = srcMask.fRowBytes;
33     size_t bitmap_rowBytes = dst.rowBytes();
34     unsigned height = clip.height();
35 
36     SkASSERT(mask_rowBytes != 0);
37     SkASSERT(bitmap_rowBytes != 0);
38     SkASSERT(height != 0);
39 
40     const uint8_t* bits = srcMask.getAddr1(cx, cy);
41     SK_BLITBWMASK_DEVTYPE* device = dst.SK_BLITBWMASK_GETADDR(cx, cy);
42 
43     if (cx == maskLeft && clip.fRight == srcMask.fBounds.fRight)
44     {
45         do {
46             SK_BLITBWMASK_DEVTYPE* dst = device;
47             unsigned rb = mask_rowBytes;
48             do {
49                 U8CPU mask = *bits++;
50                 SK_BLITBWMASK_BLIT8(mask, dst);
51                 dst += 8;
52             } while (--rb != 0);
53             device = (SK_BLITBWMASK_DEVTYPE*)((char*)device + bitmap_rowBytes);
54         } while (--height != 0);
55     }
56     else
57     {
58         int left_edge = cx - maskLeft;
59         SkASSERT(left_edge >= 0);
60         int rite_edge = clip.fRight - maskLeft;
61         SkASSERT(rite_edge > left_edge);
62 
63         int left_mask = 0xFF >> (left_edge & 7);
64         int rite_mask = 0xFF << (8 - (rite_edge & 7));
65         rite_mask &= 0xFF;  // only want low-8 bits of mask
66         int full_runs = (rite_edge >> 3) - ((left_edge + 7) >> 3);
67 
68         // check for empty right mask, so we don't read off the end (or go slower than we need to)
69         if (rite_mask == 0)
70         {
71             SkASSERT(full_runs >= 0);
72             full_runs -= 1;
73             rite_mask = 0xFF;
74         }
75         if (left_mask == 0xFF)
76             full_runs -= 1;
77 
78         // back up manually so we can keep in sync with our byte-aligned src
79         // and not trigger an assert from the getAddr## function
80         device -= left_edge & 7;
81 
82         if (full_runs < 0)
83         {
84             left_mask &= rite_mask;
85             SkASSERT(left_mask != 0);
86             do {
87                 U8CPU mask = *bits & left_mask;
88                 SK_BLITBWMASK_BLIT8(mask, device);
89                 bits += mask_rowBytes;
90                 device = (SK_BLITBWMASK_DEVTYPE*)((char*)device + bitmap_rowBytes);
91             } while (--height != 0);
92         }
93         else
94         {
95             do {
96                 int runs = full_runs;
97                 SK_BLITBWMASK_DEVTYPE* dst = device;
98                 const uint8_t* b = bits;
99                 U8CPU   mask;
100 
101                 mask = *b++ & left_mask;
102                 SK_BLITBWMASK_BLIT8(mask, dst);
103                 dst += 8;
104 
105                 while (--runs >= 0)
106                 {
107                     mask = *b++;
108                     SK_BLITBWMASK_BLIT8(mask, dst);
109                     dst += 8;
110                 }
111 
112                 mask = *b & rite_mask;
113                 SK_BLITBWMASK_BLIT8(mask, dst);
114 
115                 bits += mask_rowBytes;
116                 device = (SK_BLITBWMASK_DEVTYPE*)((char*)device + bitmap_rowBytes);
117             } while (--height != 0);
118         }
119     }
120 }
121 
122 #undef SK_BLITBWMASK_NAME
123 #undef SK_BLITBWMASK_ARGS
124 #undef SK_BLITBWMASK_BLIT8
125 #undef SK_BLITBWMASK_GETADDR
126 #undef SK_BLITBWMASK_DEVTYPE
127 #undef SK_BLITBWMASK_DOROWSETUP
128