1 // Copyright 2016 PDFium Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4 
5 // Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
6 
7 #include "core/fxge/ge/cfx_cliprgn.h"
8 
CFX_ClipRgn(int width,int height)9 CFX_ClipRgn::CFX_ClipRgn(int width, int height)
10     : m_Type(RectI), m_Box(0, 0, width, height) {}
11 
CFX_ClipRgn(const CFX_ClipRgn & src)12 CFX_ClipRgn::CFX_ClipRgn(const CFX_ClipRgn& src) {
13   m_Type = src.m_Type;
14   m_Box = src.m_Box;
15   m_Mask = src.m_Mask;
16 }
17 
~CFX_ClipRgn()18 CFX_ClipRgn::~CFX_ClipRgn() {}
19 
Reset(const FX_RECT & rect)20 void CFX_ClipRgn::Reset(const FX_RECT& rect) {
21   m_Type = RectI;
22   m_Box = rect;
23   m_Mask.SetNull();
24 }
25 
IntersectRect(const FX_RECT & rect)26 void CFX_ClipRgn::IntersectRect(const FX_RECT& rect) {
27   if (m_Type == RectI) {
28     m_Box.Intersect(rect);
29     return;
30   }
31   if (m_Type == MaskF) {
32     IntersectMaskRect(rect, m_Box, m_Mask);
33     return;
34   }
35 }
36 
IntersectMaskRect(FX_RECT rect,FX_RECT mask_rect,CFX_DIBitmapRef Mask)37 void CFX_ClipRgn::IntersectMaskRect(FX_RECT rect,
38                                     FX_RECT mask_rect,
39                                     CFX_DIBitmapRef Mask) {
40   const CFX_DIBitmap* mask_dib = Mask.GetObject();
41   m_Type = MaskF;
42   m_Box = rect;
43   m_Box.Intersect(mask_rect);
44   if (m_Box.IsEmpty()) {
45     m_Type = RectI;
46     return;
47   }
48   if (m_Box == mask_rect) {
49     m_Mask = Mask;
50     return;
51   }
52   CFX_DIBitmap* new_dib = m_Mask.Emplace();
53   new_dib->Create(m_Box.Width(), m_Box.Height(), FXDIB_8bppMask);
54   for (int row = m_Box.top; row < m_Box.bottom; row++) {
55     uint8_t* dest_scan =
56         new_dib->GetBuffer() + new_dib->GetPitch() * (row - m_Box.top);
57     uint8_t* src_scan =
58         mask_dib->GetBuffer() + mask_dib->GetPitch() * (row - mask_rect.top);
59     for (int col = m_Box.left; col < m_Box.right; col++)
60       dest_scan[col - m_Box.left] = src_scan[col - mask_rect.left];
61   }
62 }
63 
IntersectMaskF(int left,int top,CFX_DIBitmapRef Mask)64 void CFX_ClipRgn::IntersectMaskF(int left, int top, CFX_DIBitmapRef Mask) {
65   const CFX_DIBitmap* mask_dib = Mask.GetObject();
66   ASSERT(mask_dib->GetFormat() == FXDIB_8bppMask);
67   FX_RECT mask_box(left, top, left + mask_dib->GetWidth(),
68                    top + mask_dib->GetHeight());
69   if (m_Type == RectI) {
70     IntersectMaskRect(m_Box, mask_box, Mask);
71     return;
72   }
73   if (m_Type == MaskF) {
74     FX_RECT new_box = m_Box;
75     new_box.Intersect(mask_box);
76     if (new_box.IsEmpty()) {
77       m_Type = RectI;
78       m_Mask.SetNull();
79       m_Box = new_box;
80       return;
81     }
82     CFX_DIBitmapRef new_mask;
83     CFX_DIBitmap* new_dib = new_mask.Emplace();
84     new_dib->Create(new_box.Width(), new_box.Height(), FXDIB_8bppMask);
85     const CFX_DIBitmap* old_dib = m_Mask.GetObject();
86     for (int row = new_box.top; row < new_box.bottom; row++) {
87       uint8_t* old_scan =
88           old_dib->GetBuffer() + (row - m_Box.top) * old_dib->GetPitch();
89       uint8_t* mask_scan =
90           mask_dib->GetBuffer() + (row - top) * mask_dib->GetPitch();
91       uint8_t* new_scan =
92           new_dib->GetBuffer() + (row - new_box.top) * new_dib->GetPitch();
93       for (int col = new_box.left; col < new_box.right; col++) {
94         new_scan[col - new_box.left] =
95             old_scan[col - m_Box.left] * mask_scan[col - left] / 255;
96       }
97     }
98     m_Box = new_box;
99     m_Mask = new_mask;
100     return;
101   }
102   ASSERT(false);
103 }
104