• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 // Copyright (c) 2011 The Chromium 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 #ifndef PDF_DRAW_UTILS_H_
6 #define PDF_DRAW_UTILS_H_
7 
8 #include <vector>
9 
10 #include "base/basictypes.h"
11 #include "ppapi/cpp/image_data.h"
12 #include "ppapi/cpp/rect.h"
13 
14 namespace chrome_pdf {
15 
16 const uint8 kOpaqueAlpha = 0xFF;
17 const uint8 kTransparentAlpha = 0x00;
18 
19 void AlphaBlend(const pp::ImageData& src, const pp::Rect& src_rc,
20                 pp::ImageData* dest, const pp::Point& dest_origin,
21                 uint8 alpha_adjustment);
22 
23 // Fill rectangle with gradient horizontally or vertically. Start is a color of
24 // top-left point of the rectangle, end color is a color of
25 // top-right (horizontal==true) or bottom-left (horizontal==false) point.
26 void GradientFill(pp::ImageData* image,
27                   const pp::Rect& rc,
28                   uint32 start_color,
29                   uint32 end_color,
30                   bool horizontal);
31 
32 // Fill dirty rectangle with gradient, where gradient color set for corners of
33 // gradient rectangle. Parts of the dirty rect outside of gradient rect will
34 // be unchanged.
35 void GradientFill(pp::Instance* instance,
36                   pp::ImageData* image,
37                   const pp::Rect& dirty_rc,
38                   const pp::Rect& gradient_rc,
39                   uint32 start_color,
40                   uint32 end_color,
41                   bool horizontal,
42                   uint8 transparency);
43 
44 // Copy one image into another. If stretch is true, the result occupy the entire
45 // dest_rc. If stretch is false, dest_rc.point will be used as an origin of the
46 // result image. Copy will ignore all pixels with transparent alpha from the
47 // source image.
48 void CopyImage(const pp::ImageData& src, const pp::Rect& src_rc,
49                pp::ImageData* dest, const pp::Rect& dest_rc,
50                bool stretch);
51 
52 // Fill in rectangle with specified color.
53 void FillRect(pp::ImageData* image, const pp::Rect& rc, uint32 color);
54 
55 // Shadow Matrix contains matrix for shadow rendering. To reduce amount of
56 // calculations user may choose to cache matrix and reuse it if nothing changed.
57 class ShadowMatrix {
58  public:
59   // Matrix parameters.
60   // depth - how big matrix should be. Shadow will go smoothly across the
61   // entire matrix from black to background color.
62   // If factor == 1, smoothing will be linear from 0 to the end (depth),
63   // if 0 < factor < 1, smoothing will drop faster near 0.
64   // if factor > 1, smoothing will drop faster near the end (depth).
65   ShadowMatrix(uint32 depth, double factor, uint32 background);
66 
67   ~ShadowMatrix();
68 
GetValue(int32 x,int32 y)69   uint32 GetValue(int32 x, int32 y) const { return matrix_[y * depth_ + x]; }
70 
depth()71   uint32 depth() const { return depth_; }
factor()72   double factor() const { return factor_; }
background()73   uint32 background() const { return background_; }
74 
75  private:
76   uint32 depth_;
77   double factor_;
78   uint32 background_;
79   std::vector<uint32> matrix_;
80 };
81 
82 // Draw shadow on the image using provided ShadowMatrix.
83 // shadow_rc - rectangle occupied by shadow
84 // object_rc - rectangle that drops the shadow
85 // clip_rc - clipping region
86 void DrawShadow(pp::ImageData* image,
87                 const pp::Rect& shadow_rc,
88                 const pp::Rect& object_rc,
89                 const pp::Rect& clip_rc,
90                 const ShadowMatrix& matrix);
91 
92 }  // namespace chrome_pdf
93 
94 #endif  // PDF_DRAW_UTILS_H_
95