xref: /haiku/headers/libs/agg/agg_rendering_buffer.h (revision e39da397f5ff79f2db9f9a3ddf1852b6710578af)
1 //----------------------------------------------------------------------------
2 // Anti-Grain Geometry - Version 2.4
3 // Copyright (C) 2002-2005 Maxim Shemanarev (http://www.antigrain.com)
4 //
5 // Permission to copy, use, modify, sell and distribute this software
6 // is granted provided this copyright notice appears in all copies.
7 // This software is provided "as is" without express or implied
8 // warranty, and with no claim as to its suitability for any purpose.
9 //
10 //----------------------------------------------------------------------------
11 // Contact: mcseem@antigrain.com
12 //          mcseemagg@yahoo.com
13 //          http://www.antigrain.com
14 //----------------------------------------------------------------------------
15 //
16 // class rendering_buffer
17 //
18 //----------------------------------------------------------------------------
19 
20 #ifndef AGG_RENDERING_BUFFER_INCLUDED
21 #define AGG_RENDERING_BUFFER_INCLUDED
22 
23 #include "agg_array.h"
24 
25 namespace agg
26 {
27 
28     //==========================================================row_ptr_cache
29     template<class T> class row_ptr_cache
30     {
31     public:
32         //--------------------------------------------------------------------
33         struct row_data
34         {
35             int x1, x2;
36             const int8u* ptr;
row_datarow_data37             row_data() {}
row_datarow_data38             row_data(int x1_, int x2_, const int8u* ptr_) :
39                 x1(x1_), x2(x2_), ptr(ptr_) {}
40         };
41 
42         //-------------------------------------------------------------------
row_ptr_cache()43         row_ptr_cache() :
44             m_buf(0),
45             m_rows(),
46             m_width(0),
47             m_height(0),
48             m_stride(0)
49         {
50         }
51 
52         //--------------------------------------------------------------------
row_ptr_cache(T * buf,unsigned width,unsigned height,int stride)53         row_ptr_cache(T* buf, unsigned width, unsigned height, int stride) :
54             m_buf(0),
55             m_rows(),
56             m_width(0),
57             m_height(0),
58             m_stride(0)
59         {
60             attach(buf, width, height, stride);
61         }
62 
63         //--------------------------------------------------------------------
attach(T * buf,unsigned width,unsigned height,int stride)64         void attach(T* buf, unsigned width, unsigned height, int stride)
65         {
66             m_buf = buf;
67             m_width = width;
68             m_height = height;
69             m_stride = stride;
70             if(height > m_rows.size())
71             {
72                 m_rows.resize(height);
73             }
74 
75             T* row_ptr = m_buf;
76 
77             if(stride < 0)
78             {
79                 row_ptr = m_buf - int(height - 1) * stride;
80             }
81 
82             T** rows = &m_rows[0];
83 
84             while(height--)
85             {
86                 *rows++ = row_ptr;
87                 row_ptr += stride;
88             }
89         }
90 
91         //--------------------------------------------------------------------
buf()92               T* buf()          { return m_buf;    }
buf()93         const T* buf()    const { return m_buf;    }
width()94         unsigned width()  const { return m_width;  }
height()95         unsigned height() const { return m_height; }
stride()96         int      stride() const { return m_stride; }
stride_abs()97         unsigned stride_abs() const
98         {
99             return (m_stride < 0) ? unsigned(-m_stride) : unsigned(m_stride);
100         }
101 
102         //--------------------------------------------------------------------
row_ptr(int,int y,unsigned)103               T* row_ptr(int, int y, unsigned) { return m_rows[y]; }
row_ptr(int y)104               T* row_ptr(int y)                { return m_rows[y]; }
row_ptr(int y)105         const T* row_ptr(int y) const          { return m_rows[y]; }
row(int y)106         row_data row    (int y) const { return row_data(0, m_width-1, m_rows[y]); }
107 
108         //--------------------------------------------------------------------
rows()109         T const* const* rows() const { return &m_rows[0]; }
110 
111         //--------------------------------------------------------------------
112         template<class RenBuf>
copy_from(const RenBuf & src)113         void copy_from(const RenBuf& src)
114         {
115             unsigned h = height();
116             if(src.height() < h) h = src.height();
117 
118             unsigned l = stride_abs();
119             if(src.stride_abs() < l) l = src.stride_abs();
120 
121             l *= sizeof(T);
122 
123             unsigned y;
124             unsigned w = width();
125             for (y = 0; y < h; y++)
126             {
127                 memcpy(row_ptr(0, y, w), src.row_ptr(y), l);
128             }
129         }
130 
131         //--------------------------------------------------------------------
clear(T value)132         void clear(T value)
133         {
134             unsigned y;
135             unsigned w = width();
136             unsigned stride = stride_abs();
137             for(y = 0; y < height(); y++)
138             {
139                 T* p = row_ptr(0, y, w);
140                 unsigned x;
141                 for(x = 0; x < stride; x++)
142                 {
143                     *p++ = value;
144                 }
145             }
146         }
147 
148     private:
149         //--------------------------------------------------------------------
150         T*            m_buf;        // Pointer to renrdering buffer
151         pod_array<T*> m_rows;       // Pointers to each row of the buffer
152         unsigned      m_width;      // Width in pixels
153         unsigned      m_height;     // Height in pixels
154         int           m_stride;     // Number of bytes per row. Can be < 0
155     };
156 
157 
158 
159     //========================================================rendering_buffer
160     typedef row_ptr_cache<int8u> rendering_buffer;
161 
162 }
163 
164 
165 #endif
166