agg/include/agg_rendering_buffer.h

302 lines
9.8 KiB
C++

//----------------------------------------------------------------------------
// Anti-Grain Geometry - Version 2.4
// Copyright (C) 2002-2005 Maxim Shemanarev (http://www.antigrain.com)
//
// Permission to copy, use, modify, sell and distribute this software
// is granted provided this copyright notice appears in all copies.
// This software is provided "as is" without express or implied
// warranty, and with no claim as to its suitability for any purpose.
//
//----------------------------------------------------------------------------
// Contact: mcseem@antigrain.com
// mcseemagg@yahoo.com
// http://www.antigrain.com
//----------------------------------------------------------------------------
//
// class rendering_buffer
//
//----------------------------------------------------------------------------
#ifndef AGG_RENDERING_BUFFER_INCLUDED
#define AGG_RENDERING_BUFFER_INCLUDED
#include <cstring>
#include "agg_array.h"
namespace agg
{
//===========================================================row_accessor
template<class T> class row_accessor
{
public:
typedef const_row_info<T> row_data;
//-------------------------------------------------------------------
row_accessor() :
m_buf(0),
m_start(0),
m_width(0),
m_height(0),
m_stride(0)
{
}
//--------------------------------------------------------------------
row_accessor(T* buf, unsigned width, unsigned height, int stride) :
m_buf(0),
m_start(0),
m_width(0),
m_height(0),
m_stride(0)
{
attach(buf, width, height, stride);
}
//--------------------------------------------------------------------
void attach(T* buf, unsigned width, unsigned height, int stride)
{
m_buf = m_start = buf;
m_width = width;
m_height = height;
m_stride = stride;
if(stride < 0)
{
m_start = m_buf - (AGG_INT64)(height - 1) * stride;
}
}
//--------------------------------------------------------------------
AGG_INLINE T* buf() { return m_buf; }
AGG_INLINE const T* buf() const { return m_buf; }
AGG_INLINE unsigned width() const { return m_width; }
AGG_INLINE unsigned height() const { return m_height; }
AGG_INLINE int stride() const { return m_stride; }
AGG_INLINE unsigned stride_abs() const
{
return (m_stride < 0) ? unsigned(-m_stride) : unsigned(m_stride);
}
//--------------------------------------------------------------------
AGG_INLINE T* row_ptr(int, int y, unsigned)
{
return m_start + y * (AGG_INT64)m_stride;
}
AGG_INLINE T* row_ptr(int y) { return m_start + y * (AGG_INT64)m_stride; }
AGG_INLINE const T* row_ptr(int y) const { return m_start + y * (AGG_INT64)m_stride; }
AGG_INLINE row_data row (int y) const
{
return row_data(0, m_width-1, row_ptr(y));
}
//--------------------------------------------------------------------
template<class RenBuf>
void copy_from(const RenBuf& src)
{
unsigned h = height();
if(src.height() < h) h = src.height();
unsigned l = stride_abs();
if(src.stride_abs() < l) l = src.stride_abs();
l *= sizeof(T);
unsigned y;
unsigned w = width();
for (y = 0; y < h; y++)
{
std::memcpy(row_ptr(0, y, w), src.row_ptr(y), l);
}
}
//--------------------------------------------------------------------
void clear(T value)
{
unsigned y;
unsigned w = width();
unsigned stride = stride_abs();
for(y = 0; y < height(); y++)
{
T* p = row_ptr(0, y, w);
unsigned x;
for(x = 0; x < stride; x++)
{
*p++ = value;
}
}
}
private:
//--------------------------------------------------------------------
T* m_buf; // Pointer to renrdering buffer
T* m_start; // Pointer to first pixel depending on stride
unsigned m_width; // Width in pixels
unsigned m_height; // Height in pixels
int m_stride; // Number of bytes per row. Can be < 0
};
//==========================================================row_ptr_cache
template<class T> class row_ptr_cache
{
public:
typedef const_row_info<T> row_data;
//-------------------------------------------------------------------
row_ptr_cache() :
m_buf(0),
m_rows(),
m_width(0),
m_height(0),
m_stride(0)
{
}
//--------------------------------------------------------------------
row_ptr_cache(T* buf, unsigned width, unsigned height, int stride) :
m_buf(0),
m_rows(),
m_width(0),
m_height(0),
m_stride(0)
{
attach(buf, width, height, stride);
}
//--------------------------------------------------------------------
void attach(T* buf, unsigned width, unsigned height, int stride)
{
m_buf = buf;
m_width = width;
m_height = height;
m_stride = stride;
if(height > m_rows.size())
{
m_rows.resize(height);
}
T* row_ptr = m_buf;
if(stride < 0)
{
row_ptr = m_buf - (AGG_INT64)(height - 1) * stride;
}
T** rows = &m_rows[0];
while(height--)
{
*rows++ = row_ptr;
row_ptr += stride;
}
}
//--------------------------------------------------------------------
AGG_INLINE T* buf() { return m_buf; }
AGG_INLINE const T* buf() const { return m_buf; }
AGG_INLINE unsigned width() const { return m_width; }
AGG_INLINE unsigned height() const { return m_height; }
AGG_INLINE int stride() const { return m_stride; }
AGG_INLINE unsigned stride_abs() const
{
return (m_stride < 0) ? unsigned(-m_stride) : unsigned(m_stride);
}
//--------------------------------------------------------------------
AGG_INLINE T* row_ptr(int, int y, unsigned)
{
return m_rows[y];
}
AGG_INLINE T* row_ptr(int y) { return m_rows[y]; }
AGG_INLINE const T* row_ptr(int y) const { return m_rows[y]; }
AGG_INLINE row_data row (int y) const
{
return row_data(0, m_width-1, m_rows[y]);
}
//--------------------------------------------------------------------
T const* const* rows() const { return &m_rows[0]; }
//--------------------------------------------------------------------
template<class RenBuf>
void copy_from(const RenBuf& src)
{
unsigned h = height();
if(src.height() < h) h = src.height();
unsigned l = stride_abs();
if(src.stride_abs() < l) l = src.stride_abs();
l *= sizeof(T);
unsigned y;
unsigned w = width();
for (y = 0; y < h; y++)
{
std::memcpy(row_ptr(0, y, w), src.row_ptr(y), l);
}
}
//--------------------------------------------------------------------
void clear(T value)
{
unsigned y;
unsigned w = width();
unsigned stride = stride_abs();
for(y = 0; y < height(); y++)
{
T* p = row_ptr(0, y, w);
unsigned x;
for(x = 0; x < stride; x++)
{
*p++ = value;
}
}
}
private:
//--------------------------------------------------------------------
T* m_buf; // Pointer to renrdering buffer
pod_array<T*> m_rows; // Pointers to each row of the buffer
unsigned m_width; // Width in pixels
unsigned m_height; // Height in pixels
int m_stride; // Number of bytes per row. Can be < 0
};
//========================================================rendering_buffer
//
// The definition of the main type for accessing the rows in the frame
// buffer. It provides functionality to navigate to the rows in a
// rectangular matrix, from top to bottom or from bottom to top depending
// on stride.
//
// row_accessor is cheap to create/destroy, but performs one multiplication
// when calling row_ptr().
//
// row_ptr_cache creates an array of pointers to rows, so, the access
// via row_ptr() may be faster. But it requires memory allocation
// when creating. For example, on typical Intel Pentium hardware
// row_ptr_cache speeds span_image_filter_rgb_nn up to 10%
//
// It's used only in short hand typedefs like pixfmt_rgba32 and can be
// redefined in agg_config.h
// In real applications you can use both, depending on your needs
//------------------------------------------------------------------------
#ifdef AGG_RENDERING_BUFFER
typedef AGG_RENDERING_BUFFER rendering_buffer;
#else
// typedef row_ptr_cache<int8u> rendering_buffer;
typedef row_accessor<int8u> rendering_buffer;
#endif
}
#endif