Files
processing4/agg/agg_span_image_resample_gray.h
2006-04-07 23:56:49 +00:00

360 lines
14 KiB
C++

//----------------------------------------------------------------------------
// Anti-Grain Geometry - Version 2.3
// 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
//----------------------------------------------------------------------------
#ifndef AGG_SPAN_IMAGE_RESAMPLE_GRAY_INCLUDED
#define AGG_SPAN_IMAGE_RESAMPLE_GRAY_INCLUDED
#include "agg_color_gray.h"
#include "agg_span_image_resample.h"
namespace agg
{
//========================================span_image_resample_gray_affine
template<class ColorT,
class Allocator = span_allocator<ColorT> >
class span_image_resample_gray_affine :
public span_image_resample_affine<ColorT, Allocator>
{
public:
typedef ColorT color_type;
typedef Allocator alloc_type;
typedef span_image_resample_affine<color_type, alloc_type> base_type;
typedef typename base_type::interpolator_type interpolator_type;
typedef typename color_type::value_type value_type;
typedef typename color_type::long_type long_type;
enum base_scale_e
{
base_shift = color_type::base_shift,
base_mask = color_type::base_mask,
downscale_shift = image_filter_shift
};
//--------------------------------------------------------------------
span_image_resample_gray_affine(alloc_type& alloc) : base_type(alloc) {}
//--------------------------------------------------------------------
span_image_resample_gray_affine(alloc_type& alloc,
const rendering_buffer& src,
const color_type& back_color,
interpolator_type& inter,
const image_filter_lut& filter) :
base_type(alloc, src, back_color, inter, filter)
{}
//--------------------------------------------------------------------
color_type* generate(int x, int y, unsigned len)
{
base_type::interpolator().begin(x + base_type::filter_dx_dbl(),
y + base_type::filter_dy_dbl(), len);
long_type fg;
long_type src_alpha;
value_type back_v = base_type::background_color().v;
value_type back_a = base_type::background_color().a;
color_type* span = base_type::allocator().span();
int diameter = base_type::filter().diameter();
int filter_size = diameter << image_subpixel_shift;
int radius_x = (diameter * base_type::m_rx) >> 1;
int radius_y = (diameter * base_type::m_ry) >> 1;
int maxx = base_type::source_image().width() - 1;
int maxy = base_type::source_image().height() - 1;
const int16* weight_array = base_type::filter().weight_array();
do
{
base_type::interpolator().coordinates(&x, &y);
x += base_type::filter_dx_int() - radius_x;
y += base_type::filter_dy_int() - radius_y;
fg = src_alpha = image_filter_size / 2;
int y_lr = y >> image_subpixel_shift;
int y_hr = ((image_subpixel_mask - (y & image_subpixel_mask)) *
base_type::m_ry_inv) >>
image_subpixel_shift;
int total_weight = 0;
int x_lr_ini = x >> image_subpixel_shift;
int x_hr_ini = ((image_subpixel_mask - (x & image_subpixel_mask)) *
base_type::m_rx_inv) >>
image_subpixel_shift;
do
{
int weight_y = weight_array[y_hr];
int x_lr = x_lr_ini;
int x_hr = x_hr_ini;
if(y_lr >= 0 && y_lr <= maxy)
{
const value_type* fg_ptr = (const value_type*)
base_type::source_image().row(y_lr) + x_lr;
do
{
int weight = (weight_y * weight_array[x_hr] +
image_filter_size / 2) >>
downscale_shift;
if(x_lr >= 0 && x_lr <= maxx)
{
fg += *fg_ptr * weight;
src_alpha += base_mask * weight;
}
else
{
fg += back_v * weight;
src_alpha += back_a * weight;
}
total_weight += weight;
x_hr += base_type::m_rx_inv;
++fg_ptr;
++x_lr;
}
while(x_hr < filter_size);
}
else
{
do
{
int weight = (weight_y * weight_array[x_hr] +
image_filter_size / 2) >>
downscale_shift;
total_weight += weight;
fg += back_v * weight;
src_alpha += back_a * weight;
x_hr += base_type::m_rx_inv;
}
while(x_hr < filter_size);
}
y_hr += base_type::m_ry_inv;
++y_lr;
}
while(y_hr < filter_size);
fg /= total_weight;
src_alpha /= total_weight;
if(fg < 0) fg = 0;
if(src_alpha < 0) src_alpha = 0;
if(src_alpha > base_mask) src_alpha = base_mask;
if(fg > src_alpha) fg = src_alpha;
span->v = (value_type)fg;
span->a = (value_type)src_alpha;
++span;
++base_type::interpolator();
} while(--len);
return base_type::allocator().span();
}
};
//==============================================span_image_resample_gray
template<class ColorT,
class Interpolator,
class Allocator = span_allocator<ColorT> >
class span_image_resample_gray :
public span_image_resample<ColorT, Interpolator, Allocator>
{
public:
typedef ColorT color_type;
typedef Interpolator interpolator_type;
typedef Allocator alloc_type;
typedef span_image_resample<color_type, interpolator_type, alloc_type> base_type;
typedef typename color_type::value_type value_type;
typedef typename color_type::long_type long_type;
enum base_scale_e
{
base_shift = color_type::base_shift,
base_mask = color_type::base_mask,
downscale_shift = image_filter_shift
};
//--------------------------------------------------------------------
span_image_resample_gray(alloc_type& alloc) :
base_type(alloc)
{}
//--------------------------------------------------------------------
span_image_resample_gray(alloc_type& alloc,
const rendering_buffer& src,
const color_type& back_color,
interpolator_type& inter,
const image_filter_lut& filter) :
base_type(alloc, src, back_color, inter, filter)
{}
//--------------------------------------------------------------------
color_type* generate(int x, int y, unsigned len)
{
color_type* span = base_type::allocator().span();
base_type::interpolator().begin(x + base_type::filter_dx_dbl(),
y + base_type::filter_dy_dbl(), len);
long_type fg;
long_type src_alpha;
value_type back_v = base_type::background_color().v;
value_type back_a = base_type::background_color().a;
int diameter = base_type::filter().diameter();
int filter_size = diameter << image_subpixel_shift;
const int16* weight_array = base_type::filter().weight_array();
do
{
int rx;
int ry;
int rx_inv = image_subpixel_size;
int ry_inv = image_subpixel_size;
base_type::interpolator().coordinates(&x, &y);
base_type::interpolator().local_scale(&rx, &ry);
rx = (rx * base_type::m_blur_x) >> image_subpixel_shift;
ry = (ry * base_type::m_blur_y) >> image_subpixel_shift;
if(rx < image_subpixel_size)
{
rx = image_subpixel_size;
}
else
{
if(rx > image_subpixel_size * base_type::m_scale_limit)
{
rx = image_subpixel_size * base_type::m_scale_limit;
}
rx_inv = image_subpixel_size * image_subpixel_size / rx;
}
if(ry < image_subpixel_size)
{
ry = image_subpixel_size;
}
else
{
if(ry > image_subpixel_size * base_type::m_scale_limit)
{
ry = image_subpixel_size * base_type::m_scale_limit;
}
ry_inv = image_subpixel_size * image_subpixel_size / ry;
}
int radius_x = (diameter * rx) >> 1;
int radius_y = (diameter * ry) >> 1;
int maxx = base_type::source_image().width() - 1;
int maxy = base_type::source_image().height() - 1;
x += base_type::filter_dx_int() - radius_x;
y += base_type::filter_dy_int() - radius_y;
fg = src_alpha = image_filter_size / 2;
int y_lr = y >> image_subpixel_shift;
int y_hr = ((image_subpixel_mask - (y & image_subpixel_mask)) *
ry_inv) >>
image_subpixel_shift;
int total_weight = 0;
int x_lr_ini = x >> image_subpixel_shift;
int x_hr_ini = ((image_subpixel_mask - (x & image_subpixel_mask)) *
rx_inv) >>
image_subpixel_shift;
do
{
int weight_y = weight_array[y_hr];
int x_lr = x_lr_ini;
int x_hr = x_hr_ini;
if(y_lr >= 0 && y_lr <= maxy)
{
const value_type* fg_ptr = (const value_type*)
base_type::source_image().row(y_lr) + x_lr;
do
{
int weight = (weight_y * weight_array[x_hr] +
image_filter_size / 2) >>
downscale_shift;
if(x_lr >= 0 && x_lr <= maxx)
{
fg += *fg_ptr * weight;
src_alpha += base_mask * weight;
}
else
{
fg += back_v * weight;
src_alpha += back_a * weight;
}
total_weight += weight;
x_hr += rx_inv;
++fg_ptr;
++x_lr;
}
while(x_hr < filter_size);
}
else
{
do
{
int weight = (weight_y * weight_array[x_hr] +
image_filter_size / 2) >>
downscale_shift;
total_weight += weight;
fg += back_v * weight;
src_alpha += back_a * weight;
x_hr += rx_inv;
}
while(x_hr < filter_size);
}
y_hr += ry_inv;
++y_lr;
}
while(y_hr < filter_size);
fg /= total_weight;
src_alpha /= total_weight;
if(fg < 0) fg = 0;
if(src_alpha < 0) src_alpha = 0;
if(src_alpha > base_mask) src_alpha = base_mask;
if(fg > src_alpha) fg = src_alpha;
span->v = (value_type)fg;
span->a = (value_type)src_alpha;
++span;
++base_type::interpolator();
} while(--len);
return base_type::allocator().span();
}
};
}
#endif