mapnik/src/warp.cpp

195 lines
7.5 KiB
C++

/*****************************************************************************
*
* This file is part of Mapnik (c++ mapping toolkit)
*
* Copyright (C) 2011 Artem Pavlenko
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*
*****************************************************************************/
// mapnik
#include <mapnik/warp.hpp>
#include <mapnik/config.hpp>
#include <mapnik/image_data.hpp>
#include <mapnik/image_util.hpp>
#include <mapnik/box2d.hpp>
#include <mapnik/ctrans.hpp>
#include <mapnik/span_image_filter.hpp>
// agg
#include "agg_image_filters.h"
#include "agg_trans_bilinear.h"
#include "agg_span_interpolator_linear.h"
#include "agg_span_image_filter_rgba.h"
#include "agg_rendering_buffer.h"
#include "agg_pixfmt_rgba.h"
#include "agg_rasterizer_scanline_aa.h"
#include "agg_basics.h"
#include "agg_scanline_u.h"
#include "agg_renderer_scanline.h"
#include "agg_span_allocator.h"
#include "agg_image_accessors.h"
#include "agg_renderer_scanline.h"
namespace mapnik {
void reproject_and_scale_raster(raster & target, raster const& source,
proj_transform const& prj_trans,
double offset_x, double offset_y,
unsigned mesh_size,
double filter_radius,
scaling_method_e scaling_method)
{
CoordTransform ts(source.data_.width(), source.data_.height(),
source.ext_);
CoordTransform tt(target.data_.width(), target.data_.height(),
target.ext_, offset_x, offset_y);
unsigned i, j;
unsigned mesh_nx = ceil(source.data_.width()/double(mesh_size)+1);
unsigned mesh_ny = ceil(source.data_.height()/double(mesh_size)+1);
ImageData<double> xs(mesh_nx, mesh_ny);
ImageData<double> ys(mesh_nx, mesh_ny);
// Precalculate reprojected mesh
for(j=0; j<mesh_ny; j++) {
for (i=0; i<mesh_nx; i++) {
xs(i,j) = i*mesh_size;
ys(i,j) = j*mesh_size;
ts.backward(&xs(i,j), &ys(i,j));
}
}
prj_trans.backward(xs.getData(), ys.getData(), NULL, mesh_nx*mesh_ny);
// Initialize AGG objects
typedef agg::pixfmt_rgba32 pixfmt;
typedef pixfmt::color_type color_type;
typedef agg::renderer_base<pixfmt> renderer_base;
typedef agg::pixfmt_rgba32_pre pixfmt_pre;
typedef agg::renderer_base<pixfmt_pre> renderer_base_pre;
agg::rasterizer_scanline_aa<> rasterizer;
agg::scanline_u8 scanline;
agg::rendering_buffer buf((unsigned char*)target.data_.getData(),
target.data_.width(),
target.data_.height(),
target.data_.width()*4);
pixfmt_pre pixf_pre(buf);
renderer_base_pre rb_pre(pixf_pre);
rasterizer.clip_box(0, 0, target.data_.width(), target.data_.height());
agg::rendering_buffer buf_tile(
(unsigned char*)source.data_.getData(),
source.data_.width(),
source.data_.height(),
source.data_.width() * 4);
pixfmt pixf_tile(buf_tile);
typedef agg::image_accessor_clone<pixfmt> img_accessor_type;
img_accessor_type ia(pixf_tile);
agg::span_allocator<color_type> sa;
// Initialize filter
agg::image_filter_lut filter;
switch(scaling_method)
{
case SCALING_NEAR: break;
case SCALING_BILINEAR8: // TODO - impl this or remove?
case SCALING_BILINEAR:
filter.calculate(agg::image_filter_bilinear(), true); break;
case SCALING_BICUBIC:
filter.calculate(agg::image_filter_bicubic(), true); break;
case SCALING_SPLINE16:
filter.calculate(agg::image_filter_spline16(), true); break;
case SCALING_SPLINE36:
filter.calculate(agg::image_filter_spline36(), true); break;
case SCALING_HANNING:
filter.calculate(agg::image_filter_hanning(), true); break;
case SCALING_HAMMING:
filter.calculate(agg::image_filter_hamming(), true); break;
case SCALING_HERMITE:
filter.calculate(agg::image_filter_hermite(), true); break;
case SCALING_KAISER:
filter.calculate(agg::image_filter_kaiser(), true); break;
case SCALING_QUADRIC:
filter.calculate(agg::image_filter_quadric(), true); break;
case SCALING_CATROM:
filter.calculate(agg::image_filter_catrom(), true); break;
case SCALING_GAUSSIAN:
filter.calculate(agg::image_filter_gaussian(), true); break;
case SCALING_BESSEL:
filter.calculate(agg::image_filter_bessel(), true); break;
case SCALING_MITCHELL:
filter.calculate(agg::image_filter_mitchell(), true); break;
case SCALING_SINC:
filter.calculate(agg::image_filter_sinc(filter_radius), true); break;
case SCALING_LANCZOS:
filter.calculate(agg::image_filter_lanczos(filter_radius), true); break;
case SCALING_BLACKMAN:
filter.calculate(agg::image_filter_blackman(filter_radius), true); break;
}
// Project mesh cells into target interpolating raster inside each one
for(j=0; j<mesh_ny-1; j++) {
for (i=0; i<mesh_nx-1; i++) {
double polygon[8] = {xs(i,j), ys(i,j),
xs(i+1,j), ys(i+1,j),
xs(i+1,j+1), ys(i+1,j+1),
xs(i,j+1), ys(i,j+1)};
tt.forward(polygon+0, polygon+1);
tt.forward(polygon+2, polygon+3);
tt.forward(polygon+4, polygon+5);
tt.forward(polygon+6, polygon+7);
rasterizer.reset();
rasterizer.move_to_d(polygon[0]-1, polygon[1]-1);
rasterizer.line_to_d(polygon[2]+1, polygon[3]-1);
rasterizer.line_to_d(polygon[4]+1, polygon[5]+1);
rasterizer.line_to_d(polygon[6]-1, polygon[7]+1);
unsigned x0 = i * mesh_size;
unsigned y0 = j * mesh_size;
unsigned x1 = (i+1) * mesh_size;
unsigned y1 = (j+1) * mesh_size;
agg::trans_affine tr(polygon, x0, y0, x1, y1);
if (tr.is_valid())
{
typedef agg::span_interpolator_linear<agg::trans_affine>
interpolator_type;
interpolator_type interpolator(tr);
if (scaling_method == SCALING_NEAR) {
typedef agg::span_image_filter_rgba_nn
<img_accessor_type, interpolator_type>
span_gen_type;
span_gen_type sg(ia, interpolator);
agg::render_scanlines_aa(rasterizer, scanline, rb_pre,
sa, sg);
} else {
typedef mapnik::span_image_resample_rgba_affine
<img_accessor_type> span_gen_type;
span_gen_type sg(ia, interpolator, filter);
agg::render_scanlines_aa(rasterizer, scanline, rb_pre,
sa, sg);
}
}
}
}
}
}// namespace mapnik