/***************************************************************************** * * This file is part of Mapnik (c++ mapping toolkit) * * Copyright (C) 2021 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 #include #include #include #include MAPNIK_DISABLE_WARNING_PUSH #include #include #include MAPNIK_DISABLE_WARNING_POP #include MAPNIK_DISABLE_WARNING_PUSH #include #include "agg_image_accessors.h" #include "agg_pixfmt_rgba.h" #include "agg_pixfmt_gray.h" #include "agg_color_rgba.h" #include "agg_rasterizer_scanline_aa.h" #include "agg_renderer_scanline.h" #include "agg_rendering_buffer.h" #include "agg_scanline_u.h" #include "agg_span_allocator.h" #include "agg_span_image_filter_gray.h" #include "agg_span_image_filter_rgba.h" #include "agg_span_interpolator_linear.h" #include "agg_trans_affine.h" #include "agg_image_filters.h" MAPNIK_DISABLE_WARNING_POP namespace mapnik { using scaling_method_lookup_type = boost::bimap; static const scaling_method_lookup_type scaling_lookup = boost::assign::list_of (SCALING_NEAR,"near") (SCALING_BILINEAR,"bilinear") (SCALING_BICUBIC,"bicubic") (SCALING_SPLINE16,"spline16") (SCALING_SPLINE36,"spline36") (SCALING_HANNING,"hanning") (SCALING_HAMMING,"hamming") (SCALING_HERMITE,"hermite") (SCALING_KAISER,"kaiser") (SCALING_QUADRIC,"quadric") (SCALING_CATROM,"catrom") (SCALING_GAUSSIAN,"gaussian") (SCALING_BESSEL,"bessel") (SCALING_MITCHELL,"mitchell") (SCALING_SINC,"sinc") (SCALING_LANCZOS,"lanczos") (SCALING_BLACKMAN,"blackman") ; boost::optional scaling_method_from_string(std::string const& name) { boost::optional mode; scaling_method_lookup_type::right_const_iterator right_iter = scaling_lookup.right.find(name); if (right_iter != scaling_lookup.right.end()) { mode.reset(right_iter->second); } return mode; } boost::optional scaling_method_to_string(scaling_method_e scaling_method) { boost::optional mode; scaling_method_lookup_type::left_const_iterator left_iter = scaling_lookup.left.find(scaling_method); if (left_iter != scaling_lookup.left.end()) { mode.reset(left_iter->second); } return mode; } template void scale_image_agg(T & target, T const& source, scaling_method_e scaling_method, double image_ratio_x, double image_ratio_y, double x_off_f, double y_off_f, double filter_factor, boost::optional const& nodata_value) { // "the image filters should work namely in the premultiplied color space" // http://old.nabble.com/Re:--AGG--Basic-image-transformations-p1110665.html // "Yes, you need to use premultiplied images only. Only in this case the simple weighted averaging works correctly in the image fitering." // http://permalink.gmane.org/gmane.comp.graphics.agg/3443 using image_type = T; using pixel_type = typename image_type::pixel_type; using pixfmt_pre = typename detail::agg_scaling_traits::pixfmt_pre; using color_type = typename detail::agg_scaling_traits::color_type; using img_src_type = typename detail::agg_scaling_traits::img_src_type; using interpolator_type = typename detail::agg_scaling_traits::interpolator_type; using renderer_base_pre = agg::renderer_base; constexpr std::size_t pixel_size = sizeof(pixel_type); // define some stuff we'll use soon agg::rasterizer_scanline_aa<> ras; agg::scanline_u8 sl; agg::span_allocator sa; // initialize source AGG buffer agg::rendering_buffer rbuf_src(const_cast(source.bytes()), source.width(), source.height(), source.width() * pixel_size); pixfmt_pre pixf_src(rbuf_src); img_src_type img_src(pixf_src); // initialize destination AGG buffer (with transparency) agg::rendering_buffer rbuf_dst(target.bytes(), target.width(), target.height(), target.width() * pixel_size); pixfmt_pre pixf_dst(rbuf_dst); renderer_base_pre rb_dst_pre(pixf_dst); // create a scaling matrix agg::trans_affine img_mtx; img_mtx *= agg::trans_affine_translation(x_off_f, y_off_f); img_mtx /= agg::trans_affine_scaling(image_ratio_x, image_ratio_y); // create a linear interpolator for our scaling matrix interpolator_type interpolator(img_mtx); // draw an anticlockwise polygon to render our image into double scaled_width = target.width(); double scaled_height = target.height(); ras.reset(); ras.move_to_d(0.0, 0.0); ras.line_to_d(scaled_width, 0.0); ras.line_to_d(scaled_width, scaled_height); ras.line_to_d(0.0, scaled_height); if (scaling_method == SCALING_NEAR) { using span_gen_type = typename detail::agg_scaling_traits::span_image_filter; span_gen_type sg(img_src, interpolator); agg::render_scanlines_aa(ras, sl, rb_dst_pre, sa, sg); } else { using span_gen_type = typename detail::agg_scaling_traits::span_image_resample_affine; agg::image_filter_lut filter; detail::set_scaling_method(filter, scaling_method, filter_factor); boost::optional nodata; if (nodata_value) { nodata.emplace(safe_cast(*nodata_value)); } span_gen_type sg(img_src, interpolator, filter, nodata); agg::render_scanlines_aa(ras, sl, rb_dst_pre, sa, sg); } } template MAPNIK_DECL void scale_image_agg(image_rgba8 &, image_rgba8 const&, scaling_method_e, double, double , double, double , double, boost::optional const &); template MAPNIK_DECL void scale_image_agg(image_gray8 &, image_gray8 const&, scaling_method_e, double, double , double, double , double, boost::optional const &); template MAPNIK_DECL void scale_image_agg(image_gray8s &, image_gray8s const&, scaling_method_e, double, double , double, double , double, boost::optional const &); template MAPNIK_DECL void scale_image_agg(image_gray16 &, image_gray16 const&, scaling_method_e, double, double , double, double , double, boost::optional const &); template MAPNIK_DECL void scale_image_agg(image_gray16s &, image_gray16s const&, scaling_method_e, double, double , double, double , double, boost::optional const &); template MAPNIK_DECL void scale_image_agg(image_gray32 &, image_gray32 const&, scaling_method_e, double, double , double, double , double, boost::optional const &); template MAPNIK_DECL void scale_image_agg(image_gray32s &, image_gray32s const&, scaling_method_e, double, double , double, double , double, boost::optional const &); template MAPNIK_DECL void scale_image_agg(image_gray32f &, image_gray32f const&, scaling_method_e, double, double , double, double , double, boost::optional const &); template MAPNIK_DECL void scale_image_agg(image_gray64 &, image_gray64 const&, scaling_method_e, double, double , double, double , double, boost::optional const &); template MAPNIK_DECL void scale_image_agg(image_gray64s &, image_gray64s const&, scaling_method_e, double, double , double, double , double, boost::optional const &); template MAPNIK_DECL void scale_image_agg(image_gray64f &, image_gray64f const&, scaling_method_e, double, double , double, double , double, boost::optional const &); }