color_map_writer.h

#pragma once
 
#include <string>
 
#include <cgv/media/image/image_writer.h>
#include <cgv/render/color_map.h>
#include <cgv/utils/file.h>
 
#include <tinyxml2/tinyxml2.h>
 
namespace cgv {
namespace app {
 
class color_map_writer {
private:
    static void write_color_map(tinyxml2::XMLPrinter& printer, const std::string& name, const cgv::render::color_map& color_map) {
 
        printer.OpenElement("ColorMap");
        printer.PushAttribute("name", name.c_str());
 
        for(const auto& color_point : color_map.ref_color_points()) {
            printer.OpenElement("ColorPoint");
            printer.PushAttribute("x", color_point.first);
            printer.PushAttribute("r", color_point.second.R());
            printer.PushAttribute("g", color_point.second.G());
            printer.PushAttribute("b", color_point.second.B());
            printer.CloseElement();
        }
 
        for(const auto& opacity_point : color_map.ref_opacity_points()) {
            printer.OpenElement("OpacityPoint");
            printer.PushAttribute("x", opacity_point.first);
            printer.PushAttribute("o", opacity_point.second);
            printer.CloseElement();
        }
        
        printer.CloseElement();
    }
 
public:
    static void to_xml_printer(tinyxml2::XMLPrinter& printer, const std::string& name, const cgv::render::color_map& color_map, bool put_parent_tag = true) {
 
        std::vector<std::string> names = {name};
        std::vector<cgv::render::color_map> color_maps = {color_map};
        to_xml_printer(printer, names, color_maps, put_parent_tag);
    }
 
    static void to_xml_printer(tinyxml2::XMLPrinter& printer, const std::vector<std::string>& names, const std::vector<cgv::render::color_map>& color_maps, bool put_parent_tag = true) {
 
        if (put_parent_tag)
            printer.OpenElement("ColorMaps");
 
        if (names.size() == color_maps.size()) {
            for (size_t i = 0; i < names.size(); ++i)
                write_color_map(printer, names[i], color_maps[i]);
        }
 
        if (put_parent_tag)
            printer.CloseElement();
    }
 
    static std::string to_xml(const std::string& name, const cgv::render::color_map& color_map, bool put_parent_tag = true) {
        
        std::vector<std::string> names = { name };
        std::vector<cgv::render::color_map> color_maps = { color_map };
 
        return to_xml(names, color_maps, put_parent_tag);
    }
 
    static std::string to_xml(const std::vector<std::string>& names, const std::vector<cgv::render::color_map>& color_maps, bool put_parent_tag = true) {
        
        tinyxml2::XMLPrinter printer;
        to_xml_printer(printer, names, color_maps, put_parent_tag);
        std::string xml = printer.CStr();
 
        return xml;
    }
 
    static bool write_to_xml_file(const std::string& file_name, const std::string& name, const cgv::render::color_map& color_map, bool put_parent_tag = true) {
    
        std::vector<std::string> names = { name };
        std::vector<cgv::render::color_map> color_maps = { color_map };
 
        return write_to_xml_file(file_name, names, color_maps, put_parent_tag);
    }
 
    static bool write_to_xml_file(const std::string& file_name, const std::vector<std::string>& names, const std::vector<cgv::render::color_map>& color_maps, bool put_parent_tag = true) {
 
        return cgv::utils::file::write(file_name, to_xml(names, color_maps, put_parent_tag), true);
    }
 
    static bool write_to_png_file(const std::string& file_name, const cgv::render::color_map& color_map, size_t resolution) {
    
        std::vector<rgba> data = color_map.interpolate(static_cast<size_t>(resolution));
 
        bool has_opacity = !color_map.ref_opacity_points().empty();
 
        std::vector<uint8_t> data_8(4 * data.size());
        for(unsigned i = 0; i < data.size(); ++i) {
            rgba col = data[i];
            data_8[4 * i + 0] = static_cast<uint8_t>(255.0f * col.R());
            data_8[4 * i + 1] = static_cast<uint8_t>(255.0f * col.G());
            data_8[4 * i + 2] = static_cast<uint8_t>(255.0f * col.B());
            data_8[4 * i + 3] = has_opacity ? static_cast<uint8_t>(255.0f * col.alpha()) : 255;
        }
 
        cgv::data::data_view dv = cgv::data::data_view(new cgv::data::data_format((unsigned)resolution, 1, cgv::type::info::TI_UINT8, cgv::data::CF_RGBA), data_8.data());
 
        cgv::media::image::image_writer writer(file_name);
 
        return writer.write_image(dv);
    }
};
 
}
}