paths.cpp - master - SilovAndrey/easel_examples

paths.cpp
95 строк3 KB
Andrey HomePC
Add easel_examples v0.1.0 with shapes, space, paths examples
10 июл 2026, 10:34
10 июл 2026, 10:348ecc405
module;
#include <utility>

module App;

using namespace easel;

constexpr auto window_size = extent{640, 420};

const Path p1{"M 100 100 L 300 100 L 200 300 z"};
const Path p2{"M100,200 C100,100 250,100 250,200 S400,300 400,200"};
const Path p3{"M200,300 Q400,50 600,300 T1000,300"};
const Path p4{"M200,300 L400,50 L600,300 L800,550 L1000,300"};
const Path p5{"M300,200 h-150 a150,150 0 1,0 150,-150 z"};
const Path p6{"M275,175 v-150 a150,150 0 0,0 -150,150 z"};
const Path p7{
    "M600,350 l 50,-25"
    "a25,25 -30 0,1 50,-25 l 50,-25"
    "a25,50 -30 0,1 50,-25 l 50,-25"
    "a25,75 -30 0,1 50,-25 l 50,-25"
    "a25,100 -30 0,1 50,-25 l 50,-25"
};
Path dot;

void draw(canvas& cnv, int w, int h)
{
   auto stroke_fill =
      [&](const Path& p, color fill_c, color stroke_c)
      {
         //auto pp = cnv.add_path(std::move(p));
         cnv.fill_style(fill_c);
         cnv.stroke_style(stroke_c);
         cnv.fill(p);
         cnv.line_width(5);
         cnv.stroke(p);
      };

   auto stroke =
      [&](Path const& p, color stroke_c)
      {
         //cnv.add_path(p);
         cnv.stroke_style(stroke_c);
         cnv.line_width(5);
         cnv.stroke(p);
      };


   // These paths are defined using SVG-style strings lifted off the
   // W3C SVG documentation: https://www.w3.org/TR/SVG/paths.html

   {
      auto save = cnv.new_state();
      //cnv.scale(w / window_size.x * 0.5, window_size.y / h * 0.5);
      cnv.scale(0.5, 0.5);

      cnv.translate(-40, 0);
      stroke_fill(p1, colors::green.opacity(0.5), colors::ivory);

      cnv.translate(220, 0);
      stroke(p2, colors::light_sky_blue);

      cnv.translate(-150, 250);
      stroke(p3, colors::light_sky_blue);

      stroke(p4, colors::light_gray.opacity(0.5));
      cnv.fill_style(colors::white.opacity(0.5));
      cnv.fill(dot);
      cnv.translate(150, -250);

      cnv.translate(350, 0);
      stroke_fill(p5, colors::red.opacity(0.8), colors::ivory);

      stroke_fill(p6, colors::blue.opacity(0.8), colors::ivory);

      cnv.translate(-350, 200);
      stroke(p7, colors::ivory);
   }

   // cnv.font(font_descr{"Open Sans", 12}.thin());
   // cnv.fill_color(colors::antique_white);
   // cnv.text_align(cnv.bottom);
   // auto url = "https://www.w3.org/TR/SVG/paths.html";
   // cnv.fill_text(url, {5, window_size.y-5});
}

int start(int argc, char const* argv[])
{
  dot.add_circle(200, 300, 10);
  dot.add_circle(600, 300, 10);
  dot.add_circle(1000, 300, 10);
  dot.add_circle(400, 50, 10);
  dot.add_circle(800, 550, 10);

   return run_app(argc, argv, window_size, colors::gray[10]);
}