petalc/genlogo.d

module genlogo;

import std.experimental.all;

void main()
{
    foreach (i; 1..20)
    {
        draw(i);
    }
}

void draw(int numPetals)
{
    enum pi = 3.1415927;
    auto dim = 256;
    auto center = 196;
    auto o = File("petal%s.svg".format(numPetals), "w");
    o.writefln(`<svg width="%s" height="%s">
  <defs>
    <radialGradient id="pinky">
      <stop stop-color="#b3879d" offset="0%%"/>
      <stop stop-color="#d8a4be" offset="50%%"/>
      <stop stop-color="#e2bace" offset="90%%"/>
    </radialGradient>
  </defs>
  <polygon stroke="#3c2631" fill="url(#pinky)" points="%s,%s`, center * 2,  center * 2, center, center);
    // We have five petals. Their points are balanced at the five directions: top, top-right,
    // low-right, low-left, top-left.
    auto radius = (dim / 2) - (dim / 30);
    // 90% of the circle is divided between the petals, and there are five petals.
    auto innerRadius = dim / 9;
    auto midRadius = dim * 0.75;
    auto petalCoverage = 0.95;
    auto margin = (1 - petalCoverage) / numPetals * 2 * pi;
    auto perPetal = petalCoverage / numPetals;
    auto petalWidth = 2 * pi / numPetals;

    void writePoint(double radians, double radius)
    {
        auto x = sin(radians) * radius;
        auto y = cos(radians) * radius;
        o.writefln(" %s,%s", x + center, y + center);
    }
    foreach (i; 0 .. numPetals)
    {
        auto d1 = petalWidth * i + margin;
        writefln("%s: %s", i, d1);
        auto d2 = d1 + petalWidth - 2 * margin;
        auto d3 = d1 + (d2 - d1) / 2;
        writePoint(d3, innerRadius);
        writePoint(d1, radius);
        writePoint(d3, midRadius);
        writePoint(d2, radius);
        writePoint(d3, innerRadius);
    }
    o.writefln(` %1$s,%1$s" />
  <circle fill="#ac7ba8" stroke="#3c2631" cx="%1$s" cy="%1$s" r="%2$s" />`, center, dim / 6);
    o.writefln(`<circle fill="#665683" cx="%s" cy="%s" r="%s" />
</svg>`, center, center, dim / 10);
    o.flush;
    o.close;
}