load("zegraph.dll");

PI2 = 6.28318530717959;
    
class Shape2D {
    
    function plus(size=5)
    {
        line = zegraph("line");
        vert = zegraph("vertex");
        line.type("lines");
        line.vertex(vert);
        d = size / 2.0;
        vert.add(-d, 0, 0,  d, 0, 0,  0, -d, 0,  0, d, 0);
        return line;
    }
    
    function cross(size=5)
    {
        line = zegraph("line");
        vert = zegraph("vertex");
        line.type("lines");
        line.smooth(true);
        line.vertex(vert);
        d = size / 2.0;
        vert.add(-d, -d, 0,  d, d, 0,  -d, d, 0, d, -d, 0);
        return line;
    }
    
    function triangle(size=5)
    {
        poly = zegraph("polygon");
        vert = zegraph("vertex");
        poly.type("triangles");
        poly.smooth(true);
        poly.vertex(vert);
        dx = size / 2.0;
        dy = sqrt(size*size + dx*dx) / 2.0;
        vert.add(0, dy, 0,  -dx, -dy, 0,  dx, -dy, 0);
        return poly;
    }
    
    function square(size=5)
    {
        poly = zegraph("polygon");
        vert = zegraph("vertex");
        poly.type("quads");
        poly.vertex(vert);
        d = size / 2.0;
        vert.add(-d, -d, 0, d, -d, 0, d, d, 0, -d, d, 0);
        return poly;
    }
    
    function diamond(size=5)
    {
        poly = zegraph("polygon");
        vert = zegraph("vertex");
        poly.type("quads");
        poly.smooth(true);
        poly.vertex(vert);
        d = size / 2.0;
        vert.add(-d, 0, 0,  0, -d, 0,  d, 0, 0,  0, d, 0);
        return poly;
    }
    
    function circle(size=5)
    {
        r = size / 2.0;
        d = PI2 / 32;
        vert = zegraph("vertex");
        line = zegraph("line");
        line.type("loop");
        line.smooth(true);
        line.vertex(vert);
        for (a = 0.0; a < PI2; a += d) {
            x = r*cos(a);
            y = r*sin(a);
            vert.add(x, y, 0);
        }
        return line;
    }
    
    function pie(size=5)
    {
        r = size / 2.0;
        d = PI2 / 32;
        vert = zegraph("vertex");
        poly = zegraph("polygon");
        poly.type("trianglefan");
        poly.smooth(true);
        poly.vertex(vert);
        for (a = 0.0; a <= PI2; a += d) {
            x = r*cos(a);
            y = r*sin(a);
            vert.add(x, y, 0);
        }
        return poly;
    }
}