// Drawable star ---------------------------------------------------------------

#include "drawable_star.h"

#include <cmath>
#include <iostream>

using namespace std;

// Static class members --------------------------------------------------------

int Star::DisplayListId = -1;

// Constructor -----------------------------------------------------------------

Star::Star(const double pX, const double pY, const double pZ)
    : Drawable(pX, pY, pZ)
{
    if (DisplayListId < 0) {
    	DisplayListId = glGenLists(1);
	glNewList(DisplayListId, GL_COMPILE); {
	    render();
	} glEndList();
    }
}

// Draw ------------------------------------------------------------------------

void 
Star::draw()
{
    glPushMatrix();
    glColor3fv(color);
    glTranslatef(x, y, z);
    glCallList(DisplayListId);
    glPopMatrix();
}

// Render ----------------------------------------------------------------------

void
Star::render()
{
    glBegin(GL_TRIANGLE_FAN); {
	double ox = 0.0, oy = 0.0, radius = 10.0;
	int triangles = 32;

	glVertex2f(ox, oy);
	for (int i = 0; i <= triangles; i++) {
	    double angle = i * 2.0 * M_PI / triangles;
	    if (i % 2)
		radius *= 4;
	    else
		radius /= 4;
	    glVertex2f(ox + radius * cos(angle), oy + radius * sin(angle));
	}
    } glEnd();
}

// vim: set sts=4 sw=4 ts=8 ft=cpp: --------------------------------------------