#include "circle.h"
#include "gpl_assert.h"

Circle::Circle() :  Game_object(/* red = */ 0.0,
                                /* green = */ 0.0,
                                /* blue = */ 1.0
                               )
{
        m_radius = 10;
        register_member_variable("radius", &m_radius);
        m_object_type_name = "Circle";

        // the width and height are derived from the radius
        m_w = 2*m_radius;
        m_h = 2*m_radius;

        // width and height are derived --> user cannot change them
        Status status;
        status = mark_member_variable_as_derived("w");
        assert(status == OK);
        status = mark_member_variable_as_derived("h");
        assert(status == OK);

        m_quadric = 0;
}

void 
Circle::updated(string name)
{
    if (name == "radius")
    {
        m_w = 2*m_radius;
        m_h = 2*m_radius;
    }
    m_display_list_dirty = true;
}

void
Circle::build_display_list()
{
    assert(m_display_list);
    if (m_quadric == 0)
    {
        m_quadric = gluNewQuadric();
        gluQuadricDrawStyle(m_quadric, GLU_FILL);
    }
    glNewList(m_display_list, GL_COMPILE);
    glMatrixMode(GL_MODELVIEW);
    glPushMatrix();
    glTranslated(m_x + m_radius, m_y + m_radius, 0);
    glColor3f(m_red, m_green, m_blue);
    gluDisk(m_quadric, 
            /* innerRadius = */ 0,    // creates a hole in center
            /* outerRadius = */ m_radius,
            /* slices = */ 20,
            /* rings = */ 1
           );
    glPopMatrix();
    glEndList();

    // width and height are derived from the radius
    m_w = 2*m_radius;
    m_h = 2*m_radius;
}