#include "triangle.h"
#include "gpl_assert.h"

#ifdef __APPLE__
#include <OpenGL/gl.h>
#include <OpenGL/glu.h>
#else
#include <GL/gl.h>
#include <GL/glu.h>
#endif

Triangle::Triangle(): Game_object(/* red = */ 0.0,
                                        /* green = */ 1.0,
                                        /* blue = */ 0.0
                                 )
{
        m_size = 10;
        m_rotation = 0;
        m_skew = 1.0;
        register_member_variable("size", &m_size);
        register_member_variable("rotation", &m_rotation);
        register_member_variable("skew", &m_skew);
        m_object_type_name = "Triangle"; 

        // 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);
}

void 
Triangle::updated(string name)
{
    m_display_list_dirty = true;
}

/* virtual */ void 
Triangle::build_display_list()
{
    assert(m_display_list);

    double midpoint_x = m_x + m_size/2.0;
    double top_point_y = 1.118 * m_size * m_skew + m_y;

    // assume size or skew changed:  recalculate the height and width
    m_w = m_size;
    m_h = (int) top_point_y - m_y;

    glNewList(m_display_list, GL_COMPILE);
    glMatrixMode(GL_MODELVIEW);
    glPushMatrix();
    if (m_rotation != 0)
    {
        double center_x = midpoint_x;
        double center_y = m_y + ((top_point_y - m_y) * .5);
        glTranslated(center_x, center_y, 0);
        glRotated(m_rotation, 0, 0, 1);
        glTranslated(-center_x, -center_y, 0);
    }
    glColor3f(m_red, m_green, m_blue);
    glBegin(GL_TRIANGLES);
        glVertex2i(m_x, m_y);
        glVertex2i(m_x + m_size, m_y);
        glVertex2i((int) midpoint_x, (int) top_point_y);
    glEnd();
    glPopMatrix();
    glEndList();
}