Objective: We now need to populate ellipse to achieve the depiction of Taiji.

MFC depicts Taiji figure can use Pie for round filling, but how AGG can depict the semicircle, and then fill the semicircle, currently found Agg::ellipse can not be this big.

inline unsigned Ellipse::vertex (double* x, double* y)

{

if (M_step = = M_num)

{

++m_step;

return Path_cmd_end_poly | Path_flags_close | PATH_FLAGS_CCW;

}

if (M_step > M_num) return path_cmd_stop;

Double angle = double (m_step)/double (m_num) * 2.0 * PI;

if (M_CW) angle = 2.0 * Pi-angle;

*x = m_x + cos (angle) * M_RX;

*y = m_y + sin (angle) * M_RY;

m_step++;

Return ((M_step = = 1)? path_cmd_move_to:path_cmd_line_to);

}

currently even by modifying agg::ellipse 's function code as above:

To modify a row:

Double angle =double (m_step)/double (m_num) * 1.0 * PI;

Depict half the angle, just show semicircle!!

It is then able to depict a semicircle and fill, but here is a problem where the semicircular position needs to be adjusted and slightly rotated according to the center of the circle. Here's the problem:

The previous section has explained that the rotation of the rotate function for the Agg::trans_affine class is completely uncontrollable and does not know where to go!!!

Objective: We now need to populate ellipse to achieve the depiction of Taiji.