poly_subpixel_shift
poly_subpixel_scale = 1<<poly_subpixel_shift, //----poly_subpixel_scale
int ex1 = x1 >> poly_subpixel_shift;
int ex2 = x2 >> poly_subpixel_shift;
enum dx_limit_e { dx_limit = 16384 << poly_subpixel_shift };
int ex1 = x1 >> poly_subpixel_shift;
int ex2 = x2 >> poly_subpixel_shift;
int ey1 = y1 >> poly_subpixel_shift;
int ey2 = y2 >> poly_subpixel_shift;
int ex = x1 >> poly_subpixel_shift;
int two_fx = (x1 - (ex << poly_subpixel_shift)) << 1;
set_curr_cell(x_from >> poly_subpixel_shift, ey1);
set_curr_cell(x_from >> poly_subpixel_shift, ey1);
int cover = area >> (poly_subpixel_shift*2 + 1 - aa_shift);
alpha = calculate_alpha((cover << (poly_subpixel_shift + 1)) - area,
alpha = calculate_alpha(cover << (poly_subpixel_shift + 1),
int cover = area >> (poly_subpixel_shift*2 + 1 - aa_shift);
alpha = calculate_alpha((cover << (poly_subpixel_shift + 1)) - area);
alpha = calculate_alpha(cover << (poly_subpixel_shift + 1));
int cover = area >> (poly_subpixel_shift*2 + 1 - aa_shift);
<< (poly_subpixel_shift + 1)) - area1) : 0;
<< (poly_subpixel_shift + 1)) - area2) : 0;
<< (poly_subpixel_shift + 1)) - area3) : 0;
<< (poly_subpixel_shift + 1));
<< (poly_subpixel_shift + 1));
<< (poly_subpixel_shift + 1));
<< (poly_subpixel_shift + 1));
<< (poly_subpixel_shift + 1));
<< (poly_subpixel_shift + 1));