static void
_cairo_polygon_add_edge (cairo_polygon_t *polygon,
const cairo_point_t *p1,
const cairo_point_t *p2)
{
cairo_edge_t *edge;
/* drop horizontal edges */
if (p1->y == p2->y)
goto DONE;
if (polygon->num_edges == polygon->edges_size) {
if (! _cairo_polygon_grow (polygon))
return;
}
edge = &polygon->edges[polygon->num_edges++];
if (p1->y < p2->y) {
edge->edge.p1 = *p1;
edge->edge.p2 = *p2;
edge->clockWise = 1;
} else {
edge->edge.p1 = *p2;
edge->edge.p2 = *p1;
edge->clockWise = 0;
}
DONE:
_cairo_polygon_move_to (polygon, p2);
}
void
_cairo_polygon_line_to (cairo_polygon_t *polygon,
const cairo_point_t *point)
{
if (polygon->has_current_point)
_cairo_polygon_add_edge (polygon, &polygon->current_point, point);
else
_cairo_polygon_move_to (polygon, point);
}
static cairo_status_t
_cairo_filler_move_to (void *closure,
const cairo_point_t *point)
{
cairo_filler_t *filler = closure;
cairo_polygon_t *polygon = filler->polygon;
_cairo_polygon_close (polygon);
return _cairo_polygon_move_to (polygon, point);
}
static cairo_status_t
_cairo_filler_move_to (void *closure, cairo_point_t *point)
{
cairo_filler_t *filler = closure;
cairo_polygon_t *polygon = &filler->polygon;
_cairo_polygon_close (polygon);
_cairo_polygon_move_to (polygon, point);
filler->current_point = *point;
return _cairo_polygon_status (&filler->polygon);
}
static cairo_status_t
_cairo_filler_move_to (void *closure, cairo_point_t *point)
{
cairo_status_t status;
cairo_filler_t *filler = closure;
cairo_polygon_t *polygon = &filler->polygon;
status = _cairo_polygon_close (polygon);
if (status)
return status;
status = _cairo_polygon_move_to (polygon, point);
if (status)
return status;
filler->current_point = *point;
return CAIRO_STATUS_SUCCESS;
}
static cairo_status_t
_cairo_stroker_add_cap (cairo_stroker_t *stroker, cairo_stroke_face_t *f)
{
cairo_status_t status;
if (stroker->style->line_cap == CAIRO_LINE_CAP_BUTT)
return CAIRO_STATUS_SUCCESS;
switch (stroker->style->line_cap) {
case CAIRO_LINE_CAP_ROUND: {
int i;
int start, stop;
cairo_slope_t slope;
cairo_point_t tri[3];
cairo_pen_t *pen = &stroker->pen;
slope = f->dev_vector;
start = _cairo_pen_find_active_cw_vertex_index (pen, &slope);
slope.dx = -slope.dx;
slope.dy = -slope.dy;
stop = _cairo_pen_find_active_cw_vertex_index (pen, &slope);
tri[0] = f->point;
tri[1] = f->cw;
for (i=start; i != stop; i = (i+1) % pen->num_vertices) {
tri[2] = f->point;
_translate_point (&tri[2], &pen->vertices[i].point);
status = _cairo_traps_tessellate_triangle (stroker->traps, tri);
if (unlikely (status))
return status;
tri[1] = tri[2];
}
tri[2] = f->ccw;
return _cairo_traps_tessellate_triangle (stroker->traps, tri);
}
case CAIRO_LINE_CAP_SQUARE: {
double dx, dy;
cairo_slope_t fvector;
cairo_point_t occw, ocw;
cairo_polygon_t polygon;
dx = f->usr_vector.x;
dy = f->usr_vector.y;
dx *= stroker->style->line_width / 2.0;
dy *= stroker->style->line_width / 2.0;
cairo_matrix_transform_distance (stroker->ctm, &dx, &dy);
fvector.dx = _cairo_fixed_from_double (dx);
fvector.dy = _cairo_fixed_from_double (dy);
occw.x = f->ccw.x + fvector.dx;
occw.y = f->ccw.y + fvector.dy;
ocw.x = f->cw.x + fvector.dx;
ocw.y = f->cw.y + fvector.dy;
_cairo_polygon_init (&polygon);
_cairo_polygon_move_to (&polygon, &f->cw);
_cairo_polygon_line_to (&polygon, &ocw);
_cairo_polygon_line_to (&polygon, &occw);
_cairo_polygon_line_to (&polygon, &f->ccw);
_cairo_polygon_close (&polygon);
status = _cairo_polygon_status (&polygon);
if (status == CAIRO_STATUS_SUCCESS) {
status = _cairo_bentley_ottmann_tessellate_polygon (stroker->traps,
&polygon,
CAIRO_FILL_RULE_WINDING);
}
_cairo_polygon_fini (&polygon);
return status;
}
case CAIRO_LINE_CAP_BUTT:
default:
return CAIRO_STATUS_SUCCESS;
}
}