cairo_int_status_t
_cairo_path_fixed_stroke_rectilinear_to_boxes (const cairo_path_fixed_t *path,
const cairo_stroke_style_t *stroke_style,
const cairo_matrix_t *ctm,
cairo_antialias_t antialias,
cairo_boxes_t *boxes)
{
cairo_rectilinear_stroker_t rectilinear_stroker;
cairo_int_status_t status;
cairo_box_t box;
assert (_cairo_path_fixed_stroke_is_rectilinear (path));
if (! _cairo_rectilinear_stroker_init (&rectilinear_stroker,
stroke_style, ctm, antialias,
boxes))
{
return CAIRO_INT_STATUS_UNSUPPORTED;
}
if (! rectilinear_stroker.dash.dashed &&
_cairo_path_fixed_is_stroke_box (path, &box) &&
/* if the segments overlap we need to feed them into the tessellator */
box.p2.x - box.p1.x > 2* rectilinear_stroker.half_line_x &&
box.p2.y - box.p1.y > 2* rectilinear_stroker.half_line_y)
{
cairo_box_t b;
/* top */
b.p1.x = box.p1.x - rectilinear_stroker.half_line_x;
b.p2.x = box.p2.x + rectilinear_stroker.half_line_x;
b.p1.y = box.p1.y - rectilinear_stroker.half_line_y;
b.p2.y = box.p1.y + rectilinear_stroker.half_line_y;
status = (cairo_int_status_t)_cairo_boxes_add (boxes, antialias, &b);
assert (status == CAIRO_INT_STATUS_SUCCESS);
/* left (excluding top/bottom) */
b.p1.x = box.p1.x - rectilinear_stroker.half_line_x;
b.p2.x = box.p1.x + rectilinear_stroker.half_line_x;
b.p1.y = box.p1.y + rectilinear_stroker.half_line_y;
b.p2.y = box.p2.y - rectilinear_stroker.half_line_y;
status = (cairo_int_status_t)_cairo_boxes_add (boxes, antialias, &b);
assert (status == CAIRO_INT_STATUS_SUCCESS);
/* right (excluding top/bottom) */
b.p1.x = box.p2.x - rectilinear_stroker.half_line_x;
b.p2.x = box.p2.x + rectilinear_stroker.half_line_x;
b.p1.y = box.p1.y + rectilinear_stroker.half_line_y;
b.p2.y = box.p2.y - rectilinear_stroker.half_line_y;
status = (cairo_int_status_t)_cairo_boxes_add (boxes, antialias, &b);
assert (status == CAIRO_INT_STATUS_SUCCESS);
/* bottom */
b.p1.x = box.p1.x - rectilinear_stroker.half_line_x;
b.p2.x = box.p2.x + rectilinear_stroker.half_line_x;
b.p1.y = box.p2.y - rectilinear_stroker.half_line_y;
b.p2.y = box.p2.y + rectilinear_stroker.half_line_y;
status = (cairo_int_status_t)_cairo_boxes_add (boxes, antialias, &b);
assert (status == CAIRO_INT_STATUS_SUCCESS);
goto done;
}
if (boxes->num_limits) {
_cairo_rectilinear_stroker_limit (&rectilinear_stroker,
boxes->limits,
boxes->num_limits);
}
status = (cairo_int_status_t)_cairo_path_fixed_interpret (path,
_cairo_rectilinear_stroker_move_to,
rectilinear_stroker.dash.dashed ?
_cairo_rectilinear_stroker_line_to_dashed :
_cairo_rectilinear_stroker_line_to,
NULL,
_cairo_rectilinear_stroker_close_path,
&rectilinear_stroker);
if (unlikely (status))
goto BAIL;
if (rectilinear_stroker.dash.dashed)
status = (cairo_int_status_t)_cairo_rectilinear_stroker_emit_segments_dashed (&rectilinear_stroker);
else
status = (cairo_int_status_t)_cairo_rectilinear_stroker_emit_segments (&rectilinear_stroker);
if (unlikely (status))
goto BAIL;
/* As we incrementally tessellate, we do not eliminate self-intersections */
status = (cairo_int_status_t)_cairo_bentley_ottmann_tessellate_boxes (boxes,
CAIRO_FILL_RULE_WINDING,
boxes);
if (unlikely (status))
goto BAIL;
done:
_cairo_rectilinear_stroker_fini (&rectilinear_stroker);
return (cairo_int_status_t)CAIRO_STATUS_SUCCESS;
BAIL:
_cairo_rectilinear_stroker_fini (&rectilinear_stroker);
_cairo_boxes_clear (boxes);
return status;
}
static cairo_int_status_t
_cairo_path_fixed_stroke_rectilinear (cairo_path_fixed_t *path,
cairo_stroke_style_t *stroke_style,
const cairo_matrix_t *ctm,
cairo_traps_t *traps)
{
cairo_rectilinear_stroker_t rectilinear_stroker;
cairo_int_status_t status;
/* This special-case rectilinear stroker only supports
* miter-joined lines (not curves) and a translation-only matrix
* (though it could probably be extended to support a matrix with
* uniform, integer scaling).
*
* It also only supports horizontal and vertical line_to
* elements. But we don't catch that here, but instead return
* UNSUPPORTED from _cairo_rectilinear_stroker_line_to if any
* non-rectilinear line_to is encountered.
*/
if (path->has_curve_to)
return CAIRO_INT_STATUS_UNSUPPORTED;
if (stroke_style->line_join != CAIRO_LINE_JOIN_MITER)
return CAIRO_INT_STATUS_UNSUPPORTED;
/* If the miter limit turns right angles into bevels, then we
* can't use this optimization. Remember, the ratio is
* 1/sin(ɸ/2). So the cutoff is 1/sin(π/4.0) or ⎷2,
* which we round for safety. */
if (stroke_style->miter_limit < M_SQRT2)
return CAIRO_INT_STATUS_UNSUPPORTED;
if (! (stroke_style->line_cap == CAIRO_LINE_CAP_BUTT ||
stroke_style->line_cap == CAIRO_LINE_CAP_SQUARE))
{
return CAIRO_INT_STATUS_UNSUPPORTED;
}
if (! (_cairo_matrix_is_identity (ctm) ||
_cairo_matrix_is_translation (ctm)))
{
return CAIRO_INT_STATUS_UNSUPPORTED;
}
_cairo_rectilinear_stroker_init (&rectilinear_stroker,
stroke_style,
ctm,
traps);
if (traps->has_limits) {
_cairo_rectilinear_stroker_limit (&rectilinear_stroker,
&traps->limits);
}
status = _cairo_path_fixed_interpret (path,
CAIRO_DIRECTION_FORWARD,
_cairo_rectilinear_stroker_move_to,
rectilinear_stroker.dash.dashed ?
_cairo_rectilinear_stroker_line_to_dashed :
_cairo_rectilinear_stroker_line_to,
NULL,
_cairo_rectilinear_stroker_close_path,
&rectilinear_stroker);
if (unlikely (status))
goto BAIL;
if (rectilinear_stroker.dash.dashed)
status = _cairo_rectilinear_stroker_emit_segments_dashed (&rectilinear_stroker);
else
status = _cairo_rectilinear_stroker_emit_segments (&rectilinear_stroker);
BAIL:
_cairo_rectilinear_stroker_fini (&rectilinear_stroker);
if (unlikely (status))
_cairo_traps_clear (traps);
return status;
}