Lerking/gtk
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

Implement gsk_path_measure_in_fill

Browse Source 
Implement this in the obvious way, using the decomposed form
of standard contours. Since the decomposed form is part of the
measure object, this api moves from gsk_path_in_fill to
gsk_path_measure_in_fill.
This commit is contained in:
Matthias Clasen
2020-11-26 23:15:47 -05:00
parent 798234a776
commit c65b978ac6
4 changed files with 204 additions and 4 deletions
Download Patch File Download Diff File Expand all files Collapse all files

156
gsk/gskpath.c
View File

@@ -87,6 +87,10 @@ struct _GskContourClass
gpointer measure_data,
float start,
float end);
int (* get_winding) (const GskContour *contour,
gpointer measure_data,
const graphene_point_t *point,
gboolean *on_edge);
};
struct _GskPath
@@ -481,6 +485,23 @@ gsk_rect_contour_add_segment (const GskContour *contour,
}
}
static int
gsk_rect_contour_get_winding (const GskContour *contour,
gpointer measure_data,
const graphene_point_t *point,
gboolean *on_edge)
{
const GskRectContour *self = (const GskRectContour *) contour;
graphene_rect_t rect;
graphene_rect_init (&rect, self->x, self->y, self->width, self->height);
if (graphene_rect_contains_point (&rect, point))
return -1;
return 0;
}
static const GskContourClass GSK_RECT_CONTOUR_CLASS =
{
sizeof (GskRectContour),
@@ -496,7 +517,8 @@ static const GskContourClass GSK_RECT_CONTOUR_CLASS =
gsk_rect_contour_get_point,
gsk_rect_contour_get_closest_point,
gsk_rect_contour_copy,
gsk_rect_contour_add_segment
gsk_rect_contour_add_segment,
gsk_rect_contour_get_winding
};
GskContour *
@@ -785,6 +807,50 @@ gsk_circle_contour_add_segment (const GskContour *contour,
gsk_path_builder_add_contour (builder, segment);
}
static int
gsk_circle_contour_get_winding (const GskContour *contour,
gpointer measure_data,
const graphene_point_t *point,
gboolean *on_edge)
{
const GskCircleContour *self = (const GskCircleContour *) contour;
if (graphene_point_distance (point, &self->center, NULL, NULL) >= self->radius)
return 0;
if (fabs (self->start_angle - self->end_angle) >= 360)
{
return -1;
}
else
{
/* Check if the point and the midpoint are on the same side
* of the chord through start and end.
*/
double mid_angle = (self->end_angle - self->start_angle) / 2;
graphene_point_t start = GRAPHENE_POINT_INIT (self->center.x + cos (DEG_TO_RAD (self->start_angle)) * self->radius,
self->center.y + sin (DEG_TO_RAD (self->start_angle)) * self->radius);
graphene_point_t mid = GRAPHENE_POINT_INIT (self->center.x + cos (DEG_TO_RAD (mid_angle)) * self->radius,
self->center.y + sin (DEG_TO_RAD (mid_angle)) * self->radius);
graphene_point_t end = GRAPHENE_POINT_INIT (self->center.x + cos (DEG_TO_RAD (self->end_angle)) * self->radius,
self->center.y + sin (DEG_TO_RAD (self->end_angle)) * self->radius);
graphene_vec2_t n, m;
float a, b;
graphene_vec2_init (&n, start.y - end.y, end.x - start.x);
graphene_vec2_init (&m, mid.x, mid.y);
a = graphene_vec2_dot (&m, &n);
graphene_vec2_init (&m, point->x, point->y);
b = graphene_vec2_dot (&m, &n);
if ((a < 0) != (b < 0))
return -1;
}
return 0;
}
static const GskContourClass GSK_CIRCLE_CONTOUR_CLASS =
{
sizeof (GskCircleContour),
@@ -800,7 +866,8 @@ static const GskContourClass GSK_CIRCLE_CONTOUR_CLASS =
gsk_circle_contour_get_point,
gsk_circle_contour_get_closest_point,
gsk_circle_contour_copy,
gsk_circle_contour_add_segment
gsk_circle_contour_add_segment,
gsk_circle_contour_get_winding
};
GskContour *
@@ -1440,6 +1507,79 @@ gsk_standard_contour_add_segment (const GskContour *contour,
}
}
static inline int
line_get_crossing (const graphene_point_t *p,
const graphene_point_t *p1,
const graphene_point_t *p2,
gboolean *on_edge)
{
int dir = 1;
if (p1->x >= p->x && p2->x >= p->x)
return 0;
if (p2->y < p1->y)
{
const graphene_point_t *tmp;
tmp = p1;
p1 = p2;
p2 = tmp;
dir = -1;
}
if ((p1->x >= p->x && p1->y == p->y) ||
(p2->x >= p->x && p2->y == p->y))
{
*on_edge = TRUE;
return 0;
}
if (p2->y <= p->y || p1->y > p->y)
return 0;
if (p1->x <= p->x && p2->x <= p->x)
return dir;
if (p->x > p1->x + (p->y - p1->y) * (p2->x - p1->x) / (p2->y - p1->y))
return dir;
return 0;
}
static int
gsk_standard_contour_get_winding (const GskContour *contour,
gpointer measure_data,
const graphene_point_t *point,
gboolean *on_edge)
{
GskStandardContour *self = (GskStandardContour *) contour;
GArray *array = measure_data;
graphene_point_t last_point;
int winding;
int i;
if (array->len == 0)
return 0;
winding = 0;
last_point = self->points[0];
for (i = 0; i < array->len; i++)
{
GskStandardContourMeasure *measure;
measure = &g_array_index (array, GskStandardContourMeasure, i);
winding += line_get_crossing (point, &last_point, &measure->end_point, on_edge);
if (*on_edge)
return 0;
last_point = measure->end_point;
}
winding += line_get_crossing (point, &last_point, &self->points[0], on_edge);
return winding;
}
static const GskContourClass GSK_STANDARD_CONTOUR_CLASS =
{
sizeof (GskStandardContour),
@@ -1455,7 +1595,8 @@ static const GskContourClass GSK_STANDARD_CONTOUR_CLASS =
gsk_standard_contour_get_point,
gsk_standard_contour_get_closest_point,
gsk_standard_contour_copy,
gsk_standard_contour_add_segment
gsk_standard_contour_add_segment,
gsk_standard_contour_get_winding
};
/* You must ensure the contour has enough size allocated,
@@ -1591,6 +1732,15 @@ gsk_contour_add_segment (const GskContour *self,
self->klass->add_segment (self, builder, measure_data, start, end);
}
int
gsk_contour_get_winding (const GskContour *self,
gpointer measure_data,
const graphene_point_t *point,
gboolean *on_edge)
{
return self->klass->get_winding (self, measure_data, point, on_edge);
}
static inline void
gsk_contour_copy (GskContour *dest,
const GskContour *src)

43
gsk/gskpathmeasure.c
View File

@@ -374,6 +374,48 @@ gsk_path_measure_get_closest_point_full (GskPathMeasure *self,
return result;
}
/**
* gsk_path_measure_in_fill:
* @self: a #GskPathMeasure
* @point: the point to test
* @fill_rule: the fill rule to follow
*
* Returns whether the given point is inside the area that would be
* affected if the path of @self was filled according to @fill_rule.
*
* Returns: %TRUE if @point is inside
*/
gboolean
gsk_path_measure_in_fill (GskPathMeasure *self,
const graphene_point_t *point,
GskFillRule fill_rule)
{
int winding = 0;
gboolean on_edge = FALSE;
int i;
for (i = 0; i < self->n_contours; i++)
{
winding += gsk_contour_get_winding (gsk_path_get_contour (self->path, i),
self->measures[i].contour_data,
point,
&on_edge);
if (on_edge)
return TRUE;
}
switch (fill_rule)
{
case GSK_FILL_RULE_EVEN_ODD:
return winding & 1;
case GSK_FILL_RULE_WINDING:
return winding != 0;
default:
g_assert_not_reached ();
}
}
/**
* gsk_path_measure_add_segment:
* @self: a #GskPathMeasure
@@ -433,4 +475,3 @@ gsk_path_measure_add_segment (GskPathMeasure *self,
}
}
}

5
gsk/gskpathmeasure.h
View File

@@ -70,6 +70,11 @@ void gsk_path_measure_add_segment (GskPathMeasure
float start,
float end);
GDK_AVAILABLE_IN_ALL
gboolean gsk_path_measure_in_fill (GskPathMeasure *self,
const graphene_point_t *point,
GskFillRule fill_rule);
G_DEFINE_AUTOPTR_CLEANUP_FUNC(GskPathMeasure, gsk_path_measure_unref)
G_END_DECLS

4
gsk/gskpathprivate.h
View File

@@ -92,6 +92,10 @@ gboolean gsk_contour_get_closest_point (GskPath
graphene_point_t *out_pos,
float *out_offset,
graphene_vec2_t *out_tangent);
int gsk_contour_get_winding (const GskContour *self,
gpointer measure_data,
const graphene_point_t *point,
gboolean *on_edge);
void gsk_contour_add_segment (const GskContour *self,
GskPathBuilder *builder,
gpointer measure_data,