Learning_GTK4_tree/gsk/gskcontour.c

2637 lines
75 KiB
C

/*
* Copyright © 2020 Benjamin Otte
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library. If not, see <http://www.gnu.org/licenses/>.
*
* Authors: Benjamin Otte <otte@gnome.org>
*/
#include "config.h"
#include "gskcontourprivate.h"
#include "gskcurveprivate.h"
#include "gskpathbuilder.h"
#include "gskpathprivate.h"
#include "gskpathpoint.h"
#include "gskstrokeprivate.h"
#include <float.h>
/* This is C11 */
#ifndef FLT_DECIMAL_DIG
#define FLT_DECIMAL_DIG 9
#endif
typedef struct _GskContourClass GskContourClass;
struct _GskContour
{
const GskContourClass *klass;
};
struct _GskContourClass
{
gsize struct_size;
const char *type_name;
void (* copy) (const GskContour *contour,
GskContour *dest);
gsize (* get_size) (const GskContour *contour);
GskPathFlags (* get_flags) (const GskContour *contour);
void (* print) (const GskContour *contour,
GString *string);
gboolean (* get_bounds) (const GskContour *contour,
GskBoundingBox *bounds);
gboolean (* get_stroke_bounds) (const GskContour *contour,
const GskStroke *stroke,
GskBoundingBox *bounds);
gboolean (* foreach) (const GskContour *contour,
GskPathForeachFunc func,
gpointer user_data);
GskContour * (* reverse) (const GskContour *contour);
int (* get_winding) (const GskContour *contour,
const graphene_point_t *point);
gsize (* get_n_ops) (const GskContour *contour);
gboolean (* get_closest_point) (const GskContour *contour,
const graphene_point_t *point,
float threshold,
GskPathPoint *result,
float *out_dist);
void (* get_position) (const GskContour *contour,
const GskPathPoint *point,
graphene_point_t *position);
void (* get_tangent) (const GskContour *contour,
const GskPathPoint *point,
GskPathDirection direction,
graphene_vec2_t *tangent);
float (* get_curvature) (const GskContour *contour,
const GskPathPoint *point,
GskPathDirection direction,
graphene_point_t *center);
void (* add_segment) (const GskContour *contour,
GskPathBuilder *builder,
gboolean emit_move_to,
const GskPathPoint *start,
const GskPathPoint *end);
gpointer (* init_measure) (const GskContour *contour,
float tolerance,
float *out_length);
void (* free_measure) (const GskContour *contour,
gpointer measure_data);
void (* get_point) (const GskContour *contour,
gpointer measure_data,
float distance,
GskPathPoint *result);
float (* get_distance) (const GskContour *contour,
const GskPathPoint *point,
gpointer measure_data);
};
/* {{{ Utilities */
#define DEG_TO_RAD(x) ((x) * (G_PI / 180.f))
#define RAD_TO_DEG(x) ((x) / (G_PI / 180.f))
static inline void
_sincosf (float angle,
float *out_s,
float *out_c)
{
#ifdef HAVE_SINCOSF
sincosf (angle, out_s, out_c);
#else
*out_s = sinf (angle);
*out_c = cosf (angle);
#endif
}
static void
_g_string_append_float (GString *string,
const char *prefix,
float f)
{
g_string_append (string, prefix);
g_string_append_printf (string, "%.*g", FLT_DECIMAL_DIG, f);
}
static void
_g_string_append_point (GString *string,
const char *prefix,
const graphene_point_t *pt)
{
_g_string_append_float (string, prefix, pt->x);
_g_string_append_float (string, " ", pt->y);
}
static gboolean
add_segment (GskPathOperation op,
const graphene_point_t *pts,
gsize n_pts,
float weight,
gpointer user_data)
{
GskPathBuilder *builder = user_data;
switch (op)
{
case GSK_PATH_MOVE:
gsk_path_builder_move_to (builder, pts[0].x, pts[0].y);
break;
case GSK_PATH_LINE:
gsk_path_builder_line_to (builder, pts[1].x, pts[1].y);
break;
case GSK_PATH_QUAD:
gsk_path_builder_quad_to (builder,
pts[1].x, pts[1].y,
pts[2].x, pts[2].y);
break;
case GSK_PATH_CUBIC:
gsk_path_builder_cubic_to (builder,
pts[1].x, pts[1].y,
pts[2].x, pts[2].y,
pts[3].x, pts[3].y);
break;
case GSK_PATH_CONIC:
gsk_path_builder_conic_to (builder,
pts[1].x, pts[1].y,
pts[2].x, pts[2].y,
weight);
break;
case GSK_PATH_CLOSE:
gsk_path_builder_close (builder);
break;
default:
g_assert_not_reached ();
}
return TRUE;
}
static GskPath *
convert_to_standard_contour (const GskContour *contour)
{
GskPathBuilder *builder;
builder = gsk_path_builder_new ();
gsk_contour_foreach (contour, add_segment, builder);
return gsk_path_builder_free_to_path (builder);
}
typedef struct
{
GskCurve *curve;
unsigned int idx;
unsigned int count;
} InitCurveData;
static gboolean
init_curve_cb (GskPathOperation op,
const graphene_point_t *pts,
gsize n_pts,
float weight,
gpointer user_data)
{
InitCurveData *data = user_data;
if (data->idx == data->count)
{
gsk_curve_init_foreach (data->curve, op, pts, n_pts, weight);
return FALSE;
}
data->count++;
return TRUE;
}
static void
contour_init_curve (const GskContour *contour,
unsigned int idx,
GskCurve *curve)
{
InitCurveData data;
data.curve = curve;
data.idx = idx;
data.count = 0;
gsk_contour_foreach (contour, init_curve_cb, &data);
}
typedef struct
{
graphene_point_t point;
float threshold;
gsize idx;
gsize best_idx;
gsize best_t;
} ClosestPointData;
static gboolean
get_closest_point_cb (GskPathOperation op,
const graphene_point_t *pts,
gsize n_pts,
float weight,
gpointer data)
{
GskCurve curve;
ClosestPointData *pd = data;
float distance, t;
if (op == GSK_PATH_MOVE)
return TRUE;
pd->idx++;
gsk_curve_init_foreach (&curve, op, pts, n_pts, weight);
if (gsk_curve_get_closest_point (&curve, &pd->point, pd->threshold, &distance, &t) &&
distance < pd->threshold)
{
pd->best_idx = pd->idx;
pd->best_t = t;
pd->threshold = distance;
}
return TRUE;
}
static gboolean
contour_get_closest_point (const GskContour *contour,
const graphene_point_t *point,
float threshold,
GskPathPoint *result,
float *out_dist)
{
ClosestPointData pd;
pd.point = *point;
pd.threshold = threshold;
pd.idx = 0;
pd.best_idx = G_MAXUINT;
gsk_contour_foreach (contour, get_closest_point_cb, &pd);
if (pd.best_idx != G_MAXUINT)
{
result->idx = pd.best_idx;
result->t = pd.best_t;
*out_dist = pd.threshold;
return TRUE;
}
return FALSE;
}
static void
add_curve (GskCurve *curve,
GskPathBuilder *builder,
gboolean *emit_move_to)
{
if (*emit_move_to)
{
const graphene_point_t *s;
s = gsk_curve_get_start_point (curve);
gsk_path_builder_move_to (builder, s->x, s->y);
*emit_move_to = FALSE;
}
gsk_curve_builder_to (curve, builder);
}
typedef struct
{
GskPathBuilder *builder;
gboolean emit_move_to;
GskPathPoint start;
GskPathPoint end;
gsize idx;
} AddSegmentData;
static gboolean
add_segment_cb (GskPathOperation op,
const graphene_point_t *pts,
gsize n_pts,
float weight,
gpointer data)
{
AddSegmentData *sd = data;
GskCurve c, c1, c2;
if (op == GSK_PATH_MOVE)
return TRUE;
sd->idx++;
if (sd->start.idx > sd->idx)
return TRUE;
if (sd->end.idx < sd->idx)
return FALSE;
if (op == GSK_PATH_CLOSE)
op = GSK_PATH_LINE;
gsk_curve_init_foreach (&c, op, pts, n_pts, weight);
if (sd->start.idx == sd->idx)
{
if (sd->end.idx == sd->idx)
{
gsk_curve_segment (&c, sd->start.t, sd->end.t, &c1);
add_curve (&c1, sd->builder, &sd->emit_move_to);
return FALSE;
}
else
{
gsk_curve_split (&c, sd->start.t, &c1, &c2);
add_curve (&c2, sd->builder, &sd->emit_move_to);
return TRUE;
}
}
else
{
if (sd->end.idx == sd->idx)
{
gsk_curve_split (&c, sd->end.t, &c1, &c2);
add_curve (&c1, sd->builder, &sd->emit_move_to);
return FALSE;
}
else
{
add_curve (&c, sd->builder, &sd->emit_move_to);
return TRUE;
}
}
}
static void
contour_add_segment (const GskContour *contour,
GskPathBuilder *builder,
gboolean emit_move_to,
const GskPathPoint *start,
const GskPathPoint *end)
{
AddSegmentData sd;
sd.builder = builder;
sd.emit_move_to = emit_move_to;
sd.start = *start;
sd.end = *end;
sd.idx = 0;
gsk_contour_foreach (contour, add_segment_cb, &sd);
}
static inline gboolean
maybe_emit_line (const graphene_point_t pts[2],
GskPathForeachFunc func,
gpointer user_data)
{
if (graphene_point_equal (&pts[0], &pts[1]))
return TRUE;
return func (GSK_PATH_LINE, pts, 2, 0.f, user_data);
}
static inline gboolean
maybe_emit_conic (const graphene_point_t pts[3],
float weight,
GskPathForeachFunc func,
gpointer user_data)
{
if (graphene_point_equal (&pts[0], &pts[1]))
{
if (graphene_point_equal (&pts[1], &pts[2]))
return TRUE;
else
return func (GSK_PATH_LINE, &pts[1], 2, 0.f, user_data);
}
else if (graphene_point_equal (&pts[1], &pts[2]))
return func (GSK_PATH_LINE, &pts[0], 2, 0.f, user_data);
return func (GSK_PATH_CONIC, pts, 3, weight, user_data);
}
/* Assumes a closed contour */
static void
apply_corner_direction (GskPathDirection direction,
gsize *idx,
float *t,
gsize n_ops)
{
if (*t == 0 &&
(direction == GSK_PATH_FROM_START || direction == GSK_PATH_TO_START))
{
if (*idx > 1)
*idx = *idx - 1;
else
*idx = n_ops - 1;
*t = 1;
}
else if (*t == 1 &&
(direction == GSK_PATH_FROM_END || direction == GSK_PATH_TO_END))
{
if (*idx < n_ops - 1)
*idx = *idx + 1;
else
*idx = 1;
*t = 0;
}
}
/* }}} */
/* {{{ Default implementations */
static gsize
gsk_contour_get_size_default (const GskContour *contour)
{
return contour->klass->struct_size;
}
static gboolean
foreach_print (GskPathOperation op,
const graphene_point_t *pts,
gsize n_pts,
float weight,
gpointer data)
{
GString *string = data;
switch (op)
{
case GSK_PATH_MOVE:
_g_string_append_point (string, "M ", &pts[0]);
break;
case GSK_PATH_CLOSE:
g_string_append (string, " Z");
break;
case GSK_PATH_LINE:
_g_string_append_point (string, " L ", &pts[1]);
break;
case GSK_PATH_QUAD:
_g_string_append_point (string, " Q ", &pts[1]);
_g_string_append_point (string, ", ", &pts[2]);
break;
case GSK_PATH_CUBIC:
_g_string_append_point (string, " C ", &pts[1]);
_g_string_append_point (string, ", ", &pts[2]);
_g_string_append_point (string, ", ", &pts[3]);
break;
case GSK_PATH_CONIC:
_g_string_append_point (string, " O ", &pts[1]);
_g_string_append_point (string, ", ", &pts[2]);
_g_string_append_float (string, ", ", weight);
break;
default:
g_assert_not_reached ();
}
return TRUE;
}
static void
gsk_contour_print_default (const GskContour *contour,
GString *string)
{
gsk_contour_foreach (contour, foreach_print, string);
}
/* }}} */
/* {{{ Standard */
typedef struct _GskStandardContour GskStandardContour;
struct _GskStandardContour
{
GskContour contour;
GskPathFlags flags;
GskBoundingBox bounds;
gsize n_ops;
gsize n_points;
graphene_point_t *points;
gskpathop ops[];
};
static gsize
gsk_standard_contour_compute_size (gsize n_ops,
gsize n_points)
{
gsize align = MAX (G_ALIGNOF (graphene_point_t),
MAX (G_ALIGNOF (gpointer),
G_ALIGNOF (GskStandardContour)));
gsize s = sizeof (GskStandardContour)
+ sizeof (gskpathop) * n_ops
+ sizeof (graphene_point_t) * n_points;
return s + (align - (s % align));
}
static void
gsk_standard_contour_init (GskContour *contour,
GskPathFlags flags,
const graphene_point_t *points,
gsize n_points,
const gskpathop *ops,
gsize n_ops,
ptrdiff_t offset);
static void
gsk_standard_contour_copy (const GskContour *contour,
GskContour *dest)
{
const GskStandardContour *self = (const GskStandardContour *) contour;
gsk_standard_contour_init (dest, self->flags, self->points, self->n_points, self->ops, self->n_ops, 0);
}
static gsize
gsk_standard_contour_get_size (const GskContour *contour)
{
const GskStandardContour *self = (const GskStandardContour *) contour;
return gsk_standard_contour_compute_size (self->n_ops, self->n_points);
}
static gboolean
gsk_standard_contour_foreach (const GskContour *contour,
GskPathForeachFunc func,
gpointer user_data)
{
const GskStandardContour *self = (const GskStandardContour *) contour;
gsize i;
for (i = 0; i < self->n_ops; i ++)
{
if (!gsk_pathop_foreach (self->ops[i], func, user_data))
return FALSE;
}
return TRUE;
}
static gboolean
add_reverse (GskPathOperation op,
const graphene_point_t *pts,
gsize n_pts,
float weight,
gpointer user_data)
{
GskPathBuilder *builder = user_data;
GskCurve c, r;
if (op == GSK_PATH_MOVE)
return TRUE;
if (op == GSK_PATH_CLOSE)
op = GSK_PATH_LINE;
gsk_curve_init_foreach (&c, op, pts, n_pts, weight);
gsk_curve_reverse (&c, &r);
gsk_curve_builder_to (&r, builder);
return TRUE;
}
static GskContour *
gsk_standard_contour_reverse (const GskContour *contour)
{
const GskStandardContour *self = (const GskStandardContour *) contour;
GskPathBuilder *builder;
GskPath *path;
GskContour *res;
builder = gsk_path_builder_new ();
gsk_path_builder_move_to (builder, self->points[self->n_points - 1].x,
self->points[self->n_points - 1].y);
for (int i = self->n_ops - 1; i >= 0; i--)
gsk_pathop_foreach (self->ops[i], add_reverse, builder);
if (self->flags & GSK_PATH_CLOSED)
gsk_path_builder_close (builder);
path = gsk_path_builder_free_to_path (builder);
g_assert (gsk_path_get_n_contours (path) == 1);
res = gsk_contour_dup (gsk_path_get_contour (path, 0));
gsk_path_unref (path);
return res;
}
static GskPathFlags
gsk_standard_contour_get_flags (const GskContour *contour)
{
const GskStandardContour *self = (const GskStandardContour *) contour;
return self->flags;
}
static gboolean
gsk_standard_contour_get_bounds (const GskContour *contour,
GskBoundingBox *bounds)
{
const GskStandardContour *self = (const GskStandardContour *) contour;
if (self->n_points == 0)
return FALSE;
*bounds = self->bounds;
return bounds->max.x > bounds->min.x && bounds->max.y > bounds->min.y;
}
static gboolean
gsk_standard_contour_get_stroke_bounds (const GskContour *contour,
const GskStroke *stroke,
GskBoundingBox *bounds)
{
GskStandardContour *self = (GskStandardContour *) contour;
float extra;
if (self->n_points == 0)
return FALSE;
extra = MAX (stroke->line_width, gsk_stroke_get_join_width (stroke));
gsk_bounding_box_init (bounds, &GRAPHENE_POINT_INIT (self->bounds.min.x - extra,
self->bounds.min.y - extra),
&GRAPHENE_POINT_INIT (self->bounds.max.x + extra,
self->bounds.max.y + extra));
return TRUE;
}
static int
gsk_standard_contour_get_winding (const GskContour *contour,
const graphene_point_t *point)
{
GskStandardContour *self = (GskStandardContour *) contour;
int winding = 0;
if (!gsk_bounding_box_contains_point (&self->bounds, point))
return 0;
for (gsize i = 0; i < self->n_ops; i ++)
{
GskCurve c;
if (gsk_pathop_op (self->ops[i]) == GSK_PATH_MOVE)
continue;
gsk_curve_init (&c, self->ops[i]);
winding += gsk_curve_get_crossing (&c, point);
}
if ((self->flags & GSK_PATH_CLOSED) == 0)
{
GskCurve c;
gsk_curve_init (&c, gsk_pathop_encode (GSK_PATH_CLOSE,
(const graphene_point_t[]) { self->points[self->n_points - 1],
self->points[0] }));
winding += gsk_curve_get_crossing (&c, point);
}
return winding;
}
static gsize
gsk_standard_contour_get_n_ops (const GskContour *contour)
{
GskStandardContour *self = (GskStandardContour *) contour;
return self->n_ops;
}
static gboolean
gsk_standard_contour_get_closest_point (const GskContour *contour,
const graphene_point_t *point,
float threshold,
GskPathPoint *result,
float *out_dist)
{
GskStandardContour *self = (GskStandardContour *) contour;
unsigned int best_idx = G_MAXUINT;
float best_t = 0;
g_assert (gsk_pathop_op (self->ops[0]) == GSK_PATH_MOVE);
if (self->n_ops == 1)
{
float dist;
dist = graphene_point_distance (point, &self->points[0], NULL, NULL);
if (dist <= threshold)
{
*out_dist = dist;
result->idx = 0;
result->t = 1;
return TRUE;
}
return FALSE;
}
for (gsize i = 0; i < self->n_ops; i ++)
{
GskCurve c;
float distance, t;
if (gsk_pathop_op (self->ops[i]) == GSK_PATH_MOVE)
continue;
gsk_curve_init (&c, self->ops[i]);
if (gsk_curve_get_closest_point (&c, point, threshold, &distance, &t) &&
distance < threshold)
{
best_idx = i;
best_t = t;
threshold = distance;
}
}
if (best_idx != G_MAXUINT)
{
*out_dist = threshold;
result->idx = best_idx;
result->t = best_t;
return TRUE;
}
return FALSE;
}
static void
gsk_standard_contour_get_position (const GskContour *contour,
const GskPathPoint *point,
graphene_point_t *position)
{
GskStandardContour *self = (GskStandardContour *) contour;
GskCurve curve;
if (G_UNLIKELY (point->idx == 0))
{
*position = self->points[0];
return;
}
gsk_curve_init (&curve, self->ops[point->idx]);
gsk_curve_get_point (&curve, point->t, position);
}
static void
gsk_standard_contour_get_tangent (const GskContour *contour,
const GskPathPoint *point,
GskPathDirection direction,
graphene_vec2_t *tangent)
{
GskStandardContour *self = (GskStandardContour *) contour;
GskCurve curve;
gsize idx;
float t;
if (G_UNLIKELY (point->idx == 0))
{
graphene_vec2_init (tangent, 0, 0);
return;
}
idx = point->idx;
t = point->t;
if (t == 0 && (direction == GSK_PATH_FROM_START ||
direction == GSK_PATH_TO_START))
{
/* Look at the previous segment */
if (idx > 1)
{
idx--;
t = 1;
}
else if (self->flags & GSK_PATH_CLOSED)
{
idx = self->n_ops - 1;
t = 1;
}
}
else if (t == 1 && (direction == GSK_PATH_TO_END ||
direction == GSK_PATH_FROM_END))
{
/* Look at the next segment */
if (idx < self->n_ops - 1)
{
idx++;
t = 0;
}
else if (self->flags & GSK_PATH_CLOSED)
{
idx = 1;
t = 0;
}
}
gsk_curve_init (&curve, self->ops[idx]);
gsk_curve_get_tangent (&curve, t, tangent);
if (direction == GSK_PATH_TO_START || direction == GSK_PATH_FROM_END)
graphene_vec2_negate (tangent, tangent);
}
static float
gsk_standard_contour_get_curvature (const GskContour *contour,
const GskPathPoint *point,
GskPathDirection direction,
graphene_point_t *center)
{
GskStandardContour *self = (GskStandardContour *) contour;
GskCurve curve;
gsize idx;
float t;
if (G_UNLIKELY (point->idx == 0))
return 0;
idx = point->idx;
t = point->t;
if (t == 0 && idx > 1 &&
(direction == GSK_PATH_FROM_START || direction == GSK_PATH_TO_START))
{
idx--;
t = 1;
}
else if (t == 1 && idx + 1 < self->n_ops &&
(direction == GSK_PATH_FROM_END || direction == GSK_PATH_TO_END))
{
idx++;
t = 0;
}
gsk_curve_init (&curve, self->ops[idx]);
return gsk_curve_get_curvature (&curve, t, center);
}
static void
gsk_standard_contour_add_segment (const GskContour *contour,
GskPathBuilder *builder,
gboolean emit_move_to,
const GskPathPoint *start,
const GskPathPoint *end)
{
GskStandardContour *self = (GskStandardContour *) contour;
GskCurve c, c1, c2;
g_assert (start->idx < self->n_ops);
g_assert (end->idx < self->n_ops);
gsk_curve_init (&c, self->ops[start->idx]);
if (start->idx == end->idx)
{
gsk_curve_segment (&c, start->t, end->t, &c1);
add_curve (&c1, builder, &emit_move_to);
return;
}
if (start->t == 0)
{
add_curve (&c, builder, &emit_move_to);
}
else if (start->t < 1)
{
gsk_curve_split (&c, start->t, &c1, &c2);
add_curve (&c2, builder, &emit_move_to);
}
for (gsize i = start->idx + 1; i < end->idx; i++)
{
gsk_curve_init (&c, self->ops[i]);
add_curve (&c, builder, &emit_move_to);
}
gsk_curve_init (&c, self->ops[end->idx]);
if (c.op == GSK_PATH_CLOSE)
c.op = GSK_PATH_LINE;
if (end->t == 1)
{
add_curve (&c, builder, &emit_move_to);
}
else if (end->t > 0)
{
gsk_curve_split (&c, end->t, &c1, &c2);
add_curve (&c1, builder, &emit_move_to);
}
}
typedef struct
{
gsize idx;
float length0;
float length1;
gsize n_samples;
gsize first;
} CurveMeasure;
typedef struct
{
float t;
float length;
} CurvePoint;
typedef struct
{
GArray *curves;
GArray *points;
float tolerance;
} GskStandardContourMeasure;
static void
add_measure (const GskCurve *curve,
gsize idx,
float length,
float tolerance,
float t1,
float l1,
GArray *array)
{
GskCurve c;
float ll, l0;
float t0;
CurvePoint *p;
/* Check if we can add (t1, length + l1) without further
* splitting. We check two things:
* - Is the curve close to a straight line (length-wise) ?
* - Does the roundtrip length<>t not deviate too much ?
*/
if (curve->op == GSK_PATH_LINE ||
curve->op == GSK_PATH_CLOSE)
goto done;
p = &g_array_index (array, CurvePoint, array->len - 1);
t0 = (p->t + t1) / 2;
if (t0 == p->t || t0 == t1)
goto done;
gsk_curve_split (curve, t0, &c, NULL);
l0 = gsk_curve_get_length (&c);
ll = (p->length + length + l1) / 2;
if (fabsf (length + l0 - ll) < tolerance)
{
done:
g_array_append_val (array, ((CurvePoint) { t1, length + l1 }));
}
else
{
add_measure (curve, idx, length, tolerance, t0, l0, array);
add_measure (curve, idx, length, tolerance, t1, l1, array);
}
}
static int
cmpfloat (const void *p1, const void *p2)
{
const float *f1 = p1;
const float *f2 = p2;
return *f1 < *f2 ? -1 : (*f1 > *f2 ? 1 : 0);
}
static void
add_samples (const GskStandardContour *self,
GskStandardContourMeasure *measure,
CurveMeasure *curve_measure)
{
gsize first;
GskCurve curve;
float l0, l1;
float t[3];
int n;
g_assert (curve_measure->n_samples == 0);
g_assert (0 < curve_measure->idx && curve_measure->idx < self->n_ops);
first = measure->points->len;
l0 = curve_measure->length0;
l1 = curve_measure->length1;
g_array_append_val (measure->points, ((CurvePoint) { 0, l0 } ));
gsk_curve_init (&curve, self->ops[curve_measure->idx]);
n = gsk_curve_get_curvature_points (&curve, t);
qsort (t, n, sizeof (float), cmpfloat);
for (int j = 0; j < n; j++)
{
float l = gsk_curve_get_length_to (&curve, t[j]);
add_measure (&curve, curve_measure->idx, l0, measure->tolerance, t[j], l, measure->points);
}
add_measure (&curve, curve_measure->idx, l0, measure->tolerance, 1, l1 - l0, measure->points);
curve_measure->first = first;
curve_measure->n_samples = measure->points->len - first;
}
static void
ensure_samples (const GskStandardContour *self,
GskStandardContourMeasure *measure,
CurveMeasure *curve_measure)
{
if (curve_measure->n_samples == 0)
add_samples (self, measure, curve_measure);
}
static gpointer
gsk_standard_contour_init_measure (const GskContour *contour,
float tolerance,
float *out_length)
{
const GskStandardContour *self = (const GskStandardContour *) contour;
GskStandardContourMeasure *measure;
float length;
measure = g_new (GskStandardContourMeasure, 1);
measure->curves = g_array_new (FALSE, FALSE, sizeof (CurveMeasure));
measure->points = g_array_new (FALSE, FALSE, sizeof (CurvePoint));
measure->tolerance = tolerance;
/* Add a placeholder for the move, so indexes match up */
g_array_append_val (measure->curves, ((CurveMeasure) { 0, -1, -1, 0, 0 } ));
length = 0;
for (gsize i = 1; i < self->n_ops; i++)
{
GskCurve curve;
float l;
gsk_curve_init (&curve, self->ops[i]);
l = gsk_curve_get_length (&curve);
g_array_append_val (measure->curves, ((CurveMeasure) { i, length, length + l, 0, 0 } ));
length += l;
}
*out_length = length;
return measure;
}
static void
gsk_standard_contour_free_measure (const GskContour *contour,
gpointer data)
{
GskStandardContourMeasure *measure = data;
g_array_free (measure->curves, TRUE);
g_array_free (measure->points, TRUE);
g_free (measure);
}
static int
find_curve (gconstpointer a,
gconstpointer b)
{
const CurveMeasure *m = a;
const float distance = *(const float *) b;
if (distance < m->length0)
return 1;
else if (distance > m->length1)
return -1;
else
return 0;
}
static void
gsk_standard_contour_get_point (const GskContour *contour,
gpointer measure_data,
float distance,
GskPathPoint *result)
{
const GskStandardContour *self = (const GskStandardContour *) contour;
GskStandardContourMeasure *measure = measure_data;
CurveMeasure *curve_measure;
gboolean found G_GNUC_UNUSED;
guint idx;
gsize i0, i1;
CurvePoint *p0, *p1;
if (self->n_ops == 1)
{
result->idx = 0;
result->t = 1;
return;
}
found = g_array_binary_search (measure->curves, &distance, find_curve, &idx);
g_assert (found);
curve_measure = &g_array_index (measure->curves, CurveMeasure, idx);
ensure_samples (self, measure, curve_measure);
i0 = curve_measure->first;
i1 = curve_measure->first + curve_measure->n_samples - 1;
while (i0 + 1 < i1)
{
gsize i = (i0 + i1) / 2;
CurvePoint *p = &g_array_index (measure->points, CurvePoint, i);
if (p->length < distance)
i0 = i;
else if (p->length > distance)
i1 = i;
else
{
result->idx = curve_measure->idx;
result->t = p->t;
g_assert (0 <= result->t && result->t <= 1);
return;
}
}
p0 = &g_array_index (measure->points, CurvePoint, i0);
p1 = &g_array_index (measure->points, CurvePoint, i1);
if (distance >= p1->length)
{
if (curve_measure->idx == self->n_ops - 1)
{
result->idx = curve_measure->idx;
result->t = 1;
}
else
{
result->idx = curve_measure->idx + 1;
result->t = 0;
}
}
else
{
float fraction;
result->idx = curve_measure->idx;
fraction = (distance - p0->length) / (p1->length - p0->length);
g_assert (fraction >= 0 && fraction <= 1);
result->t = p0->t * (1 - fraction) + p1->t * fraction;
g_assert (result->t >= 0 && result->t <= 1);
}
}
static float
gsk_standard_contour_get_distance (const GskContour *contour,
const GskPathPoint *point,
gpointer measure_data)
{
const GskStandardContour *self = (const GskStandardContour *) contour;
GskStandardContourMeasure *measure = measure_data;
CurveMeasure *curve_measure;
gsize i0, i1;
CurvePoint *p0, *p1;
float fraction;
if (G_UNLIKELY (point->idx == 0))
return 0;
curve_measure = &g_array_index (measure->curves, CurveMeasure, point->idx);
ensure_samples (self, measure, curve_measure);
i0 = curve_measure->first;
i1 = curve_measure->first + curve_measure->n_samples - 1;
while (i0 + 1 < i1)
{
gsize i = (i0 + i1) / 2;
CurvePoint *p = &g_array_index (measure->points, CurvePoint, i);
if (p->t > point->t)
i1 = i;
else if (p->t < point->t)
i0 = i;
else
return p->length;
}
p0 = &g_array_index (measure->points, CurvePoint, i0);
p1 = &g_array_index (measure->points, CurvePoint, i1);
g_assert (p0->t <= point->t && point->t <= p1->t);
fraction = (point->t - p0->t) / (p1->t - p0->t);
g_assert (fraction >= 0 && fraction <= 1);
return p0->length * (1 - fraction) + p1->length * fraction;
}
static const GskContourClass GSK_STANDARD_CONTOUR_CLASS =
{
sizeof (GskStandardContour),
"GskStandardContour",
gsk_standard_contour_copy,
gsk_standard_contour_get_size,
gsk_standard_contour_get_flags,
gsk_contour_print_default,
gsk_standard_contour_get_bounds,
gsk_standard_contour_get_stroke_bounds,
gsk_standard_contour_foreach,
gsk_standard_contour_reverse,
gsk_standard_contour_get_winding,
gsk_standard_contour_get_n_ops,
gsk_standard_contour_get_closest_point,
gsk_standard_contour_get_position,
gsk_standard_contour_get_tangent,
gsk_standard_contour_get_curvature,
gsk_standard_contour_add_segment,
gsk_standard_contour_init_measure,
gsk_standard_contour_free_measure,
gsk_standard_contour_get_point,
gsk_standard_contour_get_distance,
};
/* You must ensure the contour has enough size allocated,
* see gsk_standard_contour_compute_size()
*/
static void
gsk_standard_contour_init (GskContour *contour,
GskPathFlags flags,
const graphene_point_t *points,
gsize n_points,
const gskpathop *ops,
gsize n_ops,
gssize offset)
{
GskStandardContour *self = (GskStandardContour *) contour;
self->contour.klass = &GSK_STANDARD_CONTOUR_CLASS;
self->flags = flags;
self->n_ops = n_ops;
self->n_points = n_points;
self->points = (graphene_point_t *) &self->ops[n_ops];
memcpy (self->points, points, sizeof (graphene_point_t) * n_points);
offset += self->points - points;
for (gsize i = 0; i < n_ops; i++)
self->ops[i] = gsk_pathop_encode (gsk_pathop_op (ops[i]),
gsk_pathop_points (ops[i]) + offset);
gsk_bounding_box_init (&self->bounds, &self->points[0], &self->points[0]);
for (gsize i = 1; i < self->n_points; i ++)
gsk_bounding_box_expand (&self->bounds, &self->points[i]);
}
GskContour *
gsk_standard_contour_new (GskPathFlags flags,
const graphene_point_t *points,
gsize n_points,
const gskpathop *ops,
gsize n_ops,
gssize offset)
{
GskContour *contour;
contour = g_malloc0 (gsk_standard_contour_compute_size (n_ops, n_points));
gsk_standard_contour_init (contour, flags, points, n_points, ops, n_ops, offset);
return contour;
}
/* }}} */
/* {{{ Circle */
typedef struct _GskCircleContour GskCircleContour;
struct _GskCircleContour
{
GskContour contour;
graphene_point_t center;
float radius;
gboolean ccw;
};
static void
gsk_circle_contour_copy (const GskContour *contour,
GskContour *dest)
{
const GskCircleContour *self = (const GskCircleContour *) contour;
GskCircleContour *target = (GskCircleContour *) dest;
*target = *self;
}
static GskPathFlags
gsk_circle_contour_get_flags (const GskContour *contour)
{
return GSK_PATH_CLOSED;
}
static void
gsk_circle_contour_print (const GskContour *contour,
GString *string)
{
const GskCircleContour *self = (const GskCircleContour *) contour;
float radius, radius_neg;
if (self->radius > 0)
{
radius = self->radius;
radius_neg = - self->radius;
}
else
{
radius = 0.f;
radius_neg = 0.f;
}
_g_string_append_point (string, "M ", &GRAPHENE_POINT_INIT (self->center.x + radius, self->center.y));
_g_string_append_point (string, " o ", &GRAPHENE_POINT_INIT (0, radius));
_g_string_append_point (string, ", ", &GRAPHENE_POINT_INIT (radius_neg, radius));
_g_string_append_float (string, ", ", M_SQRT1_2);
_g_string_append_point (string, " o ", &GRAPHENE_POINT_INIT (radius_neg, 0));
_g_string_append_point (string, ", ", &GRAPHENE_POINT_INIT (radius_neg, radius_neg));
_g_string_append_float (string, ", ", M_SQRT1_2);
_g_string_append_point (string, " o ", &GRAPHENE_POINT_INIT (0, radius_neg));
_g_string_append_point (string, ", ", &GRAPHENE_POINT_INIT (radius, radius_neg));
_g_string_append_float (string, ", ", M_SQRT1_2);
_g_string_append_point (string, " o ", &GRAPHENE_POINT_INIT (radius, 0));
_g_string_append_point (string, ", ", &GRAPHENE_POINT_INIT (radius, radius));
_g_string_append_float (string, ", ", M_SQRT1_2);
g_string_append (string, " z");
}
static gboolean
gsk_circle_contour_get_bounds (const GskContour *contour,
GskBoundingBox *bounds)
{
const GskCircleContour *self = (const GskCircleContour *) contour;
gsk_bounding_box_init (bounds,
&GRAPHENE_POINT_INIT (self->center.x - self->radius,
self->center.y - self->radius),
&GRAPHENE_POINT_INIT (self->center.x + self->radius,
self->center.y + self->radius));
return TRUE;
}
static gboolean
gsk_circle_contour_get_stroke_bounds (const GskContour *contour,
const GskStroke *stroke,
GskBoundingBox *bounds)
{
const GskCircleContour *self = (const GskCircleContour *) contour;
gsk_bounding_box_init (bounds,
&GRAPHENE_POINT_INIT (self->center.x - self->radius - stroke->line_width,
self->center.y - self->radius - stroke->line_width),
&GRAPHENE_POINT_INIT (self->center.x + self->radius + stroke->line_width/2,
self->center.y + self->radius + stroke->line_width));
return TRUE;
}
static gboolean
gsk_circle_contour_foreach (const GskContour *contour,
GskPathForeachFunc func,
gpointer user_data)
{
const GskCircleContour *self = (const GskCircleContour *) contour;
float rx, ry;
graphene_point_t pts[10];
rx = ry = self->radius;
if (self->ccw)
ry = - self->radius;
pts[0] = GRAPHENE_POINT_INIT (self->center.x + rx, self->center.y);
pts[1] = GRAPHENE_POINT_INIT (self->center.x + rx, self->center.y + ry);
pts[2] = GRAPHENE_POINT_INIT (self->center.x, self->center.y + ry);
pts[3] = GRAPHENE_POINT_INIT (self->center.x - rx, self->center.y + ry);
pts[4] = GRAPHENE_POINT_INIT (self->center.x - rx, self->center.y);
pts[5] = GRAPHENE_POINT_INIT (self->center.x - rx, self->center.y - ry);
pts[6] = GRAPHENE_POINT_INIT (self->center.x, self->center.y - ry);
pts[7] = GRAPHENE_POINT_INIT (self->center.x + rx, self->center.y - ry);
pts[8] = GRAPHENE_POINT_INIT (self->center.x + rx, self->center.y);
pts[9] = GRAPHENE_POINT_INIT (self->center.x + rx, self->center.y);
return func (GSK_PATH_MOVE, &pts[0], 1, 0.f, user_data) &&
maybe_emit_conic (&pts[0], M_SQRT1_2, func, user_data) &&
maybe_emit_conic (&pts[2], M_SQRT1_2, func, user_data) &&
maybe_emit_conic (&pts[4], M_SQRT1_2, func, user_data) &&
maybe_emit_conic (&pts[6], M_SQRT1_2, func, user_data) &&
func (GSK_PATH_CLOSE, &pts[8], 2, 0.f, user_data);
}
static GskContour *
gsk_circle_contour_reverse (const GskContour *contour)
{
const GskCircleContour *self = (const GskCircleContour *) contour;
GskCircleContour *copy;
copy = g_new0 (GskCircleContour, 1);
gsk_circle_contour_copy (contour, (GskContour *)copy);
copy->ccw = !self->ccw;
return (GskContour *)copy;
}
static int
gsk_circle_contour_get_winding (const GskContour *contour,
const graphene_point_t *point)
{
const GskCircleContour *self = (const GskCircleContour *) contour;
if (graphene_point_distance (point, &self->center, NULL, NULL) <= self->radius)
return self->ccw ? -1 : 1;
return 0;
}
static gsize
gsk_circle_contour_get_n_ops (const GskContour *contour)
{
const GskCircleContour *self = (const GskCircleContour *) contour;
/* idx == 0 is the move (which does not really exist here,
* but gskpath.c assumes there is one).
*/
return self->radius > 0 ? 6 : 2;
}
static gboolean
gsk_circle_contour_get_closest_point (const GskContour *contour,
const graphene_point_t *point,
float threshold,
GskPathPoint *result,
float *out_dist)
{
const GskCircleContour *self = (const GskCircleContour *) contour;
float dist, angle, t;
gsize idx;
dist = fabsf (graphene_point_distance (&self->center, point, NULL, NULL) - self->radius);
if (dist > threshold)
return FALSE;
angle = atan2f (point->y - self->center.y, point->x - self->center.x);
if (angle < 0)
angle = 2 * M_PI + angle;
t = CLAMP (angle / (2 * M_PI), 0, 1);
if (self->ccw)
t = 1 - t;
t = t * 4;
idx = 1;
do {
if (t < 1)
break;
t = t - 1;
idx = idx + 1;
} while (t != 0);
result->idx = idx;
result->t = t;
return TRUE;
}
static void
gsk_circle_contour_get_position (const GskContour *contour,
const GskPathPoint *point,
graphene_point_t *position)
{
const GskCircleContour *self = (const GskCircleContour *) contour;
gsize idx = point->idx;
float t = point->t;
if (self->radius == 0)
{
*position = self->center;
return;
}
/* avoid the z */
if (idx == 5)
{
idx = 4;
t = 1;
}
if (self->ccw)
{
idx = 5 - idx;
t = 1 - t;
}
if ((idx == 1 && t == 0) || (idx == 4 && t == 1))
{
*position = GRAPHENE_POINT_INIT (self->center.x + self->radius, self->center.y);
}
else
{
float s, c;
_sincosf (M_PI_2 * ((idx - 1) + t), &s, &c);
*position = GRAPHENE_POINT_INIT (self->center.x + c * self->radius,
self->center.y + s * self->radius);
}
}
static void
gsk_circle_contour_get_tangent (const GskContour *contour,
const GskPathPoint *point,
GskPathDirection direction,
graphene_vec2_t *tangent)
{
const GskCircleContour *self = (const GskCircleContour *) contour;
graphene_point_t p;
gsk_circle_contour_get_position (contour, point, &p);
graphene_vec2_init (tangent, - p.y + self->center.y, p.x - self->center.x);
graphene_vec2_normalize (tangent, tangent);
}
static float
gsk_circle_contour_get_curvature (const GskContour *contour,
const GskPathPoint *point,
GskPathDirection direction,
graphene_point_t *center)
{
const GskCircleContour *self = (const GskCircleContour *) contour;
if (center)
*center = self->center;
if (self->radius == 0)
return INFINITY;
return 1.f / self->radius;
}
static void
gsk_circle_contour_add_segment (const GskContour *contour,
GskPathBuilder *builder,
gboolean emit_move_to,
const GskPathPoint *start,
const GskPathPoint *end)
{
GskPath *path;
const GskContour *std;
path = convert_to_standard_contour (contour);
std = gsk_path_get_contour (path, 0);
gsk_standard_contour_add_segment (std, builder, emit_move_to, start, end);
gsk_path_unref (path);
}
static gpointer
gsk_circle_contour_init_measure (const GskContour *contour,
float tolerance,
float *out_length)
{
const GskCircleContour *self = (const GskCircleContour *) contour;
*out_length = 2 * M_PI * self->radius;
return NULL;
}
static void
gsk_circle_contour_free_measure (const GskContour *contour,
gpointer data)
{
}
static void
gsk_circle_contour_get_point (const GskContour *contour,
gpointer measure_data,
float distance,
GskPathPoint *result)
{
const GskCircleContour *self = (const GskCircleContour *) contour;
float t;
gsize idx;
if (self->radius == 0)
{
result->idx = 1;
result->t = 0;
return;
}
t = distance / (M_PI_2 * self->radius);
idx = 1;
do {
if (t < 1)
break;
t = t - 1;
idx = idx + 1;
} while (t > 0);
if (self->ccw)
{
idx = 5 - idx;
t = 1 - t;
}
result->idx = idx;
result->t = t;
}
static float
gsk_circle_contour_get_distance (const GskContour *contour,
const GskPathPoint *point,
gpointer measure_data)
{
const GskCircleContour *self = (const GskCircleContour *) contour;
float t;
gsize idx;
if (self->radius == 0)
return 0;
idx = point->idx;
t = point->t;
if (self->ccw)
{
idx = 5 - idx;
t = 1 - t;
}
return M_PI_2 * self->radius * (idx - 1 + t);
}
static const GskContourClass GSK_CIRCLE_CONTOUR_CLASS =
{
sizeof (GskCircleContour),
"GskCircleContour",
gsk_circle_contour_copy,
gsk_contour_get_size_default,
gsk_circle_contour_get_flags,
gsk_circle_contour_print,
gsk_circle_contour_get_bounds,
gsk_circle_contour_get_stroke_bounds,
gsk_circle_contour_foreach,
gsk_circle_contour_reverse,
gsk_circle_contour_get_winding,
gsk_circle_contour_get_n_ops,
gsk_circle_contour_get_closest_point,
gsk_circle_contour_get_position,
gsk_circle_contour_get_tangent,
gsk_circle_contour_get_curvature,
gsk_circle_contour_add_segment,
gsk_circle_contour_init_measure,
gsk_circle_contour_free_measure,
gsk_circle_contour_get_point,
gsk_circle_contour_get_distance,
};
GskContour *
gsk_circle_contour_new (const graphene_point_t *center,
float radius)
{
GskCircleContour *self;
g_assert (radius >= 0);
self = g_new0 (GskCircleContour, 1);
self->contour.klass = &GSK_CIRCLE_CONTOUR_CLASS;
self->contour.klass = &GSK_CIRCLE_CONTOUR_CLASS;
self->center = *center;
self->radius = radius;
self->ccw = FALSE;
return (GskContour *) self;
}
/* }}} */
/* {{{ Rectangle */
typedef struct _GskRectContour GskRectContour;
struct _GskRectContour
{
GskContour contour;
float x;
float y;
float width;
float height;
gsize n_ops;
};
static void
gsk_rect_contour_copy (const GskContour *contour,
GskContour *dest)
{
const GskRectContour *self = (const GskRectContour *) contour;
GskRectContour *target = (GskRectContour *) dest;
*target = *self;
}
static GskPathFlags
gsk_rect_contour_get_flags (const GskContour *contour)
{
return GSK_PATH_FLAT | GSK_PATH_CLOSED;
}
static void
gsk_rect_contour_print (const GskContour *contour,
GString *string)
{
const GskRectContour *self = (const GskRectContour *) contour;
_g_string_append_point (string, "M ", &GRAPHENE_POINT_INIT (self->x, self->y));
_g_string_append_float (string, " h ", self->width);
_g_string_append_float (string, " v ", self->height);
_g_string_append_float (string, " h ", - self->width);
g_string_append (string, " z");
}
static gboolean
gsk_rect_contour_get_bounds (const GskContour *contour,
GskBoundingBox *bounds)
{
const GskRectContour *self = (const GskRectContour *) contour;
gsk_bounding_box_init (bounds,
&GRAPHENE_POINT_INIT (self->x, self->y),
&GRAPHENE_POINT_INIT (self->x + self->width, self->y + self->height));
return TRUE;
}
static gboolean
gsk_rect_contour_get_stroke_bounds (const GskContour *contour,
const GskStroke *stroke,
GskBoundingBox *bounds)
{
const GskRectContour *self = (const GskRectContour *) contour;
graphene_rect_t rect;
graphene_rect_init (&rect, self->x, self->y, self->width, self->height);
graphene_rect_inset (&rect, - stroke->line_width, - stroke->line_width);
gsk_bounding_box_init_from_rect (bounds, &rect);
return TRUE;
}
static gboolean
gsk_rect_contour_foreach (const GskContour *contour,
GskPathForeachFunc func,
gpointer user_data)
{
const GskRectContour *self = (const GskRectContour *) contour;
graphene_point_t pts[] = {
GRAPHENE_POINT_INIT (self->x, self->y),
GRAPHENE_POINT_INIT (self->x + self->width, self->y),
GRAPHENE_POINT_INIT (self->x + self->width, self->y + self->height),
GRAPHENE_POINT_INIT (self->x, self->y + self->height),
GRAPHENE_POINT_INIT (self->x, self->y)
};
return func (GSK_PATH_MOVE, &pts[0], 1, 0.f, user_data) &&
maybe_emit_line (&pts[0], func, user_data) &&
maybe_emit_line (&pts[1], func, user_data) &&
maybe_emit_line (&pts[2], func, user_data) &&
func (GSK_PATH_CLOSE, &pts[3], 2, 0.f, user_data);
}
static GskContour *
gsk_rect_contour_reverse (const GskContour *contour)
{
const GskRectContour *self = (const GskRectContour *) contour;
return gsk_rect_contour_new (&GRAPHENE_RECT_INIT (self->x + self->width,
self->y,
- self->width,
self->height));
}
static int
gsk_rect_contour_get_winding (const GskContour *contour,
const graphene_point_t *point)
{
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))
{
if ((self->width < 0) != (self->height < 0))
return -1;
else
return 1;
}
return 0;
}
static gsize
gsk_rect_contour_get_n_ops (const GskContour *contour)
{
const GskRectContour *self = (const GskRectContour *) contour;
return self->n_ops;
}
static gboolean
gsk_rect_contour_get_closest_point (const GskContour *contour,
const graphene_point_t *point,
float threshold,
GskPathPoint *result,
float *out_dist)
{
return contour_get_closest_point (contour, point, threshold, result, out_dist);
}
static void
gsk_rect_contour_get_position (const GskContour *contour,
const GskPathPoint *point,
graphene_point_t *position)
{
GskCurve curve;
contour_init_curve (contour, point->idx, &curve);
gsk_curve_get_point (&curve, point->t, position);
}
static void
gsk_rect_contour_get_tangent (const GskContour *contour,
const GskPathPoint *point,
GskPathDirection direction,
graphene_vec2_t *tangent)
{
const GskRectContour *self = (const GskRectContour *) contour;
gsize idx = point->idx;
float t = point->t;
GskCurve curve;
apply_corner_direction (direction, &idx, &t, self->n_ops);
contour_init_curve (contour, idx, &curve);
gsk_curve_get_tangent (&curve, t, tangent);
if (direction == GSK_PATH_TO_START || direction == GSK_PATH_FROM_END)
graphene_vec2_negate (tangent, tangent);
}
static float
gsk_rect_contour_get_curvature (const GskContour *contour,
const GskPathPoint *point,
GskPathDirection direction,
graphene_point_t *center)
{
return 0;
}
static void
gsk_rect_contour_add_segment (const GskContour *contour,
GskPathBuilder *builder,
gboolean emit_move_to,
const GskPathPoint *start,
const GskPathPoint *end)
{
contour_add_segment (contour, builder, emit_move_to, start, end);
}
static gpointer
gsk_rect_contour_init_measure (const GskContour *contour,
float tolerance,
float *out_length)
{
const GskRectContour *self = (const GskRectContour *) contour;
*out_length = 2 * (fabsf (self->width) + fabsf (self->height));
return NULL;
}
static void
gsk_rect_contour_free_measure (const GskContour *contour,
gpointer data)
{
}
static inline int
rect_contour_get_sides (const GskRectContour *self,
float sides[5])
{
int n_sides = 0;
sides[n_sides++] = 0;
if (self->width != 0)
sides[n_sides++] = fabsf (self->width);
if (self->height != 0)
sides[n_sides++] = fabsf (self->height);
if (self->width != 0)
sides[n_sides++] = fabsf (self->width);
sides[n_sides++] = fabsf (self->height);
return n_sides;
}
static void
gsk_rect_contour_get_point (const GskContour *contour,
gpointer measure_data,
float distance,
GskPathPoint *result)
{
const GskRectContour *self = (const GskRectContour *) contour;
float sides[5];
int n_sides = 0;
if (distance == 0)
{
result->idx = 1;
result->t = 0;
return;
}
n_sides = rect_contour_get_sides (self, sides);
for (int i = 0; i < n_sides; i++)
{
if (distance <= sides[i])
{
result->idx = i;
result->t = distance / sides[i];
return;
}
distance -= sides[i];
}
result->idx = n_sides - 1;
result->t = 1;
}
static float
gsk_rect_contour_get_distance (const GskContour *contour,
const GskPathPoint *point,
gpointer measure_data)
{
const GskRectContour *self = (const GskRectContour *) contour;
float sides[5];
int n_sides G_GNUC_UNUSED;
float distance;
n_sides = rect_contour_get_sides (self, sides);
g_assert (point->idx < n_sides);
distance = 0;
for (int i = 0; i < point->idx; i++)
distance += sides[i];
distance += point->t * sides[point->idx];
return distance;
}
static const GskContourClass GSK_RECT_CONTOUR_CLASS =
{
sizeof (GskRectContour),
"GskRectContour",
gsk_rect_contour_copy,
gsk_contour_get_size_default,
gsk_rect_contour_get_flags,
gsk_rect_contour_print,
gsk_rect_contour_get_bounds,
gsk_rect_contour_get_stroke_bounds,
gsk_rect_contour_foreach,
gsk_rect_contour_reverse,
gsk_rect_contour_get_winding,
gsk_rect_contour_get_n_ops,
gsk_rect_contour_get_closest_point,
gsk_rect_contour_get_position,
gsk_rect_contour_get_tangent,
gsk_rect_contour_get_curvature,
gsk_rect_contour_add_segment,
gsk_rect_contour_init_measure,
gsk_rect_contour_free_measure,
gsk_rect_contour_get_point,
gsk_rect_contour_get_distance,
};
GskContour *
gsk_rect_contour_new (const graphene_rect_t *rect)
{
GskRectContour *self;
gsize n_ops[] = { 2, 3, 5 };
self = g_new0 (GskRectContour, 1);
self->contour.klass = &GSK_RECT_CONTOUR_CLASS;
self->x = rect->origin.x;
self->y = rect->origin.y;
self->width = rect->size.width;
self->height = rect->size.height;
self->n_ops = n_ops[(self->width != 0) + (self->height != 0)];
return (GskContour *) self;
}
/* }}} */
/* {{{ Rounded Rectangle */
typedef struct _GskRoundedRectContour GskRoundedRectContour;
struct _GskRoundedRectContour
{
GskContour contour;
GskRoundedRect rect;
gboolean ccw;
gsize n_ops;
};
static void
gsk_rounded_rect_contour_copy (const GskContour *contour,
GskContour *dest)
{
const GskRoundedRectContour *self = (const GskRoundedRectContour *) contour;
GskRoundedRectContour *target = (GskRoundedRectContour *) dest;
*target = *self;
}
static GskPathFlags
gsk_rounded_rect_contour_get_flags (const GskContour *contour)
{
return GSK_PATH_CLOSED;
}
static gboolean
gsk_rounded_rect_contour_get_bounds (const GskContour *contour,
GskBoundingBox *bounds)
{
const GskRoundedRectContour *self = (const GskRoundedRectContour *) contour;
gsk_bounding_box_init_from_rect (bounds, &self->rect.bounds);
return TRUE;
}
static gboolean
gsk_rounded_rect_contour_get_stroke_bounds (const GskContour *contour,
const GskStroke *stroke,
GskBoundingBox *bounds)
{
const GskRoundedRectContour *self = (const GskRoundedRectContour *) contour;
GskBoundingBox b;
gsk_bounding_box_init_from_rect (&b, &self->rect.bounds);
gsk_bounding_box_init (bounds,
&GRAPHENE_POINT_INIT (b.min.x - stroke->line_width,
b.min.y - stroke->line_width),
&GRAPHENE_POINT_INIT (b.max.x + stroke->line_width,
b.max.y + stroke->line_width));
return TRUE;
}
static void
get_rounded_rect_points (const GskRoundedRect *rect,
graphene_point_t *pts)
{
pts[0] = GRAPHENE_POINT_INIT (rect->bounds.origin.x + rect->corner[GSK_CORNER_TOP_LEFT].width, rect->bounds.origin.y);
pts[1] = GRAPHENE_POINT_INIT (rect->bounds.origin.x + rect->bounds.size.width - rect->corner[GSK_CORNER_TOP_RIGHT].width, rect->bounds.origin.y);
pts[2] = GRAPHENE_POINT_INIT (rect->bounds.origin.x + rect->bounds.size.width, rect->bounds.origin.y);
pts[3] = GRAPHENE_POINT_INIT (rect->bounds.origin.x + rect->bounds.size.width, rect->bounds.origin.y + rect->corner[GSK_CORNER_TOP_RIGHT].height);
pts[4] = GRAPHENE_POINT_INIT (rect->bounds.origin.x + rect->bounds.size.width, rect->bounds.origin.y + rect->bounds.size.height - rect->corner[GSK_CORNER_BOTTOM_RIGHT].height);
pts[5] = GRAPHENE_POINT_INIT (rect->bounds.origin.x + rect->bounds.size.width, rect->bounds.origin.y + rect->bounds.size.height);
pts[6] = GRAPHENE_POINT_INIT (rect->bounds.origin.x + rect->bounds.size.width - rect->corner[GSK_CORNER_BOTTOM_RIGHT].width, rect->bounds.origin.y + rect->bounds.size.height);
pts[7] = GRAPHENE_POINT_INIT (rect->bounds.origin.x + rect->corner[GSK_CORNER_BOTTOM_LEFT].width, rect->bounds.origin.y + rect->bounds.size.height);
pts[8] = GRAPHENE_POINT_INIT (rect->bounds.origin.x, rect->bounds.origin.y + rect->bounds.size.height);
pts[9] = GRAPHENE_POINT_INIT (rect->bounds.origin.x, rect->bounds.origin.y + rect->bounds.size.height - rect->corner[GSK_CORNER_BOTTOM_LEFT].height);
pts[10] = GRAPHENE_POINT_INIT (rect->bounds.origin.x, rect->bounds.origin.y + rect->corner[GSK_CORNER_TOP_LEFT].height);
pts[11] = GRAPHENE_POINT_INIT (rect->bounds.origin.x, rect->bounds.origin.y);
pts[12] = GRAPHENE_POINT_INIT (rect->bounds.origin.x + rect->corner[GSK_CORNER_TOP_LEFT].width, rect->bounds.origin.y);
pts[13] = GRAPHENE_POINT_INIT (rect->bounds.origin.x + rect->corner[GSK_CORNER_TOP_LEFT].width, rect->bounds.origin.y);
}
static gboolean
gsk_rounded_rect_contour_foreach (const GskContour *contour,
GskPathForeachFunc func,
gpointer user_data)
{
const GskRoundedRectContour *self = (const GskRoundedRectContour *) contour;
graphene_point_t pts[14];
get_rounded_rect_points (&self->rect, pts);
if (self->ccw)
{
graphene_point_t p;
#define SWAP(a,b,c) a = b; b = c; c = a;
SWAP (p, pts[1], pts[11]);
SWAP (p, pts[2], pts[10]);
SWAP (p, pts[3], pts[9]);
SWAP (p, pts[4], pts[8]);
SWAP (p, pts[5], pts[7]);
#undef SWAP
return func (GSK_PATH_MOVE, &pts[0], 1, 0.f, user_data) &&
maybe_emit_conic (&pts[0], M_SQRT1_2, func, user_data) &&
maybe_emit_line (&pts[2], func, user_data) &&
maybe_emit_conic (&pts[3], M_SQRT1_2, func, user_data) &&
maybe_emit_line (&pts[5], func, user_data) &&
maybe_emit_conic (&pts[6], M_SQRT1_2, func, user_data) &&
maybe_emit_line (&pts[8], func, user_data) &&
maybe_emit_conic (&pts[9], M_SQRT1_2, func, user_data) &&
maybe_emit_line (&pts[11], func, user_data) &&
func (GSK_PATH_CLOSE, &pts[12], 2, 0.f, user_data);
}
else
{
return func (GSK_PATH_MOVE, &pts[0], 1, 0.f, user_data) &&
maybe_emit_line (&pts[0], func, user_data) &&
maybe_emit_conic (&pts[1], M_SQRT1_2, func, user_data) &&
maybe_emit_line (&pts[3], func, user_data) &&
maybe_emit_conic (&pts[4], M_SQRT1_2, func, user_data) &&
maybe_emit_line (&pts[6], func, user_data) &&
maybe_emit_conic (&pts[7], M_SQRT1_2, func, user_data) &&
maybe_emit_line (&pts[9], func, user_data) &&
maybe_emit_conic (&pts[10], M_SQRT1_2, func, user_data) &&
func (GSK_PATH_CLOSE, &pts[12], 2, 0.f, user_data);
}
}
static GskContour *
gsk_rounded_rect_contour_reverse (const GskContour *contour)
{
const GskRoundedRectContour *self = (const GskRoundedRectContour *) contour;
GskRoundedRectContour *copy;
copy = g_new0 (GskRoundedRectContour, 1);
gsk_rounded_rect_contour_copy (contour, (GskContour *)copy);
copy->ccw = !self->ccw;
return (GskContour *)copy;
}
static int
gsk_rounded_rect_contour_get_winding (const GskContour *contour,
const graphene_point_t *point)
{
const GskRoundedRectContour *self = (const GskRoundedRectContour *) contour;
if (gsk_rounded_rect_contains_point (&self->rect, point))
return self->ccw ? -1 : 1;
return 0;
}
static gsize
gsk_rounded_rect_contour_get_n_ops (const GskContour *contour)
{
const GskRoundedRectContour *self = (const GskRoundedRectContour *) contour;
return self->n_ops;
}
static gboolean
gsk_rounded_rect_contour_get_closest_point (const GskContour *contour,
const graphene_point_t *point,
float threshold,
GskPathPoint *result,
float *out_dist)
{
return contour_get_closest_point (contour, point, threshold, result, out_dist);
}
static void
gsk_rounded_rect_contour_get_position (const GskContour *contour,
const GskPathPoint *point,
graphene_point_t *position)
{
GskCurve curve;
contour_init_curve (contour, point->idx, &curve);
gsk_curve_get_point (&curve, point->t, position);
}
static void
gsk_rounded_rect_contour_get_tangent (const GskContour *contour,
const GskPathPoint *point,
GskPathDirection direction,
graphene_vec2_t *tangent)
{
const GskRoundedRectContour *self = (const GskRoundedRectContour *) contour;
gsize idx = point->idx;
float t = point->t;
GskCurve curve;
/* Avoid the z, since it has length 0 and won't give us a tangent */
if (idx == self->n_ops - 1)
{
idx = self->n_ops - 2;
t = 1;
}
apply_corner_direction (direction, &idx, &t, self->n_ops - 1);
contour_init_curve (contour, idx, &curve);
gsk_curve_get_tangent (&curve, t, tangent);
if (direction == GSK_PATH_TO_START || direction == GSK_PATH_FROM_END)
graphene_vec2_negate (tangent, tangent);
}
static float
gsk_rounded_rect_contour_get_curvature (const GskContour *contour,
const GskPathPoint *point,
GskPathDirection direction,
graphene_point_t *center)
{
const GskRoundedRectContour *self = (const GskRoundedRectContour *) contour;
GskCurve curve;
gsize idx = point->idx;
float t = point->t;
/* Avoid the z, since it has length 0 and won't give us curvature */
if (idx == self->n_ops - 1)
{
idx = self->n_ops - 2;
t = 1;
}
apply_corner_direction (direction, &idx, &t, self->n_ops - 1);
contour_init_curve (contour, idx, &curve);
return gsk_curve_get_curvature (&curve, t, center);
}
static void
gsk_rounded_rect_contour_add_segment (const GskContour *contour,
GskPathBuilder *builder,
gboolean emit_move_to,
const GskPathPoint *start,
const GskPathPoint *end)
{
contour_add_segment (contour, builder, emit_move_to, start, end);
}
typedef struct
{
const GskContour *contour;
gpointer measure_data;
} RoundedRectMeasureData;
static gpointer
gsk_rounded_rect_contour_init_measure (const GskContour *contour,
float tolerance,
float *out_length)
{
RoundedRectMeasureData *data;
GskPath *path;
path = convert_to_standard_contour (contour);
data = g_new (RoundedRectMeasureData, 1);
data->contour = gsk_contour_dup (gsk_path_get_contour (path, 0));
data->measure_data = gsk_standard_contour_init_measure (data->contour, tolerance, out_length);
gsk_path_unref (path);
return data;
}
static void
gsk_rounded_rect_contour_free_measure (const GskContour *contour,
gpointer measure_data)
{
RoundedRectMeasureData *data = measure_data;
gsk_standard_contour_free_measure (data->contour, data->measure_data);
g_free (data);
}
static void
gsk_rounded_rect_contour_get_point (const GskContour *contour,
gpointer measure_data,
float distance,
GskPathPoint *result)
{
RoundedRectMeasureData *data = measure_data;
gsk_standard_contour_get_point (data->contour, data->measure_data, distance, result);
}
static float
gsk_rounded_rect_contour_get_distance (const GskContour *contour,
const GskPathPoint *point,
gpointer measure_data)
{
RoundedRectMeasureData *data = measure_data;
return gsk_standard_contour_get_distance (data->contour, point, data->measure_data);
}
static const GskContourClass GSK_ROUNDED_RECT_CONTOUR_CLASS =
{
sizeof (GskRoundedRectContour),
"GskRoundedRectContour",
gsk_rounded_rect_contour_copy,
gsk_contour_get_size_default,
gsk_rounded_rect_contour_get_flags,
gsk_contour_print_default,
gsk_rounded_rect_contour_get_bounds,
gsk_rounded_rect_contour_get_stroke_bounds,
gsk_rounded_rect_contour_foreach,
gsk_rounded_rect_contour_reverse,
gsk_rounded_rect_contour_get_winding,
gsk_rounded_rect_contour_get_n_ops,
gsk_rounded_rect_contour_get_closest_point,
gsk_rounded_rect_contour_get_position,
gsk_rounded_rect_contour_get_tangent,
gsk_rounded_rect_contour_get_curvature,
gsk_rounded_rect_contour_add_segment,
gsk_rounded_rect_contour_init_measure,
gsk_rounded_rect_contour_free_measure,
gsk_rounded_rect_contour_get_point,
gsk_rounded_rect_contour_get_distance,
};
static gsize
rounded_rect_compute_n_ops (const GskRoundedRect *rect)
{
graphene_point_t pts[14];
gsize n_ops;
get_rounded_rect_points (rect, pts);
n_ops = 2;
if (!graphene_point_equal (&pts[0], &pts[1]))
n_ops++;
if (!graphene_point_equal (&pts[1], &pts[2]) ||
!graphene_point_equal (&pts[2], &pts[3]))
n_ops++;
if (!graphene_point_equal (&pts[3], &pts[4]))
n_ops++;
if (!graphene_point_equal (&pts[4], &pts[5]) ||
!graphene_point_equal (&pts[5], &pts[6]))
n_ops++;
if (!graphene_point_equal (&pts[6], &pts[7]))
n_ops++;
if (!graphene_point_equal (&pts[7], &pts[8]) ||
!graphene_point_equal (&pts[8], &pts[9]))
n_ops++;
if (!graphene_point_equal (&pts[9], &pts[10]))
n_ops++;
if (!graphene_point_equal (&pts[10], &pts[11]) ||
!graphene_point_equal (&pts[11], &pts[12]))
n_ops++;
return n_ops;
}
GskContour *
gsk_rounded_rect_contour_new (const GskRoundedRect *rect)
{
GskRoundedRectContour *self;
self = g_new0 (GskRoundedRectContour, 1);
self->contour.klass = &GSK_ROUNDED_RECT_CONTOUR_CLASS;
self->rect = *rect;
gsk_rounded_rect_normalize (&self->rect);
self->n_ops = rounded_rect_compute_n_ops (&self->rect);
return (GskContour *) self;
}
/* }}} */
/* {{{ API */
const char *
gsk_contour_get_type_name (const GskContour *self)
{
return self->klass->type_name;
}
gsize
gsk_contour_get_size (const GskContour *self)
{
return self->klass->get_size (self);
}
void
gsk_contour_copy (GskContour *dest,
const GskContour *src)
{
src->klass->copy (src, dest);
}
GskContour *
gsk_contour_dup (const GskContour *src)
{
GskContour *copy;
copy = g_malloc0 (gsk_contour_get_size (src));
gsk_contour_copy (copy, src);
return copy;
}
GskContour *
gsk_contour_reverse (const GskContour *src)
{
return src->klass->reverse (src);
}
GskPathFlags
gsk_contour_get_flags (const GskContour *self)
{
return self->klass->get_flags (self);
}
void
gsk_contour_print (const GskContour *self,
GString *string)
{
self->klass->print (self, string);
}
gboolean
gsk_contour_get_bounds (const GskContour *self,
GskBoundingBox *bounds)
{
return self->klass->get_bounds (self, bounds);
}
gboolean
gsk_contour_get_stroke_bounds (const GskContour *self,
const GskStroke *stroke,
GskBoundingBox *bounds)
{
return self->klass->get_stroke_bounds (self, stroke, bounds);
}
gboolean
gsk_contour_foreach (const GskContour *self,
GskPathForeachFunc func,
gpointer user_data)
{
return self->klass->foreach (self, func, user_data);
}
int
gsk_contour_get_winding (const GskContour *self,
const graphene_point_t *point)
{
return self->klass->get_winding (self, point);
}
gboolean
gsk_contour_get_closest_point (const GskContour *self,
const graphene_point_t *point,
float threshold,
GskPathPoint *result,
float *out_dist)
{
return self->klass->get_closest_point (self, point, threshold, result, out_dist);
}
/* Not related to how many curves foreach produces.
*
* GskPath assumes that the start- and endpoints
* of a contour are { x, 1, 0 } and { x, n_ops - 1, 1 }.
*
* While the standard and rounded rect contours use
* one point per op, the circle contour uses a single
* 'segment' in path points, with a t that ranges
* from 0 to 1 to cover the angles from 0 to 360 (or
* 360 to 0 in the ccw case).
*/
gsize
gsk_contour_get_n_ops (const GskContour *self)
{
return self->klass->get_n_ops (self);
}
void
gsk_contour_get_position (const GskContour *self,
const GskPathPoint *point,
graphene_point_t *pos)
{
self->klass->get_position (self, point, pos);
}
void
gsk_contour_get_tangent (const GskContour *self,
const GskPathPoint *point,
GskPathDirection direction,
graphene_vec2_t *tangent)
{
self->klass->get_tangent (self, point, direction, tangent);
}
float
gsk_contour_get_curvature (const GskContour *self,
const GskPathPoint *point,
GskPathDirection direction,
graphene_point_t *center)
{
return self->klass->get_curvature (self, point, direction, center);
}
void
gsk_contour_add_segment (const GskContour *self,
GskPathBuilder *builder,
gboolean emit_move_to,
const GskPathPoint *start,
const GskPathPoint *end)
{
self->klass->add_segment (self, builder, emit_move_to, start, end);
}
gpointer
gsk_contour_init_measure (const GskContour *self,
float tolerance,
float *out_length)
{
return self->klass->init_measure (self, tolerance, out_length);
}
void
gsk_contour_free_measure (const GskContour *self,
gpointer data)
{
self->klass->free_measure (self, data);
}
void
gsk_contour_get_point (const GskContour *self,
gpointer measure_data,
float distance,
GskPathPoint *result)
{
self->klass->get_point (self, measure_data, distance, result);
}
float
gsk_contour_get_distance (const GskContour *self,
const GskPathPoint *point,
gpointer measure_data)
{
return self->klass->get_distance (self, point, measure_data);
}
/* }}} */
/* vim:set foldmethod=marker expandtab: */