graphene-quad.c 6.13 KB
Newer Older
Iñigo Martínez's avatar
Iñigo Martínez committed
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219
/* graphene-quad.c: Quad
 *
 * Copyright 2014  Emmanuele Bassi
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */

/**
 * SECTION:graphene-quad
 * @title: Quad
 * @short_description: Four-vertex quadrilateral
 *
 * A #graphene_quad_t represents a coplanar, four vertex quadrilateral shape.
 */

#include "graphene-private.h"

#include "graphene-quad.h"

#include "graphene-line-segment-private.h"
#include "graphene-rect.h"
#include "graphene-simd4f.h"

#include <string.h>

/**
 * graphene_quad_alloc: (constructor)
 *
 * Allocates a new #graphene_quad_t instance.
 *
 * The contents of the returned instance are undefined.
 *
 * Returns: (transfer full): the newly created #graphene_quad_t instance
 *
 * Since: 1.0
 */
graphene_quad_t *
graphene_quad_alloc (void)
{
  return calloc (1, sizeof (graphene_quad_t));
}

/**
 * graphene_quad_free:
 * @q: a #graphene_quad_t
 *
 * Frees the resources allocated by graphene_quad_alloc()
 *
 * Since: 1.0
 */
void
graphene_quad_free (graphene_quad_t *q)
{
  free (q);
}

/**
 * graphene_quad_init:
 * @q: the #graphene_quad_t to initialize
 * @p1: the first point of the quadrilateral
 * @p2: the second point of the quadrilateral
 * @p3: the third point of the quadrilateral
 * @p4: the fourth point of the quadrilateral
 *
 * Initializes a #graphene_quad_t with the given points.
 *
 * Returns: (transfer none): the initialized #graphene_quad_t
 *
 * Since: 1.0
 */
graphene_quad_t *
graphene_quad_init (graphene_quad_t        *q,
                    const graphene_point_t *p1,
                    const graphene_point_t *p2,
                    const graphene_point_t *p3,
                    const graphene_point_t *p4)
{
  q->points[0] = *p1;
  q->points[1] = *p2;
  q->points[2] = *p3;
  q->points[3] = *p4;

  return q;
}

/**
 * graphene_quad_init_from_rect:
 * @q: the #graphene_quad_t to initialize
 * @r: a #graphene_rect_t
 *
 * Initializes a #graphene_quad_t using the four corners of the
 * given #graphene_rect_t.
 *
 * Returns: (transfer none): the initialized #graphene_quad_t
 *
 * Since: 1.0
 */
graphene_quad_t *
graphene_quad_init_from_rect (graphene_quad_t       *q,
                              const graphene_rect_t *r)
{
  graphene_rect_get_top_left (r, &(q->points[0]));
  graphene_rect_get_top_right (r, &(q->points[1]));
  graphene_rect_get_bottom_right (r, &(q->points[2]));
  graphene_rect_get_bottom_left (r, &(q->points[3]));

  return q;
}

/**
 * graphene_quad_init_from_points:
 * @q: the #graphene_quad_t to initialize
 * @points: (array fixed-size=4): an array of 4 #graphene_point_t
 *
 * Initializes a #graphene_quad_t using an array of points.
 *
 * Returns: (transfer none): the initialized #graphene_quad_t
 *
 * Since: 1.2
 */
graphene_quad_t *
graphene_quad_init_from_points (graphene_quad_t        *q,
                                const graphene_point_t  points[])
{
  memcpy (q->points, points, sizeof (graphene_point_t) * 4);

  return q;
}

/**
 * graphene_quad_contains:
 * @q: a #graphene_quad_t
 * @p: a #graphene_point_t
 *
 * Checks if the given #graphene_quad_t contains the given #graphene_point_t.
 *
 * Returns: `true` if the point is inside the #graphene_quad_t
 *
 * Since: 1.0
 */
bool
graphene_quad_contains (const graphene_quad_t  *q,
                        const graphene_point_t *p)
{
  graphene_line_segment_t l1, l2, l3, l4;

  l1 = graphene_line_segment_init (&q->points[0], &q->points[1]);
  l2 = graphene_line_segment_init (&q->points[1], &q->points[2]);
  l3 = graphene_line_segment_init (&q->points[2], &q->points[3]);
  l4 = graphene_line_segment_init (&q->points[3], &q->points[0]);

  return graphene_line_segment_points_on_same_side (l1, p, &(q->points[2])) &&
         graphene_line_segment_points_on_same_side (l2, p, &(q->points[3])) &&
         graphene_line_segment_points_on_same_side (l3, p, &(q->points[0])) &&
         graphene_line_segment_points_on_same_side (l4, p, &(q->points[1]));
}

/**
 * graphene_quad_bounds:
 * @q: a #graphene_quad_t
 * @r: (out caller-allocates): return location for a #graphene_rect_t
 *
 * Computes the bounding rectangle of @q and places it into @r.
 *
 * Since: 1.0
 */
void
graphene_quad_bounds (const graphene_quad_t *q,
                      graphene_rect_t       *r)
{
  graphene_simd4f_t vx, vy;
  float min_x, max_x;
  float min_y, max_y;

  vx = graphene_simd4f_init (q->points[0].x, q->points[1].x, q->points[2].x, q->points[3].x);
  vy = graphene_simd4f_init (q->points[0].y, q->points[1].y, q->points[2].y, q->points[3].y);

  min_x = graphene_simd4f_get_x (graphene_simd4f_min_val (vx));
  min_y = graphene_simd4f_get_x (graphene_simd4f_min_val (vy));

  max_x = graphene_simd4f_get_x (graphene_simd4f_max_val (vx));
  max_y = graphene_simd4f_get_x (graphene_simd4f_max_val (vy));

  graphene_rect_init (r, min_x, min_y, max_x - min_x, max_y - min_y);
}

/**
 * graphene_quad_get_point:
 * @q: a #graphene_quad_t
 * @index_: the index of the point to retrieve
 *
 * Retrieves the point of a #graphene_quad_t at the given index.
 *
 * Returns: (transfer none): a #graphene_point_t
 *
 * Since: 1.0
 */
const graphene_point_t *
graphene_quad_get_point (const graphene_quad_t *q,
                         unsigned int           index_)
{
  return &q->points[index_];
}