tests/vertex-clip-test.c

   1 /*
   2  * Copyright © 2013 Sam Spilsbury <smspillaz@gmail.com>
   3  *
   4  * Permission to use, copy, modify, distribute, and sell this software and
   5  * its documentation for any purpose is hereby granted without fee, provided
   6  * that the above copyright notice appear in all copies and that both that
   7  * copyright notice and this permission notice appear in supporting
   8  * documentation, and that the name of the copyright holders not be used in
   9  * advertising or publicity pertaining to distribution of the software
  10  * without specific, written prior permission.  The copyright holders make
  11  * no representations about the suitability of this software for any
  12  * purpose.  It is provided "as is" without express or implied warranty.
  13  *
  14  * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS
  15  * SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
  16  * FITNESS, IN NO EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY
  17  * SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER
  18  * RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF
  19  * CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
  20  * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  21  */
  22 #include <assert.h>
  23 #include <stdio.h>
  24 #include <stdlib.h>
  25 #include <string.h>
  26 #include <math.h>
  27
  28 #include "weston-test-runner.h"
  29
  30 #include "../src/vertex-clipping.h"
  31
  32 #define BOUNDING_BOX_TOP_Y 100.0f
  33 #define BOUNDING_BOX_LEFT_X 50.0f
  34 #define BOUNDING_BOX_RIGHT_X 100.0f
  35 #define BOUNDING_BOX_BOTTOM_Y 50.0f
  36
  37 #define INSIDE_X1 (BOUNDING_BOX_LEFT_X + 1.0f)
  38 #define INSIDE_X2 (BOUNDING_BOX_RIGHT_X - 1.0f)
  39 #define INSIDE_Y1 (BOUNDING_BOX_BOTTOM_Y + 1.0f)
  40 #define INSIDE_Y2 (BOUNDING_BOX_TOP_Y - 1.0f)
  41
  42 #define OUTSIDE_X1 (BOUNDING_BOX_LEFT_X - 1.0f)
  43 #define OUTSIDE_X2 (BOUNDING_BOX_RIGHT_X + 1.0f)
  44 #define OUTSIDE_Y1 (BOUNDING_BOX_BOTTOM_Y - 1.0f)
  45 #define OUTSIDE_Y2 (BOUNDING_BOX_TOP_Y + 1.0f)
  46
  47 static void
  48 populate_clip_context (struct clip_context *ctx)
  49 {
  50         ctx->clip.x1 = BOUNDING_BOX_LEFT_X;
  51         ctx->clip.y1 = BOUNDING_BOX_BOTTOM_Y;
  52         ctx->clip.x2 = BOUNDING_BOX_RIGHT_X;
  53         ctx->clip.y2 = BOUNDING_BOX_TOP_Y;
  54 }
  55
  56 static int
  57 clip_polygon (struct clip_context *ctx,
  58               struct polygon8 *polygon,
  59               GLfloat *vertices_x,
  60               GLfloat *vertices_y)
  61 {
  62         populate_clip_context(ctx);
  63         return clip_transformed(ctx, polygon, vertices_x, vertices_y);
  64 }
  65
  66 struct vertex_clip_test_data
  67 {
  68         struct polygon8 surface;
  69         struct polygon8 expected;
  70 };
  71
  72 const struct vertex_clip_test_data test_data[] =
  73 {
  74         /* All inside */
  75         {
  76                 {
  77                         { INSIDE_X1, INSIDE_X2, INSIDE_X2, INSIDE_X1 },
  78                         { INSIDE_Y1, INSIDE_Y1, INSIDE_Y2, INSIDE_Y2 },
  79                         4
  80                 },
  81                 {
  82                         { INSIDE_X1, INSIDE_X2, INSIDE_X2, INSIDE_X1 },
  83                         { INSIDE_Y1, INSIDE_Y1, INSIDE_Y2, INSIDE_Y2 },
  84                         4
  85                 }
  86         },
  87         /* Top outside */
  88         {
  89                 {
  90                         { INSIDE_X1, INSIDE_X2, INSIDE_X2, INSIDE_X1 },
  91                         { INSIDE_Y1, INSIDE_Y1, OUTSIDE_Y2, OUTSIDE_Y2 },
  92                         4
  93                 },
  94                 {
  95                         { INSIDE_X1, INSIDE_X1, INSIDE_X2, INSIDE_X2 },
  96                         { BOUNDING_BOX_TOP_Y, INSIDE_Y1, INSIDE_Y1, BOUNDING_BOX_TOP_Y },
  97                         4
  98                 }
  99         },
 100         /* Bottom outside */
 101         {
 102                 {
 103                         { INSIDE_X1, INSIDE_X2, INSIDE_X2, INSIDE_X1 },
 104                         { OUTSIDE_Y1, OUTSIDE_Y1, INSIDE_Y2, INSIDE_Y2 },
 105                         4
 106                 },
 107                 {
 108                         { INSIDE_X1, INSIDE_X2, INSIDE_X2, INSIDE_X1 },
 109                         { BOUNDING_BOX_BOTTOM_Y, BOUNDING_BOX_BOTTOM_Y, INSIDE_Y2, INSIDE_Y2 },
 110                         4
 111                 }
 112         },
 113         /* Left outside */
 114         {
 115                 {
 116                         { OUTSIDE_X1, INSIDE_X2, INSIDE_X2, OUTSIDE_X1 },
 117                         { INSIDE_Y1, INSIDE_Y1, INSIDE_Y2, INSIDE_Y2 },
 118                         4
 119                 },
 120                 {
 121                         { BOUNDING_BOX_LEFT_X, INSIDE_X2, INSIDE_X2, BOUNDING_BOX_LEFT_X },
 122                         { INSIDE_Y1, INSIDE_Y1, INSIDE_Y2, INSIDE_Y2 },
 123                         4
 124                 }
 125         },
 126         /* Right outside */
 127         {
 128                 {
 129                         { INSIDE_X1, OUTSIDE_X2, OUTSIDE_X2, INSIDE_X1 },
 130                         { INSIDE_Y1, INSIDE_Y1, INSIDE_Y2, INSIDE_Y2 },
 131                         4
 132                 },
 133                 {
 134                         { INSIDE_X1, BOUNDING_BOX_RIGHT_X, BOUNDING_BOX_RIGHT_X, INSIDE_X1 },
 135                         { INSIDE_Y1, INSIDE_Y1, INSIDE_Y2, INSIDE_Y2 },
 136                         4
 137                 }
 138         },
 139         /* Diamond extending from bounding box edges, clip to bounding box */
 140         {
 141                 {
 142                         { BOUNDING_BOX_LEFT_X - 25, BOUNDING_BOX_LEFT_X + 25, BOUNDING_BOX_RIGHT_X + 25, BOUNDING_BOX_RIGHT_X - 25 },
 143                         { BOUNDING_BOX_BOTTOM_Y + 25, BOUNDING_BOX_TOP_Y + 25, BOUNDING_BOX_TOP_Y - 25, BOUNDING_BOX_BOTTOM_Y - 25 },
 144                         4
 145                 },
 146                 {
 147                         { BOUNDING_BOX_LEFT_X, BOUNDING_BOX_LEFT_X, BOUNDING_BOX_RIGHT_X, BOUNDING_BOX_RIGHT_X },
 148                         { BOUNDING_BOX_BOTTOM_Y, BOUNDING_BOX_TOP_Y, BOUNDING_BOX_TOP_Y, BOUNDING_BOX_BOTTOM_Y },
 149                         4
 150                 }
 151         },
 152         /* Diamond inside of bounding box edges, clip t bounding box, 8 resulting vertices */
 153         {
 154                 {
 155                         { BOUNDING_BOX_LEFT_X - 12.5, BOUNDING_BOX_LEFT_X + 25, BOUNDING_BOX_RIGHT_X + 12.5, BOUNDING_BOX_RIGHT_X - 25 },
 156                         { BOUNDING_BOX_BOTTOM_Y + 25, BOUNDING_BOX_TOP_Y + 12.5, BOUNDING_BOX_TOP_Y - 25, BOUNDING_BOX_BOTTOM_Y - 12.5 },
 157                         4
 158                 },
 159                 {
 160                         { BOUNDING_BOX_LEFT_X + 12.5, BOUNDING_BOX_LEFT_X, BOUNDING_BOX_LEFT_X, BOUNDING_BOX_LEFT_X + 12.5,
 161                           BOUNDING_BOX_RIGHT_X - 12.5, BOUNDING_BOX_RIGHT_X, BOUNDING_BOX_RIGHT_X, BOUNDING_BOX_RIGHT_X - 12.5 },
 162                         { BOUNDING_BOX_BOTTOM_Y, BOUNDING_BOX_BOTTOM_Y + 12.5, BOUNDING_BOX_TOP_Y - 12.5, BOUNDING_BOX_TOP_Y,
 163                           BOUNDING_BOX_TOP_Y, BOUNDING_BOX_TOP_Y - 12.5, BOUNDING_BOX_BOTTOM_Y + 12.5, BOUNDING_BOX_BOTTOM_Y },
 164                         8
 165                 }
 166         }
 167 };
 168
 169 /* clip_polygon modifies the source operand and the test data must
 170  * be const, so we need to deep copy it */
 171 static void
 172 deep_copy_polygon8(const struct polygon8 *src, struct polygon8 *dst)
 173 {
 174         dst->n = src->n;
 175         memcpy((void *) dst->x, src->x, sizeof (src->x));
 176         memcpy((void *) dst->y, src->y, sizeof (src->y));
 177 }
 178
 179 TEST_P(clip_polygon_n_vertices_emitted, test_data)
 180 {
 181         struct vertex_clip_test_data *tdata = data;
 182         struct clip_context ctx;
 183         struct polygon8 polygon;
 184         GLfloat vertices_x[8];
 185         GLfloat vertices_y[8];
 186         deep_copy_polygon8(&tdata->surface, &polygon);
 187         int emitted = clip_polygon(&ctx, &polygon, vertices_x, vertices_y);
 188
 189         assert(emitted == tdata->expected.n);
 190 }
 191
 192 TEST_P(clip_polygon_expected_vertices, test_data)
 193 {
 194         struct vertex_clip_test_data *tdata = data;
 195         struct clip_context ctx;
 196         struct polygon8 polygon;
 197         GLfloat vertices_x[8];
 198         GLfloat vertices_y[8];
 199         deep_copy_polygon8(&tdata->surface, &polygon);
 200         int emitted = clip_polygon(&ctx, &polygon, vertices_x, vertices_y);
 201         int i = 0;
 202
 203         for (; i < emitted; ++i)
 204         {
 205                 assert(vertices_x[i] == tdata->expected.x[i]);
 206                 assert(vertices_y[i] == tdata->expected.y[i]);
 207         }
 208 }
 209
 210 TEST(float_difference_different)
 211 {
 212         assert(float_difference(1.0f, 0.0f) == 1.0f);
 213 }
 214
 215 TEST(float_difference_same)
 216 {
 217         assert(float_difference(1.0f, 1.0f) == 0.0f);
 218 }
 219