tests/general/line-flat-clip-color.c

   1 /*
   2  * Copyright © 2014 VMware, Inc.
   3  *
   4  * Permission is hereby granted, free of charge, to any person obtaining a
   5  * copy of this software and associated documentation files (the "Software"),
   6  * to deal in the Software without restriction, including without limitation
   7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
   8  * and/or sell copies of the Software, and to permit persons to whom the
   9  * Software is furnished to do so, subject to the following conditions:
  10  *
  11  * The above copyright notice and this permission notice (including the next
  12  * paragraph) shall be included in all copies or substantial portions of the
  13  * Software.
  14  *
  15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  18  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  19  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  20  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
  21  * DEALINGS IN THE SOFTWARE.
  22  */
  23
  24 /*
  25  * Test flat-shaded clipped line color.
  26  * Exercises provoking vertex, line smooth, line width, etc.
  27  *
  28  * Author: Brian Paul
  29  */
  30
  31
  32 #include "piglit-util-gl.h"
  33
  34 PIGLIT_GL_TEST_CONFIG_BEGIN
  35         config.supports_gl_compat_version = 10;
  36         config.window_visual = PIGLIT_GL_VISUAL_RGB | PIGLIT_GL_VISUAL_DOUBLE;
  37         config.khr_no_error_support = PIGLIT_NO_ERRORS;
  38 PIGLIT_GL_TEST_CONFIG_END
  39
  40
  41 /* far left, far right verts */
  42 static const float verts[2][2] = {
  43         { -10.0, 0.0 }, { 10.0, 0.0 }
  44 };
  45
  46 static const float colors[2][3] = {
  47         { 1.0, 0.0, 0.0 }, { 0.0, 1.0, 0.0 }
  48 };
  49
  50 static const GLuint forward_order[2] = { 0, 1 };
  51 static const GLuint backward_order[2] = { 1, 0 };
  52
  53 static bool have_pv = false;
  54
  55
  56 static bool
  57 test_one(int order, const float expected[3])
  58 {
  59         bool pass = false;
  60         int dy, y = piglit_height / 2;
  61
  62         glClear(GL_COLOR_BUFFER_BIT);
  63
  64         /* draw horizontal line across middle of window */
  65         if (order == 0)
  66                 glDrawElements(GL_LINES, 2, GL_UNSIGNED_INT, forward_order);
  67         else
  68                 glDrawElements(GL_LINES, 2, GL_UNSIGNED_INT, backward_order);
  69
  70         /* To be resilient in the face of different line rasterization,
  71          * try several Y values to find where the line was drawn.
  72          */
  73         for (dy = -1; dy <= 1; dy++) {
  74                 GLfloat color[3];
  75                 glReadPixels(0, y + dy, 1, 1, GL_RGB, GL_FLOAT, color);
  76                 if (color[0] || color[1] || color[2]) {
  77                         /* found non-black pixel */
  78                         /* test all pixels across middle of window */
  79                         pass = piglit_probe_rect_rgb(0, y + dy, /* x, y */
  80                                                      piglit_width, 1, /* w, h */
  81                                                      expected);
  82                         break;
  83                 }
  84         }
  85
  86         piglit_present_results();
  87
  88         return pass;
  89 }
  90
  91
  92 void
  93 piglit_init(int argc, char **argv)
  94 {
  95         glMatrixMode(GL_PROJECTION);
  96         glLoadIdentity();
  97         glMatrixMode(GL_MODELVIEW);
  98         glLoadIdentity();
  99
 100         glEnable(GL_VERTEX_ARRAY);
 101         glEnable(GL_COLOR_ARRAY);
 102         glVertexPointer(2, GL_FLOAT, 0, verts);
 103         glColorPointer(3, GL_FLOAT, 0, colors);
 104
 105         glShadeModel(GL_FLAT);
 106
 107         if (piglit_is_extension_supported("GL_ARB_provoking_vertex")) {
 108                 have_pv = true;
 109         }
 110         else if (piglit_is_extension_supported("GL_EXT_provoking_vertex")) {
 111                 have_pv = true;
 112         }
 113
 114         if (have_pv)
 115                 printf("Have provoking vertex.\n");
 116 }
 117
 118
 119 enum piglit_result
 120 piglit_display(void)
 121 {
 122         int direction, smooth, pv, width;
 123         bool p, pass = true;
 124
 125         for (pv = 0; pv <= (int) have_pv; pv++) {
 126                 if (pv == 1)
 127                         glProvokingVertex(GL_FIRST_VERTEX_CONVENTION_EXT);
 128
 129                 for (width = 1; width <= 5; width += 4) {
 130                         glLineWidth((float) width);
 131
 132                         for (smooth = 0; smooth <= 1; smooth++) {
 133                                 if (smooth)
 134                                         glEnable(GL_LINE_SMOOTH);
 135                                 else
 136                                         glDisable(GL_LINE_SMOOTH);
 137
 138                                 for (direction = 0; direction <= 1; direction++) {
 139                                         /* Determine which vertex color should
 140                                          * have been used for the line.
 141                                          */
 142                                         int c = !(direction ^ pv);
 143
 144                                         p = test_one(direction, colors[c]);
 145                                         if (!p) {
 146                                                 printf("failure (pv = %d, dir = %d,"
 147                                                        " smooth = %d, width = %d)\n",
 148                                                        pv, direction, smooth, width);
 149                                         }
 150                                         pass = pass && p;
 151                                 }
 152                         }
 153                 }
 154         }
 155
 156         return pass ? PIGLIT_PASS : PIGLIT_FAIL;
 157 }