tests/spec/arb_viewport_array/render_viewport.c

   1 /*
   2  * Copyright © 2013 LunarG, 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 DEALINGS
  21  * IN THE SOFTWARE.
  22  *
  23  * Author: Jon Ashburn <jon@lunarg.com>
  24  */
  25
  26 /**
  27  * Tests rendering into a single framebuffer surface with multiple viewports
  28  * via a geometry shader.  Confirm that each area of the surface delineated by
  29  * a viewport renders the correct color. Use multiple draw
  30  * calls to replicate geometry rather than the geometry shader.
  31  * From the extension registry for ARB_viewport_array:
  32  *    "This extension enhances OpenGL by providing a mechanism to expose
  33  *    multiple viewports. Each viewport is specified as a rectangle. The
  34  *    destination viewport may be selected per-primitive by the geometry
  35  *    shader. This allows the Geometry Shader to produce different versions
  36  *    of primitives destined for separate viewport rectangles on the same
  37  *    surface.
  38  */
  39 #include "piglit-util-gl.h"
  40
  41 PIGLIT_GL_TEST_CONFIG_BEGIN
  42
  43         config.supports_gl_compat_version = 32;
  44         config.supports_gl_core_version = 32;
  45         config.supports_gl_es_version = 31;
  46
  47         config.window_visual = PIGLIT_GL_VISUAL_RGBA | PIGLIT_GL_VISUAL_DOUBLE;
  48         config.khr_no_error_support = PIGLIT_NO_ERRORS;
  49
  50 PIGLIT_GL_TEST_CONFIG_END
  51
  52 #ifdef PIGLIT_USE_OPENGL
  53 #define GLSL_VERSION "150"
  54 #else
  55 #define GLSL_VERSION "310 es"
  56 #endif
  57
  58 const char *vsSource = {
  59         "#version " GLSL_VERSION "\n"
  60         "in vec4 piglit_vertex;\n"
  61         "void main() {\n"
  62         "       gl_Position = piglit_vertex;\n"
  63         "}\n"
  64 };
  65
  66 const char *gsSource = {
  67         "#version " GLSL_VERSION "\n"
  68         "#extension GL_ARB_viewport_array : enable\n"
  69         "#extension GL_OES_viewport_array : enable\n"
  70         "#extension GL_EXT_geometry_shader : enable\n"
  71         "#extension GL_OES_geometry_shader : enable\n"
  72         "layout(triangles) in;\n"
  73         "layout(triangle_strip, max_vertices = 3) out;\n"
  74         "uniform int idx;\n"
  75         "\n"
  76         "void main()\n"
  77         "{\n"
  78         "       gl_ViewportIndex = idx;\n"
  79         "       for(int i = 0; i < gl_in.length(); i++) {\n"
  80         "               gl_Position = gl_in[i].gl_Position;\n"
  81         "               EmitVertex();\n"
  82         "       }\n"
  83         "       EndPrimitive();\n"
  84         "}\n"
  85 };
  86
  87 const char *fsSource = {
  88         "#version " GLSL_VERSION "\n"
  89         "#ifdef GL_ES\n"
  90         "precision highp float;\n"
  91         "#endif\n"
  92         "uniform vec3 color;\n"
  93         "out vec4 c;\n"
  94         "void main() {\n"
  95         "       c = vec4(color.xyz, 1.0);\n"
  96         "}\n"
  97 };
  98
  99 static GLint colorLoc;
 100 static GLint vpIndexLoc;
 101
 102 /**
 103  * Draws a single quad into multiple viewport  each with a different
 104  * color.  Reads back the expected color  to test if the drawing was correct.
 105  * @param  changeVPloc;   if true then the geometry shader viewport location
 106  *         is changed with each loop, otherwise viewport location is fixed.
 107  */
 108 static bool
 109 draw_multi_viewport(const bool changeVPLoc)
 110 {
 111         bool pass = true;
 112         int i, j;
 113         const int divX=2, divY=4;
 114         GLfloat w = (GLfloat) piglit_width / (GLfloat) divX;
 115         GLfloat h = (GLfloat) piglit_height / (GLfloat) divY;
 116         const GLfloat colors[][4] = {{0.0, 0.0, 1.0, 1.0},
 117                                      {0.0, 1.0, 0.0, 1.0},
 118                                      {1.0, 0.0, 0.0, 1.0},
 119                                      {1.0, 1.0, 0.0, 1.0},
 120                                      {0.0, 1.0, 1.0, 1.0},
 121                                      {1.0, 0.0, 1.0, 1.0},
 122                                      {1.0, 1.0, 1.0, 1.0},
 123                                      {0.0, 0.0, 0.5, 1.0},
 124                                      {0.0, 0.0, 0.0, 0.0}};
 125
 126         assert(ARRAY_SIZE(colors) == divX*divY + 1);
 127
 128         glViewport(0, 0, piglit_width, piglit_height); /* for glClear() */
 129         glClear(GL_COLOR_BUFFER_BIT);
 130         glUniform1i(vpIndexLoc, divX * divY);
 131         glViewportIndexedf(divX * divY, -10.0, -30.0, piglit_width, 20.0);
 132         for (i = 0; i < divX; i++) {
 133                 for (j = 0; j < divY; j++) {
 134                         int p;
 135                         GLfloat *expected;
 136                         glUniform3fv(colorLoc, 1, &colors[j + i*divY][0]);
 137                         if (changeVPLoc) {
 138                                 glUniform1i(vpIndexLoc, j + i*divY);
 139                                 expected = (GLfloat *) &colors[j + i*divY][0];
 140                         } else  {
 141                                 expected = (GLfloat *) &colors[divX * divY][0];
 142                         }
 143                         glViewportIndexedf(j + i*divY, i * w, j * h, w, h);
 144                         piglit_draw_rect(-1, -1, 2, 2);
 145                         pass = piglit_check_gl_error(GL_NO_ERROR) && pass;
 146                         p = piglit_probe_pixel_rgba(i * w + w/2, j * h + h/2,
 147                                                     expected);
 148                         piglit_present_results();
 149                         if (!p) {
 150                                 printf("Wrong color for viewport i,j %d %d changeVP=%d\n",
 151                                        i, j, changeVPLoc);
 152                                 pass = false;
 153                         }
 154                 }
 155         }
 156         return pass;
 157 }
 158
 159 enum piglit_result
 160 piglit_display(void)
 161 {
 162         bool pass = true;
 163
 164         pass = draw_multi_viewport(true);
 165         pass = draw_multi_viewport(false) && pass;
 166         pass = piglit_check_gl_error(GL_NO_ERROR) && pass;
 167         return pass ? PIGLIT_PASS : PIGLIT_FAIL;
 168 }
 169
 170 void
 171 piglit_init(int argc, char **argv)
 172 {
 173         GLuint program;
 174
 175 #ifdef PIGLIT_USE_OPENGL
 176         piglit_require_extension("GL_ARB_viewport_array");
 177 #else
 178         piglit_require_extension("GL_OES_viewport_array");
 179 #endif
 180
 181         program = piglit_build_simple_program_multiple_shaders(
 182                                         GL_VERTEX_SHADER, vsSource,
 183                                         GL_GEOMETRY_SHADER, gsSource,
 184                                         GL_FRAGMENT_SHADER, fsSource,
 185                                         0);
 186         glUseProgram(program);
 187         colorLoc = glGetUniformLocation(program, "color");
 188         vpIndexLoc = glGetUniformLocation(program, "idx");
 189 }