gltest.cpp

   1 /* gltest - small OpenGL tearing test program
   2  * Copyright (C) 2012-2013 Ralf Jung <post@ralfj.de>
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation; either version 2 of the License, or
   7  * (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program; if not, write to the Free Software
  16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
  17  */
  18
  19 // stdlib includes
  20 #include <time.h>
  21 #include <stdio.h>
  22 #include <stdlib.h>
  23 #include <string.h>
  24 #include <limits.h>
  25 #include <unistd.h>
  26 #include <assert.h>
  27 #include <GL/gl.h>
  28 #include <boost/program_options.hpp>
  29
  30 namespace po = boost::program_options;
  31
  32 // include proper GL connector
  33 #include "glwindow.h"
  34 #if defined(USE_GLX)
  35 #include "glxbackend.h"
  36 static GLBackend *createGLBackend()
  37 {
  38         return new GLXBackend();
  39 }
  40 #elif defined(USE_EGL)
  41 #include "eglbackend.h"
  42 static GLBackend *createGLBackend()
  43 {
  44         return new EGLBackend();
  45 }
  46 #else
  47 #error "No GL window type selected"
  48 #endif
  49
  50 // configuration
  51 static const GLfloat boxWidth = 0.045f;
  52 static const GLfloat boxSpeed = 1.25f; // per second
  53
  54 // profiler
  55 enum ProfilerState { statePreRender, stateClear, stateDraw, statePresent, statePostRender, stateOutsideRender, numProfilerStates };
  56 static const char *profilerStateNames[numProfilerStates] = { "Pre-Render", "Clearing", "Drawing", "Presenting", "Post-Render", "Outside renderer"};
  57
  58 // utility functions
  59 static double getTime()
  60 {
  61         struct timespec tp;
  62         clock_gettime(CLOCK_MONOTONIC, &tp);
  63         return tp.tv_sec + 1e-9 * tp.tv_nsec;
  64 }
  65
  66 static void rectVertices(GLfloat x1, GLfloat y1, GLfloat x2, GLfloat y2)
  67 {
  68         glVertex2f(x1, y1);
  69         glVertex2f(x2, y1);
  70         glVertex2f(x2, y2);
  71         glVertex2f(x1, y2);
  72 }
  73
  74 // the window
  75 class TearTestWindow : public GLWindow {
  76 public:
  77         TearTestWindow(bool overdraw, bool copy, int sleep_time) : GLWindow(XOpenDisplay(0), createGLBackend()),
  78                 overdraw(overdraw), copy(copy), sleep_time(sleep_time), boxPos(0), boxDirection(1)
  79         {}
  80
  81         void setSwapInterval(int i) {
  82                 getBackend()->setSwapInterval(i);
  83         }
  84
  85 protected:
  86         virtual void initGL()
  87         {
  88                 // initialize GL proper
  89                 glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
  90                 glDisable(GL_DEPTH_TEST);
  91                 // initialize clocks
  92                 lastFrame = getTime();
  93                 // initailize profiler
  94                 framect = 0;
  95                 memset(stateTime, 0, sizeof(stateTime));
  96                 curState = -1;
  97                 lastDisplay = lastProfile = getTime();
  98         }
  99
 100         virtual void resizeGL(unsigned int width, unsigned int height)
 101         {
 102                 /* prevent divide-by-zero */
 103                 if (height == 0)
 104                         height = 1;
 105                 glViewport(0, 0, width, height);
 106                 glMatrixMode(GL_PROJECTION);
 107                 glLoadIdentity();
 108                 glOrtho (0, 1, 1, 0, 0, 1);
 109                 glMatrixMode(GL_MODELVIEW);
 110                 glClear(GL_COLOR_BUFFER_BIT);
 111                 glFlush();
 112         }
 113
 114         void profilerTick(ProfilerState nextState)
 115         {
 116                 assert (nextState >= 0 && nextState < numProfilerStates);
 117                 double time = getTime();
 118                 if (curState >= 0)
 119                         stateTime[curState] += time-lastProfile;
 120                 curState = nextState;
 121                 lastProfile = time;
 122                 // display?
 123                 const double elapsed = time-lastDisplay;
 124                 if (elapsed >= 3) {
 125                         printf("%.1f fps, time spent: ", framect/elapsed);
 126                         for (int i = 0; i < numProfilerStates; ++i) {
 127                                 if (i != 0) printf(", ");
 128                                 printf("%s %.1f%%", profilerStateNames[i], stateTime[i]/elapsed*100);
 129                         }
 130                         printf("\n");
 131                         lastDisplay = time;
 132                         framect = 0;
 133                         memset(stateTime, 0, sizeof(stateTime));
 134                 }
 135         }
 136
 137         void renderGL()
 138         {
 139                 //////////////////////////////////////////////
 140                 profilerTick(statePreRender);
 141                 double time = getTime();
 142                 // anim
 143                 double passedTime = time-lastFrame;
 144                 boxPos += boxSpeed*passedTime*boxDirection;
 145                 while (boxPos < 0 || boxPos+boxWidth > 1) { // wrapover
 146                         if (boxPos < 0) {
 147                                 boxPos = -boxPos;
 148                                 boxDirection = -boxDirection;
 149                         }
 150                         else {
 151                                 boxPos = 1.0-boxWidth-(boxPos+boxWidth-1.0);
 152                                 boxDirection = -boxDirection;
 153                         }
 154                 }
 155                 lastFrame = time;
 156                 //////////////////////////////////////////////
 157                 profilerTick(stateClear);
 158                 if (overdraw) {
 159                         // clear manually
 160                         glBegin(GL_QUADS);
 161                         glColor3f(0.0f, 0.0f, 0.0f);
 162                         rectVertices(0, 0, 1, 1);
 163                         glEnd();
 164                 }
 165                 else {
 166                         glClear(GL_COLOR_BUFFER_BIT);
 167                 }
 168                 //////////////////////////////////////////////
 169                 profilerTick(stateDraw);
 170                 glBegin(GL_QUADS);
 171                 glColor3f(0.8f, 1.0f, 0.75f);
 172                 rectVertices(boxPos, 0, boxPos+boxWidth, 1);
 173                 glEnd();
 174                 usleep(sleep_time*1000);
 175                 //////////////////////////////////////////////
 176                 profilerTick(statePresent);
 177                 if (copy) {
 178                         glDrawBuffer(GL_FRONT);
 179                         glCopyPixels(0, 0, getWidth(), getHeight(), GL_COLOR);
 180                         glDrawBuffer(GL_BACK);
 181                 }
 182                 else {
 183                         getBackend()->swapBuffers();
 184                 }
 185                 //////////////////////////////////////////////
 186                 profilerTick(statePostRender);
 187                 glFlush();
 188                 ++framect;
 189                 //////////////////////////////////////////////
 190                 profilerTick(stateOutsideRender);
 191         }
 192
 193         virtual void handleKeyPress(KeySym key)
 194         {
 195                 switch (key) {
 196                         case XK_Escape: close(); break;
 197                         case XK_F1: setFullscreen(!getFullscreen()); break;
 198                         default: break;
 199                 }
 200         }
 201
 202 private:
 203         bool overdraw, copy;
 204         int sleep_time;
 205         // animation control
 206         double lastFrame;
 207         GLfloat boxPos, boxDirection;
 208         // FPS, profiler
 209         double lastDisplay, lastProfile;
 210         int framect, curState;
 211         double stateTime[numProfilerStates];
 212 };
 213
 214 int main(int argc, char ** argv)
 215 {
 216         // program options handling
 217         po::options_description desc("Allowed options");
 218         desc.add_options()
 219                 ("help,h", "produce help message")
 220                 ("swap-interval,i", po::value<int>(), "set swap interval")
 221                 ("copy,c", "copy to front buffer (instead of performing a buffer swap)")
 222                 ("overdraw,o", "overdraw previous image (instead of calling glClear)")
 223                 ("sleep,s", po::value<int>()->default_value(0), "Number of milliseconds to sleap in each frame (in the drawing phase)")
 224         ;
 225         po::variables_map vm;
 226         po::store(po::parse_command_line(argc, argv, desc), vm);
 227         po::notify(vm);
 228
 229         if (vm.count("help")) {
 230                 std::cout << desc << "\n";
 231                 return 1;
 232         }
 233
 234         // actual program
 235         TearTestWindow w(vm.count("overdraw"), vm.count("copy"), vm["sleep"].as<int>());
 236         w.open(800, 600);
 237         if (vm.count("swap-interval"))
 238                 w.setSwapInterval(vm["swap-interval"].as<int>());
 239         w.exec();
 240 }