gltest.cpp

   1 // stdlib includes
   2 #include <time.h>
   3 #include <stdio.h>
   4 #include <stdlib.h>
   5 #include <string.h>
   6 #include <limits.h>
   7 #include <unistd.h>
   8 #include <assert.h>
   9 #include <GL/gl.h>
  10 #include <boost/program_options.hpp>
  11
  12 namespace po = boost::program_options;
  13
  14 // include proper GL connector
  15 #include "glwindow.h"
  16 #if defined(USE_GLX)
  17 #include "glxbackend.h"
  18 static GLBackend *createGLBackend()
  19 {
  20         return new GLXBackend();
  21 }
  22 #elif defined(USE_EGL)
  23 #include "eglbackend.h"
  24 static GLBackend *createGLBackend()
  25 {
  26         return new EGLBackend();
  27 }
  28 #else
  29 #error "No GL window type selected"
  30 #endif
  31
  32 // configuration
  33 static const GLfloat boxWidth = 0.045f;
  34 static const GLfloat boxSpeed = 1.25f; // per second
  35
  36 // profiler
  37 enum ProfilerState { statePreRender, stateClear, stateDraw, statePresent, statePostRender, stateOutsideRender, numProfilerStates };
  38 static const char *profilerStateNames[numProfilerStates] = { "Pre-Render", "Clearing", "Drawing", "Presenting", "Post-Render", "Outside renderer"};
  39
  40 // utility functions
  41 static double getTime()
  42 {
  43         struct timespec tp;
  44         clock_gettime(CLOCK_MONOTONIC, &tp);
  45         return tp.tv_sec + 1e-9 * tp.tv_nsec;
  46 }
  47
  48 static void drawRect(GLfloat x1, GLfloat y1, GLfloat x2, GLfloat y2)
  49 {
  50         glVertex2f(x1, y1); glVertex2f(x2, y1); glVertex2f(x2, y2); glVertex2f(x1, y2);
  51 }
  52
  53 // the window
  54 class TearTestWindow : public GLWindow {
  55 public:
  56         TearTestWindow(bool overdraw, bool copy) : GLWindow(XOpenDisplay(0), createGLBackend()), overdraw(overdraw), copy(copy), boxPos(0), boxDirection(1)
  57         {}
  58
  59         void setSwapInterval(int i) {
  60                 getBackend()->setSwapInterval(i);
  61         }
  62
  63 protected:
  64         virtual void initGL()
  65         {
  66                 // initialize GL proper
  67                 glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
  68                 glDisable(GL_DEPTH_TEST);
  69                 // initialize clocks
  70                 lastFrame = getTime();
  71                 // initailize profiler
  72                 framect = 0;
  73                 memset(stateTime, 0, sizeof(stateTime));
  74                 curState = -1;
  75                 lastDisplay = lastProfile = getTime();
  76         }
  77
  78         virtual void resizeGL(unsigned int width, unsigned int height)
  79         {
  80                 /* prevent divide-by-zero */
  81                 if (height == 0)
  82                         height = 1;
  83                 glViewport(0, 0, width, height);
  84                 glMatrixMode(GL_PROJECTION);
  85                 glLoadIdentity();
  86                 glOrtho (0, 1, 1, 0, 0, 1);
  87                 glMatrixMode(GL_MODELVIEW);
  88                 glClear(GL_COLOR_BUFFER_BIT);
  89                 glFlush();
  90         }
  91
  92         void profilerTick(ProfilerState nextState)
  93         {
  94                 assert (nextState >= 0 && nextState < numProfilerStates);
  95                 double time = getTime();
  96                 if (curState >= 0)
  97                         stateTime[curState] += time-lastProfile;
  98                 curState = nextState;
  99                 lastProfile = time;
 100                 // display?
 101                 const double elapsed = time-lastDisplay;
 102                 if (elapsed >= 3) {
 103                         printf("%.1f fps, time spent: ", framect/elapsed);
 104                         for (int i = 0; i < numProfilerStates; ++i) {
 105                                 if (i != 0) printf(", ");
 106                                 printf("%s %.1f%%", profilerStateNames[i], stateTime[i]/elapsed*100);
 107                         }
 108                         printf("\n");
 109                         lastDisplay = time;
 110                         framect = 0;
 111                         memset(stateTime, 0, sizeof(stateTime));
 112                 }
 113         }
 114
 115         void renderGL()
 116         {
 117                 //////////////////////////////////////////////
 118                 profilerTick(statePreRender);
 119                 double time = getTime();
 120                 // anim
 121                 double passedTime = time-lastFrame;
 122                 boxPos += boxSpeed*passedTime*boxDirection;
 123                 while (boxPos < 0 || boxPos+boxWidth > 1) { // wrapover
 124                         if (boxPos < 0) {
 125                                 boxPos = -boxPos;
 126                                 boxDirection = -boxDirection;
 127                         }
 128                         else {
 129                                 boxPos = 1.0-boxWidth-(boxPos+boxWidth-1.0);
 130                                 boxDirection = -boxDirection;
 131                         }
 132                 }
 133                 lastFrame = time;
 134                 //////////////////////////////////////////////
 135                 profilerTick(stateClear);
 136                 if (overdraw) {
 137                         // clear manually
 138                         glBegin(GL_QUADS);
 139                         glColor3f(0.0f, 0.0f, 0.0f);
 140                         drawRect(0, 0, 1, 1);
 141                         glEnd();
 142                 }
 143                 else {
 144                         glClear(GL_COLOR_BUFFER_BIT);
 145                 }
 146                 //////////////////////////////////////////////
 147                 profilerTick(stateDraw);
 148                 glBegin(GL_QUADS);
 149                 glColor3f(0.8f, 1.0f, 0.75f);
 150                 drawRect(boxPos, 0, boxPos+boxWidth, 1);
 151                 glEnd();
 152                 //////////////////////////////////////////////
 153                 profilerTick(statePresent);
 154                 if (copy) {
 155                         glDrawBuffer(GL_FRONT);
 156                         glCopyPixels(0, 0, getWidth(), getHeight(), GL_COLOR);
 157                         glDrawBuffer(GL_BACK);
 158                 }
 159                 else {
 160                         getBackend()->swapBuffers();
 161                 }
 162                 //////////////////////////////////////////////
 163                 profilerTick(statePostRender);
 164                 glFlush();
 165                 ++framect;
 166                 //////////////////////////////////////////////
 167                 profilerTick(stateOutsideRender);
 168         }
 169
 170         virtual void handleKeyPress(KeySym key)
 171         {
 172                 switch (key) {
 173                         case XK_Escape: close(); break;
 174                         case XK_F1: setFullscreen(!getFullscreen()); break;
 175                         default: break;
 176                 }
 177         }
 178
 179 private:
 180         bool overdraw, copy;
 181         double lastFrame;
 182         GLfloat boxPos, boxDirection;
 183         // FPS
 184         double lastDisplay, lastProfile;
 185         int framect, curState;
 186         double stateTime[numProfilerStates];
 187 };
 188
 189 int main(int argc, char ** argv)
 190 {
 191         // program options handling
 192         po::options_description desc("Allowed options");
 193         desc.add_options()
 194                 ("help,h", "produce help message")
 195                 ("swap-interval,i", po::value<int>(), "set swap interval")
 196                 ("copy,c", "copy to front buffer (instead of performing a buffer swap)")
 197                 ("overdraw,o", "overdraw previous image (instead of calling glClear)")
 198         ;
 199         po::variables_map vm;
 200         po::store(po::parse_command_line(argc, argv, desc), vm);
 201         po::notify(vm);
 202
 203         if (vm.count("help")) {
 204                 std::cout << desc << "\n";
 205                 return 1;
 206         }
 207
 208         // actual program
 209         TearTestWindow w(vm.count("overdraw"), vm.count("copy"));
 210         w.open(800, 600);
 211         if (vm.count("swap-interval"))
 212                 w.setSwapInterval(vm["swap-interval"].as<int>());
 213         w.exec();
 214 }