game.cpp

static bool STATS = false;
static const int FRAME_PLOT_SIZE = 50;
static float frameTimes[FRAME_PLOT_SIZE];

void renderUIElements(float elapsed) {
  if (STATS) {
    std::ostringstream os;
    os << "T: " << elapsed;
    std::string str = os.str();
    char * cstr = new char [str.length()+1];
    std::strcpy (cstr, str.c_str());

    ImGui::Begin("Stats");

    for(int i = 0; i < FRAME_PLOT_SIZE - 1; i++) {
      frameTimes[i] = frameTimes[i+1];
    }
    frameTimes[FRAME_PLOT_SIZE-1] = elapsed;

    // Frame Rate
    ImGui::PlotHistogram(cstr, frameTimes, FRAME_PLOT_SIZE, 0, NULL, 0, 0.1f);
    ImGui::End();
  }
}