cdo/retro-rpg
2
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

Measure game code performance in engine

Browse Source
This commit is contained in:
Camden Dixie O'Brien 2025-01-02 15:35:57 +00:00
parent d9981d8d61
commit bbaf58869a
1 changed files with 36 additions and 7 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

43
engine/engine.c
View File

@ -13,6 +13,14 @@
#define FRAMERATE 60 #define FRAMERATE 60
#define INTERVAL (1000 / FRAMERATE) #define INTERVAL (1000 / FRAMERATE)
#define VT100_CURSORTOPLEFT "\33[H"
#define VT100_CLEAR "\33[2J"
typedef struct {
double freq;
uint64_t start, evt, update, render;
} perf_t;
int main(int argc, char *argv[]) int main(int argc, char *argv[])
{ {
int err = SDL_Init(SDL_INIT_VIDEO); int err = SDL_Init(SDL_INIT_VIDEO);
@ -29,33 +37,54 @@ int main(int argc, char *argv[])
void *gamemem = calloc(1, game_conf.memsize); void *gamemem = calloc(1, game_conf.memsize);
game_init(argc, argv, gamemem, renderer); game_init(argc, argv, gamemem, renderer);
uint64_t prevt = SDL_GetTicks64(); perf_t perf = { .freq = SDL_GetPerformanceFrequency() / 1000000.0 };
uint64_t frame = 0, prevt = SDL_GetTicks64();
while (1) { while (1) {
uint64_t t = SDL_GetTicks64(); const uint64_t t = SDL_GetTicks64();
uint64_t dt = t - prevt; const uint64_t dt = t - prevt;
if (dt >= INTERVAL) { if (dt >= INTERVAL) {
perf.start = SDL_GetPerformanceCounter();
// Handle all events currently in queue // Handle all events currently in queue
SDL_Event evt; SDL_Event evt;
while (SDL_PollEvent(&evt)) { while (SDL_PollEvent(&evt)) {
if (game_evthandle(gamemem, &evt) != GAMESTATUS_OK) if (game_evthandle(gamemem, &evt) != GAMESTATUS_OK)
goto quit; goto quit;
} }
perf.evt = SDL_GetPerformanceCounter();
// Update game state // Update game state
if (game_update(gamemem, dt) != GAMESTATUS_OK) if (game_update(gamemem, INTERVAL) != GAMESTATUS_OK)
goto quit; goto quit;
perf.update = SDL_GetPerformanceCounter();
// Render frame // Render frame
SDL_RenderClear(renderer); SDL_RenderClear(renderer);
game_render(gamemem, renderer, t); game_render(gamemem, renderer, t);
SDL_RenderPresent(renderer); SDL_RenderPresent(renderer);
perf.render = SDL_GetPerformanceCounter();
// Set previous frame draw time // Print performance if frame counter divisible by 8
if ((frame & 7) == 0) {
const double evt = (perf.evt - perf.start) / perf.freq;
const double update = (perf.update - perf.evt) / perf.freq;
const double render
= (perf.render - perf.update) / perf.freq;
const double total = (perf.render - perf.start) / perf.freq;
const double total_pc = (100 * total / (1000 * INTERVAL));
printf(
VT100_CLEAR VT100_CURSORTOPLEFT
"evt\t%10.3f μs\nupdate\t%10.3f μs\nrender\t"
"%10.3f μs\ntotal\t%10.3f μs (%05.2f%%)\n",
evt, update, render, total, total_pc);
}
// Increment frame counter and update time
++frame;
prevt = t; prevt = t;
} }
SDL_Delay(2); SDL_Delay(INTERVAL / 8);
} }
quit: quit: