time video frames instead of game frames

This commit is contained in:
fgsfds 2020-07-08 13:07:05 +03:00
parent 92e869d263
commit 2982fcdb8e
1 changed files with 9 additions and 4 deletions

View File

@ -54,6 +54,7 @@ static void (*kb_all_keys_up)(void) = NULL;
static bool use_timer = true;
// time between consequtive game frames
static const Uint32 frame_time = 1000 / FRAMERATE;
static Uint32 frame_start = 0;
const SDL_Scancode windows_scancode_table[] = {
/* 0 1 2 3 4 5 6 7 */
@ -239,11 +240,7 @@ static void gfx_sdl_init(const char *window_title) {
}
static void gfx_sdl_main_loop(void (*run_one_game_iter)(void)) {
Uint32 t = SDL_GetTicks();
run_one_game_iter();
t = SDL_GetTicks() - t;
if (t < frame_time && use_timer)
SDL_Delay(frame_time - t);
}
static void gfx_sdl_get_dimensions(uint32_t *width, uint32_t *height) {
@ -327,10 +324,18 @@ static void gfx_sdl_set_keyboard_callbacks(kb_callback_t on_key_down, kb_callbac
}
static bool gfx_sdl_start_frame(void) {
frame_start = SDL_GetTicks();
return true;
}
static inline void sync_framerate_with_timer(void) {
const Uint32 elapsed = SDL_GetTicks() - frame_start;
if (elapsed < frame_time)
SDL_Delay(frame_time - elapsed);
}
static void gfx_sdl_swap_buffers_begin(void) {
if (use_timer) sync_framerate_with_timer();
SDL_GL_SwapWindow(wnd);
}