taisei/src/eventloop/executor_synchro.c
2024-05-17 14:11:48 +02:00

137 lines
3.6 KiB
C

/*
* This software is licensed under the terms of the MIT License.
* See COPYING for further information.
* ---
* Copyright (c) 2011-2024, Lukas Weber <laochailan@web.de>.
* Copyright (c) 2012-2024, Andrei Alexeyev <akari@taisei-project.org>.
*/
#include "eventloop_private.h"
#include "global.h"
#include "thread.h"
#include "util/env.h"
void eventloop_run(void) {
assert(thread_current_is_main());
if(evloop.stack_ptr == NULL) {
return;
}
LoopFrame *frame = evloop.stack_ptr;
evloop.frame_times.target = frame->frametime;
evloop.frame_times.start = time_get();
evloop.frame_times.next = evloop.frame_times.start + evloop.frame_times.target;
int32_t sleep = env_get("TAISEI_FRAMELIMITER_SLEEP", 3);
bool compensate = env_get("TAISEI_FRAMELIMITER_COMPENSATE", 1);
bool uncapped_rendering_env, uncapped_rendering;
if(global.is_replay_verification) {
uncapped_rendering_env = false;
} else {
uncapped_rendering_env = env_get("TAISEI_FRAMELIMITER_LOGIC_ONLY", 0);
}
uncapped_rendering = uncapped_rendering_env;
uint32_t frame_num = 0;
begin_main_loop:
while(frame != NULL) {
#ifdef DEBUG
if(uncapped_rendering_env) {
uncapped_rendering = !gamekeypressed(KEY_FPSLIMIT_OFF);
}
#endif
evloop.frame_times.start = time_get();
begin_frame:
global.fps.busy.last_update_time = time_get();
evloop.frame_times.target = frame->frametime;
++frame_num;
LogicFrameAction lframe_action = LFRAME_WAIT;
if(uncapped_rendering) {
attr_unused uint32_t logic_frames = 0;
while(lframe_action != LFRAME_STOP && evloop.frame_times.next < evloop.frame_times.start) {
lframe_action = handle_logic(&frame, &evloop.frame_times);
if(!frame || lframe_action == LFRAME_STOP) {
goto begin_main_loop;
}
++logic_frames;
hrtime_t total = time_get() - evloop.frame_times.start;
if(total > evloop.frame_times.target) {
evloop.frame_times.next = evloop.frame_times.start;
log_debug("Executing logic took too long (%"PRIuTIME"), giving up", total);
} else {
evloop.frame_times.next += evloop.frame_times.target;
}
}
if(logic_frames > 1) {
log_debug(
"Dropped %u logic frame%s in superframe #%u",
logic_frames - 1,
logic_frames > 2 ? "s" : "",
frame_num
);
}
} else {
lframe_action = handle_logic(&frame, &evloop.frame_times);
if(!frame || lframe_action == LFRAME_STOP) {
goto begin_main_loop;
}
}
if((uncapped_rendering || !(frame_num % get_effective_frameskip())) && !global.is_replay_verification) {
run_render_frame(frame);
}
fpscounter_update(&global.fps.busy);
if(uncapped_rendering || global.frameskip > 0 || global.is_replay_verification) {
continue;
}
#ifdef DEBUG
if(gamekeypressed(KEY_FPSLIMIT_OFF)) {
continue;
}
#endif
evloop.frame_times.next = evloop.frame_times.start + evloop.frame_times.target;
if(compensate) {
hrtime_t rt = time_get();
if(rt > evloop.frame_times.next) {
// frame took too long...
// try to compensate in the next frame to avoid slowdown
evloop.frame_times.start = rt - min(rt - evloop.frame_times.next, evloop.frame_times.target);
goto begin_frame;
}
}
if(sleep > 0) {
// CAUTION: All of these casts are important!
while((shrtime_t)evloop.frame_times.next - (shrtime_t)time_get() > (shrtime_t)evloop.frame_times.target / sleep) {
uint32_t nap_multiplier = 1;
uint32_t nap_divisor = 3;
hrtime_t nap_raw = max(0, (shrtime_t)evloop.frame_times.next - (shrtime_t)time_get());
uint32_t nap_sdl = (nap_multiplier * nap_raw * 1000) / (HRTIME_RESOLUTION * nap_divisor);
nap_sdl = max(nap_sdl, 1);
SDL_Delay(nap_sdl);
}
}
while(time_get() < evloop.frame_times.next);
}
}