Improve the low processor mode sleep precision

The Low Processor Usage Mode Sleep Usec setting is now used as a
FPS limiter rather than a constant sleep duration.

This will increase CPU/GPU usage slightly due to the higher
effective FPS, but the increase in overall smoothness is worth it.

If both Force Fps and Low Processor Usage Mode settings are enabled
in the project settings, only the setting that causes the highest
sleep duration will be retained.

This closes #11030.
This commit is contained in:
Hugo Locurcio 2020-06-15 19:30:39 +02:00
parent 77990b87c2
commit 1c28b269d8
No known key found for this signature in database
GPG key ID: 39E8F8BE30B0A49C

View file

@ -2258,25 +2258,37 @@ bool Main::iteration() {
return exit;
}
if (OS::get_singleton()->is_in_low_processor_usage_mode() || !DisplayServer::get_singleton()->can_any_window_draw()) {
OS::get_singleton()->delay_usec(OS::get_singleton()->get_low_processor_usage_mode_sleep_usec()); //apply some delay to force idle time
} else {
uint32_t frame_delay = Engine::get_singleton()->get_frame_delay();
const uint32_t frame_delay = Engine::get_singleton()->get_frame_delay();
if (frame_delay) {
OS::get_singleton()->delay_usec(Engine::get_singleton()->get_frame_delay() * 1000);
}
// Add fixed frame delay to decrease CPU/GPU usage. This doesn't take
// the actual frame time into account.
// Due to the high fluctuation of the actual sleep duration, it's not recommended
// to use this as a FPS limiter.
OS::get_singleton()->delay_usec(frame_delay * 1000);
}
int target_fps = Engine::get_singleton()->get_target_fps();
// Add a dynamic frame delay to decrease CPU/GPU usage. This takes the
// previous frame time into account for a smoother result.
uint64_t dynamic_delay = 0;
if (OS::get_singleton()->is_in_low_processor_usage_mode() || !DisplayServer::get_singleton()->window_can_draw()) {
dynamic_delay = OS::get_singleton()->get_low_processor_usage_mode_sleep_usec();
}
const int target_fps = Engine::get_singleton()->get_target_fps();
if (target_fps > 0 && !Engine::get_singleton()->is_editor_hint()) {
uint64_t time_step = 1000000L / target_fps;
target_ticks += time_step;
// Override the low processor usage mode sleep delay if the target FPS is lower.
dynamic_delay = MAX(dynamic_delay, (uint64_t)(1000000 / target_fps));
}
if (dynamic_delay > 0) {
target_ticks += dynamic_delay;
uint64_t current_ticks = OS::get_singleton()->get_ticks_usec();
if (current_ticks < target_ticks) {
OS::get_singleton()->delay_usec(target_ticks - current_ticks);
}
current_ticks = OS::get_singleton()->get_ticks_usec();
target_ticks = MIN(MAX(target_ticks, current_ticks - time_step), current_ticks + time_step);
target_ticks = MIN(MAX(target_ticks, current_ticks - dynamic_delay), current_ticks + dynamic_delay);
}
#ifdef TOOLS_ENABLED