mirror of
https://github.com/godotengine/godot.git
synced 2024-12-27 11:24:59 +08:00
b5334d14f7
Happy new year to the wonderful Godot community!
2020 has been a tough year for most of us personally, but a good year for
Godot development nonetheless with a huge amount of work done towards Godot
4.0 and great improvements backported to the long-lived 3.2 branch.
We've had close to 400 contributors to engine code this year, authoring near
7,000 commit! (And that's only for the `master` branch and for the engine code,
there's a lot more when counting docs, demos and other first-party repos.)
Here's to a great year 2021 for all Godot users 🎆
103 lines
4.7 KiB
C++
103 lines
4.7 KiB
C++
/*************************************************************************/
|
|
/* main_timer_sync.h */
|
|
/*************************************************************************/
|
|
/* This file is part of: */
|
|
/* GODOT ENGINE */
|
|
/* https://godotengine.org */
|
|
/*************************************************************************/
|
|
/* Copyright (c) 2007-2021 Juan Linietsky, Ariel Manzur. */
|
|
/* Copyright (c) 2014-2021 Godot Engine contributors (cf. AUTHORS.md). */
|
|
/* */
|
|
/* Permission is hereby granted, free of charge, to any person obtaining */
|
|
/* a copy of this software and associated documentation files (the */
|
|
/* "Software"), to deal in the Software without restriction, including */
|
|
/* without limitation the rights to use, copy, modify, merge, publish, */
|
|
/* distribute, sublicense, and/or sell copies of the Software, and to */
|
|
/* permit persons to whom the Software is furnished to do so, subject to */
|
|
/* the following conditions: */
|
|
/* */
|
|
/* The above copyright notice and this permission notice shall be */
|
|
/* included in all copies or substantial portions of the Software. */
|
|
/* */
|
|
/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, */
|
|
/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF */
|
|
/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.*/
|
|
/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY */
|
|
/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, */
|
|
/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE */
|
|
/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */
|
|
/*************************************************************************/
|
|
|
|
#ifndef MAIN_TIMER_SYNC_H
|
|
#define MAIN_TIMER_SYNC_H
|
|
|
|
#include "core/config/engine.h"
|
|
|
|
struct MainFrameTime {
|
|
float process_step; // delta time to advance during process()
|
|
int physics_steps; // number of times to iterate the physics engine
|
|
float interpolation_fraction; // fraction through the current physics tick
|
|
|
|
void clamp_process_step(float min_process_step, float max_process_step);
|
|
};
|
|
|
|
class MainTimerSync {
|
|
// wall clock time measured on the main thread
|
|
uint64_t last_cpu_ticks_usec = 0;
|
|
uint64_t current_cpu_ticks_usec = 0;
|
|
|
|
// logical game time since last physics timestep
|
|
float time_accum = 0;
|
|
|
|
// current difference between wall clock time and reported sum of process_steps
|
|
float time_deficit = 0;
|
|
|
|
// number of frames back for keeping accumulated physics steps roughly constant.
|
|
// value of 12 chosen because that is what is required to make 144 Hz monitors
|
|
// behave well with 60 Hz physics updates. The only worse commonly available refresh
|
|
// would be 85, requiring CONTROL_STEPS = 17.
|
|
static const int CONTROL_STEPS = 12;
|
|
|
|
// sum of physics steps done over the last (i+1) frames
|
|
int accumulated_physics_steps[CONTROL_STEPS];
|
|
|
|
// typical value for accumulated_physics_steps[i] is either this or this plus one
|
|
int typical_physics_steps[CONTROL_STEPS];
|
|
|
|
int fixed_fps = 0;
|
|
|
|
protected:
|
|
// returns the fraction of p_physics_step required for the timer to overshoot
|
|
// before advance_core considers changing the physics_steps return from
|
|
// the typical values as defined by typical_physics_steps
|
|
float get_physics_jitter_fix();
|
|
|
|
// gets our best bet for the average number of physics steps per render frame
|
|
// return value: number of frames back this data is consistent
|
|
int get_average_physics_steps(float &p_min, float &p_max);
|
|
|
|
// advance physics clock by p_process_step, return appropriate number of steps to simulate
|
|
MainFrameTime advance_core(float p_physics_step, int p_physics_fps, float p_process_step);
|
|
|
|
// calls advance_core, keeps track of deficit it adds to animaption_step, make sure the deficit sum stays close to zero
|
|
MainFrameTime advance_checked(float p_physics_step, int p_physics_fps, float p_process_step);
|
|
|
|
// determine wall clock step since last iteration
|
|
float get_cpu_process_step();
|
|
|
|
public:
|
|
MainTimerSync();
|
|
|
|
// start the clock
|
|
void init(uint64_t p_cpu_ticks_usec);
|
|
// set measured wall clock time
|
|
void set_cpu_ticks_usec(uint64_t p_cpu_ticks_usec);
|
|
//set fixed fps
|
|
void set_fixed_fps(int p_fixed_fps);
|
|
|
|
// advance one frame, return timesteps to take
|
|
MainFrameTime advance(float p_physics_step, int p_physics_fps);
|
|
};
|
|
|
|
#endif // MAIN_TIMER_SYNC_H
|