godot/scene/3d/spatial_velocity_tracker.cpp
Rémi Verschelde a7f49ac9a1 Update copyright statements to 2020
Happy new year to the wonderful Godot community!

We're starting a new decade with a well-established, non-profit, free
and open source game engine, and tons of further improvements in the
pipeline from hundreds of contributors.

Godot will keep getting better, and we're looking forward to all the
games that the community will keep developing and releasing with it.
2020-01-01 11:16:22 +01:00

137 lines
5.4 KiB
C++

/*************************************************************************/
/* spatial_velocity_tracker.cpp */
/*************************************************************************/
/* This file is part of: */
/* GODOT ENGINE */
/* https://godotengine.org */
/*************************************************************************/
/* Copyright (c) 2007-2020 Juan Linietsky, Ariel Manzur. */
/* Copyright (c) 2014-2020 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. */
/*************************************************************************/
#include "spatial_velocity_tracker.h"
#include "core/engine.h"
void SpatialVelocityTracker::set_track_physics_step(bool p_track_physics_step) {
physics_step = p_track_physics_step;
}
bool SpatialVelocityTracker::is_tracking_physics_step() const {
return physics_step;
}
void SpatialVelocityTracker::update_position(const Vector3 &p_position) {
PositionHistory ph;
ph.position = p_position;
if (physics_step) {
ph.frame = Engine::get_singleton()->get_physics_frames();
} else {
ph.frame = Engine::get_singleton()->get_idle_frame_ticks();
}
if (position_history_len == 0 || position_history[0].frame != ph.frame) { //in same frame, use latest
position_history_len = MIN(position_history.size(), position_history_len + 1);
for (int i = position_history_len - 1; i > 0; i--) {
position_history.write[i] = position_history[i - 1];
}
}
position_history.write[0] = ph;
}
Vector3 SpatialVelocityTracker::get_tracked_linear_velocity() const {
Vector3 linear_velocity;
float max_time = 1 / 5.0; //maximum time to interpolate a velocity
Vector3 distance_accum;
float time_accum = 0.0;
float base_time = 0.0;
if (position_history_len) {
if (physics_step) {
uint64_t base = Engine::get_singleton()->get_physics_frames();
base_time = float(base - position_history[0].frame) / Engine::get_singleton()->get_iterations_per_second();
} else {
uint64_t base = Engine::get_singleton()->get_idle_frame_ticks();
base_time = double(base - position_history[0].frame) / 1000000.0;
}
}
for (int i = 0; i < position_history_len - 1; i++) {
float delta = 0.0;
uint64_t diff = position_history[i].frame - position_history[i + 1].frame;
Vector3 distance = position_history[i].position - position_history[i + 1].position;
if (physics_step) {
delta = float(diff) / Engine::get_singleton()->get_iterations_per_second();
} else {
delta = double(diff) / 1000000.0;
}
if (base_time + time_accum + delta > max_time)
break;
distance_accum += distance;
time_accum += delta;
}
if (time_accum) {
linear_velocity = distance_accum / time_accum;
}
return linear_velocity;
}
void SpatialVelocityTracker::reset(const Vector3 &p_new_pos) {
PositionHistory ph;
ph.position = p_new_pos;
if (physics_step) {
ph.frame = Engine::get_singleton()->get_physics_frames();
} else {
ph.frame = Engine::get_singleton()->get_idle_frame_ticks();
}
position_history.write[0] = ph;
position_history_len = 1;
}
void SpatialVelocityTracker::_bind_methods() {
ClassDB::bind_method(D_METHOD("set_track_physics_step", "enable"), &SpatialVelocityTracker::set_track_physics_step);
ClassDB::bind_method(D_METHOD("is_tracking_physics_step"), &SpatialVelocityTracker::is_tracking_physics_step);
ClassDB::bind_method(D_METHOD("update_position", "position"), &SpatialVelocityTracker::update_position);
ClassDB::bind_method(D_METHOD("get_tracked_linear_velocity"), &SpatialVelocityTracker::get_tracked_linear_velocity);
ClassDB::bind_method(D_METHOD("reset", "position"), &SpatialVelocityTracker::reset);
ADD_PROPERTY(PropertyInfo(Variant::BOOL, "track_physics_step"), "set_track_physics_step", "is_tracking_physics_step");
}
SpatialVelocityTracker::SpatialVelocityTracker() {
position_history.resize(4); // should be configurable
position_history_len = 0;
physics_step = false;
}