Mirrored_Repos/veloren
1
0
Fork 0
mirror of https://gitlab.com/veloren/veloren.git synced 2024-08-30 18:12:32 +00:00
Code Issues Packages Projects Releases Wiki Activity

fmt and prepare a better unit-test framework for pyhiscs run tests

Browse Source 
Note: i added an if to check that we dont divide by 0 in revert_fak
This commit is contained in:
Marcel Märtens 2022-08-01 17:33:59 +02:00
parent 2d73375ff3
commit 34c5682485
1 changed files with 197 additions and 89 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

286
common/systems/tests/phys/basic.rs
View File

@ -295,117 +295,225 @@ fn cant_run_during_fall() -> Result<(), Box<dyn Error>> {
Ok(())
}
// The problem with old_vec is that we cant start with 0.0 0.0 0.0 as it will make the first tick different on all examples
fn mass_c() -> (f64, f64) {
let mass = 1.0;
let air_friction_co = 0.9_f64;
let air_friction_area = 0.75_f64;
let air_density = 1.225_f64;
let c = air_friction_co * air_friction_area * 0.5 * air_density * mass;
(mass, c)
}
fn test_run_helper(
tps: u32,
start_vel: f64,
start_pos: f64,
test_series: Vec<(/* acc */ f64, /* duration */ f64)>,
) -> (f64, f64) {
let dt = 1.0 / tps as f64;
let (mass, c) = mass_c();
println!("");
println!("dt: {:0>4.4} - mass: {:0>4.4} - c: {:0>4.4}", dt, mass, c);
let (mut vel, mut pos) = (start_vel, start_pos);
let mut i = 0;
for (move_dir, duration) in test_series {
let count = (duration / dt).round() as usize;
println!("move_dir: {:0>4.4}", move_dir);
for _ in 0..count {
(vel, pos) = acc_with_frict_tick(i, move_dir, vel, pos, dt);
i += 1;
}
}
(vel, pos)
}
macro_rules! veriy_diffs {
($vel1:expr, $pos1:expr, $vel2:expr, $pos2:expr) => {
let vel_diff = ($vel2 - $vel1).abs();
let pos_diff = ($pos2 - $pos1).abs();
println!("vel_diff: {:4.4}, pos_diff: {:4.4}", vel_diff, pos_diff);
assert_relative_eq!(vel_diff, 0.0, epsilon = EPSILON as f64);
assert_relative_eq!(pos_diff, 0.0, epsilon = EPSILON as f64);
};
}
/// ROLLING_FRICTION_FORCE + AIR_FRICTION_FORCE + TILT_FRICT_FORCE + ACCEL_FORCE
/// = TOTAL_FORCE
///
/// TILT_FRICT_FORCE = 0.0
/// TOTAL_FORCE = depends on char = const
/// ACCEL_FORCE = TOTAL_FORCE - ROLLING_FRICTION_FORCE - AIR_FRICTION_FORCE
/// ACCEL = ACCEL_FORCE / MASS
///
/// ROLLING_FRICTION_FORCE => Indepent of vel
/// AIR_FRICTION_FORCE => propotional to vel²
///
/// https://www.energie-lexikon.info/fahrwiderstand.html
/// https://www.energie-lexikon.info/reibung.html
/// https://sciencing.com/calculate-force-friction-6454395.html
/// https://www.leifiphysik.de/mechanik/reibung-und-fortbewegung
fn acc_with_frict_tick(i: usize, move_dir: f64, vel: f64, pos: f64, dt: f64) -> (f64, f64) {
let (mass, c) = mass_c();
const MAX_ACC: f64 = 9.2;
let acc = MAX_ACC * move_dir; // btw: cant accelerate faster than gravity on foot
let old_vel = vel;
// controller
// I know what you think, wtf, yep: https://math.stackexchange.com/questions/1929436/line-integral-of-force-of-air-resistanc
// basically an integral of the air resistance formula which scales with v^2
// transformed with an ODE.
// terminal velocity equals the maximum velocity that can be reached by acc
// alone
let vel_t = (mass * acc.abs() / c).sqrt();
let _vel_tm = (mass * MAX_ACC / c).sqrt();
// if our old_vel is bigger than vel_t we can use `coth(x) = 1/tanh(x)` and
// `acoth(x) = atanh(1/x)`
let revert_fak = if vel_t != 0.0 {
old_vel / vel_t
} else {
1337.0
};
let vel = if revert_fak.abs() >= 1.0 {
vel_t / ((1.0 / revert_fak).atanh() + acc.signum() * (c * acc.abs()).sqrt() * dt).tanh()
} else {
vel_t * ((revert_fak).atanh() + acc.signum() * (c * acc.abs()).sqrt() * dt).tanh()
};
//physics
let distance_last = mass / c * (((old_vel * (c / acc / mass).sqrt()).atanh()).cosh()).ln();
let distance = mass / c
* (((old_vel * (c / acc / mass).sqrt()).atanh() + dt * (c * acc / mass).sqrt()).cosh())
.ln();
let diff = distance - distance_last;
let diff = if !diff.is_finite() { 0.0 } else { diff };
let pos = pos + diff;
let ending = ((i + 1) as f64 * dt * 100.0).round() as i64;
let line = format!(
"[{:0>2.2}]: acc: {:0>5.4}, revert_fak: {:0>4.4}, vel: {:0>4.4}, dist: \
{:0>7.4}, pos: {:0>7.4}",
(i + 1) as f64 * dt,
acc,
revert_fak,
vel,
distance,
pos
);
if ending % 10 != 0 {
println!("\x1b[94m{}\x1b[0m", line)
} else {
println!("{}", line)
}
(vel, pos)
}
#[test]
fn physics_theory() -> Result<(), Box<dyn Error>> {
let tick = |i: usize, move_dir: f64, acc: f64, vel: f64, pos: f64, dt: f64| {
/*
ROLLING_FRICTION_FORCE + AIR_FRICTION_FORCE + TILT_FRICT_FORCE + ACCEL_FORCE = TOTAL_FORCE
fn physics_constant_walk() {
let (vel_05, pos_05) = test_run_helper(20, 0.0, 0.0, vec![(0.5, 0.5)]);
let (vel_10, pos_10) = test_run_helper(10, 0.0, 0.0, vec![(0.5, 0.5)]);
TILT_FRICT_FORCE = 0.0
TOTAL_FORCE = depends on char = const
ACCEL_FORCE = TOTAL_FORCE - ROLLING_FRICTION_FORCE - AIR_FRICTION_FORCE
ACCEL = ACCEL_FORCE / MASS
veriy_diffs!(vel_05, pos_05, vel_10, pos_10);
}
ROLLING_FRICTION_FORCE => Indepent of vel
AIR_FRICTION_FORCE => propotional to vel²
https://www.energie-lexikon.info/fahrwiderstand.html
#[test]
fn physics_constant_stay() {
let (vel_05, pos_05) = test_run_helper(20, 0.0, 0.0, vec![(0.0, 1.0)]);
let (vel_10, pos_10) = test_run_helper(10, 0.0, 0.0, vec![(0.0, 1.0)]);
https://www.energie-lexikon.info/reibung.html
veriy_diffs!(vel_05, pos_05, vel_10, pos_10);
assert_relative_eq!(vel_05, 0.0, epsilon = EPSILON as f64);
assert_relative_eq!(pos_05, 0.0, epsilon = EPSILON as f64);
}
https://sciencing.com/calculate-force-friction-6454395.html
#[test]
fn physics_walk_run_b() {
let (vel_05, pos_05) = test_run_helper(20, 0.0, 0.0, vec![(0.5, 2.0), (1.0, 2.0)]);
let (vel_10, pos_10) = test_run_helper(10, 0.0, 0.0, vec![(0.5, 2.0), (1.0, 2.0)]);
https://www.leifiphysik.de/mechanik/reibung-und-fortbewegung
veriy_diffs!(vel_05, pos_05, vel_10, pos_10);
}
#[test]
fn physics_walk_run_walk() {
let (vel_05, pos_05) = test_run_helper(20, 0.0, 0.0, vec![(0.5, 2.0), (1.0, 3.0), (0.5, 0.5)]);
let (vel_10, pos_10) = test_run_helper(10, 0.0, 0.0, vec![(0.5, 2.0), (1.0, 3.0), (0.5, 0.5)]);
*/
veriy_diffs!(vel_05, pos_05, vel_10, pos_10);
}
let mass = 1.0;
#[test]
fn physics_run_walk_b() {
let (vel_05, pos_05) = test_run_helper(20, 0.0, 0.0, vec![(1.0, 0.5), (0.5, 0.5)]);
let (vel_10, pos_10) = test_run_helper(10, 0.0, 0.0, vec![(1.0, 0.5), (0.5, 0.5)]);
let air_friction_co = 0.9_f64;
let air_friction_area = 0.75_f64;
let air_density = 1.225_f64;
let c = air_friction_co * air_friction_area * 0.5 * air_density * mass ;
veriy_diffs!(vel_05, pos_05, vel_10, pos_10);
}
const MAX_ACC: f64 = 9.2;
let acc = MAX_ACC * move_dir; // btw: cant accelerate faster than gravity on foot
let old_vel = vel;
#[test]
fn physics_runlong_walk_b() {
let (vel_05, pos_05) = test_run_helper(20, 0.0, 0.0, vec![(1.0, 3.0), (0.5, 0.5)]);
let (vel_10, pos_10) = test_run_helper(10, 0.0, 0.0, vec![(1.0, 3.0), (0.5, 0.5)]);
// controller
// I know what you think, wtf, yep: https://math.stackexchange.com/questions/1929436/line-integral-of-force-of-air-resistanc
// basically an integral of the air resistance formula which scales with v^2 transformed with an ODE.
veriy_diffs!(vel_05, pos_05, vel_10, pos_10);
}
// terminal velocity equals the maximum velocity that can be reached by acc alone
let vel_t = (mass * acc.abs() / c ).sqrt();
let _vel_tm = (mass * MAX_ACC / c ).sqrt();
#[test]
fn physics_walk_stop() {
let (vel_05, pos_05) = test_run_helper(20, 0.0, 0.0, vec![(0.5, 0.5), (0.0, 0.5)]);
let (vel_10, pos_10) = test_run_helper(10, 0.0, 0.0, vec![(0.5, 0.5), (0.0, 0.5)]);
// if our old_vel is bigger than vel_t we can use `coth(x) = 1/tanh(x)` and `acoth(x) = atanh(1/x)`
let revert_fak = old_vel / vel_t ;
let vel = if revert_fak.abs() >= 1.0 {
vel_t / ( ( 1.0 / revert_fak).atanh() + acc.signum() * (c * acc.abs()).sqrt() * dt ).tanh()
} else {
vel_t * ( ( revert_fak ).atanh() + acc.signum() * (c * acc.abs()).sqrt() * dt ).tanh()
};
veriy_diffs!(vel_05, pos_05, vel_10, pos_10);
}
//physics
let distance_last = mass / c * ( ( ( old_vel * (c/acc / mass).sqrt()).atanh() ).cosh() ).ln();
let distance = mass / c * ( ( ( old_vel * (c/acc / mass).sqrt()).atanh() + dt* (c * acc / mass).sqrt()).cosh() ).ln();
let diff = distance - distance_last;
let diff = if !diff.is_finite() {
0.0
} else {
diff
};
#[test]
fn physics_runlong_stop() {
let (vel_05, pos_05) = test_run_helper(20, 0.0, 0.0, vec![(1.0, 3.0), (0.0, 0.5)]);
let (vel_10, pos_10) = test_run_helper(10, 0.0, 0.0, vec![(1.0, 3.0), (0.0, 0.5)]);
let pos = pos + diff;
veriy_diffs!(vel_05, pos_05, vel_10, pos_10);
}
#[test]
fn physics_stop_walk() {
let (vel_05, pos_05) = test_run_helper(20, 0.0, 0.0, vec![(0.0, 0.5), (0.5, 0.5)]);
let (vel_10, pos_10) = test_run_helper(10, 0.0, 0.0, vec![(0.0, 0.5), (0.5, 0.5)]);
let ending = ((i+1) as f64 *dt * 10.0).round() as i64;
let line = format!("[{:0>2.1}]: move_dir: {:0>1.1}, acc: {:0>4.4}, revert_fak: {:0>4.4}, vel: {:0>4.4}, dist: {:0>7.4}, dist: {:0>7.4}, pos: {:0>7.4}, c: {:0>4.4}", (i+1) as f64 *dt, move_dir, acc, revert_fak, vel, distance_last, distance, pos, c);
if ending % 10 == 0 {
println!("\x1b[91m{}\x1b[0m", line)
} else if ending % 2 != 0 {
println!("\x1b[94m{}\x1b[0m", line)
} else {
println!("{}", line)
}
veriy_diffs!(vel_05, pos_05, vel_10, pos_10);
}
(acc, vel, pos)
};
#[test]
fn physics_run_walkback() {
let (vel_05, pos_05) = test_run_helper(20, 0.0, 0.0, vec![(0.5, 0.5), (-0.5, 0.5)]);
let (vel_10, pos_10) = test_run_helper(10, 0.0, 0.0, vec![(0.5, 0.5), (-0.5, 0.5)]);
let test_run = |tps: u32| {
let dt = 1.0 / tps as f64;
println!("");
println!("dt: {}", dt);
let (mut acc, mut vel, mut pos) = (0.0, 0.0, 0.0);
let mut i = 0;
for _ in 0..tps*2 {
(acc, vel, pos) = tick(i, 1.0, acc, vel, pos, dt);
i += 1;
}
for _ in 0..tps*2 {
(acc, vel, pos) = tick(i, 0.1, acc, vel, pos, dt);
i += 1;
}
for _ in 0..tps {
(acc, vel, pos) = tick(i, 1.0, acc, vel, pos, dt);
i += 1;
}
(vel, pos)
};
veriy_diffs!(vel_05, pos_05, vel_10, pos_10);
}
let (vel_final_01, pos_final_01) = test_run(10);
let (vel_final_02, pos_final_02) = test_run(5);
let (vel_final_10, pos_final_10) = test_run(1);
#[test]
fn physics_runlong_walkback_stop() {
let (vel_05, pos_05) = test_run_helper(20, 0.0, 0.0, vec![(1.0, 3.0), (-0.5, 0.5), (0.0, 0.5)]);
let (vel_10, pos_10) = test_run_helper(10, 0.0, 0.0, vec![(1.0, 3.0), (-0.5, 0.5), (0.0, 0.5)]);
let vel_diff = (vel_final_02 - vel_final_01).abs();
let pos_diff = (pos_final_02 - pos_final_01).abs();
println!("[ #1 ] vel_diff: {:4.4}, pos_diff: {:4.4}", vel_diff, pos_diff);
veriy_diffs!(vel_05, pos_05, vel_10, pos_10);
}
let vel_diff = (vel_final_10 - vel_final_01).abs();
let pos_diff = (pos_final_10 - pos_final_01).abs();
println!("[ #2 ] vel_diff: {:4.4}, pos_diff: {:4.4}", vel_diff, pos_diff);
#[test]
fn physics_walkback_stop() {
let (vel_05, pos_05) = test_run_helper(20, 0.0, 0.0, vec![(-0.5, 0.5), (0.0, 0.5)]);
let (vel_10, pos_10) = test_run_helper(10, 0.0, 0.0, vec![(-0.5, 0.5), (0.0, 0.5)]);
Ok(())
}
veriy_diffs!(vel_05, pos_05, vel_10, pos_10);
}
#[test]
fn physics_walkback_run() {
let (vel_05, pos_05) = test_run_helper(20, 0.0, 0.0, vec![(-0.5, 5.0), (1.0, 0.5)]);
let (vel_10, pos_10) = test_run_helper(10, 0.0, 0.0, vec![(-0.5, 5.0), (1.0, 0.5)]);
veriy_diffs!(vel_05, pos_05, vel_10, pos_10);
}