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use crate::dynamics::RigidBodySet;
use crate::geometry::{ColliderHandle, ColliderSet, ContactManifold, Shape, ShapeCastHit};
use crate::math::{Isometry, Point, Real, UnitVector, Vector};
use crate::pipeline::{QueryFilter, QueryFilterFlags, QueryPipeline};
use crate::utils;
use na::{RealField, Vector2};
use parry::bounding_volume::BoundingVolume;
use parry::math::Translation;
use parry::query::details::ShapeCastOptions;
use parry::query::{DefaultQueryDispatcher, PersistentQueryDispatcher};
#[cfg_attr(feature = "serde-serialize", derive(Serialize, Deserialize))]
#[derive(Copy, Clone, Debug, PartialEq)]
/// A length measure used for various options of a character controller.
pub enum CharacterLength {
/// The length is specified relative to some of the character shape’s size.
///
/// For example setting `CharacterAutostep::max_height` to `CharacterLength::Relative(0.1)`
/// for a shape with a height equal to 20.0 will result in a maximum step height
/// of `0.1 * 20.0 = 2.0`.
Relative(Real),
/// The length is specified as an absolute value, independent from the character shape’s size.
///
/// For example setting `CharacterAutostep::max_height` to `CharacterLength::Relative(0.1)`
/// for a shape with a height equal to 20.0 will result in a maximum step height
/// of `0.1` (the shape height is ignored in for this value).
Absolute(Real),
}
impl CharacterLength {
/// Returns `self` with its value changed by the closure `f` if `self` is the `Self::Absolute`
/// variant.
pub fn map_absolute(self, f: impl FnOnce(Real) -> Real) -> Self {
if let Self::Absolute(value) = self {
Self::Absolute(f(value))
} else {
self
}
}
/// Returns `self` with its value changed by the closure `f` if `self` is the `Self::Relative`
/// variant.
pub fn map_relative(self, f: impl FnOnce(Real) -> Real) -> Self {
if let Self::Relative(value) = self {
Self::Relative(f(value))
} else {
self
}
}
fn eval(self, value: Real) -> Real {
match self {
Self::Relative(x) => value * x,
Self::Absolute(x) => x,
}
}
}
#[derive(Debug)]
struct HitInfo {
toi: ShapeCastHit,
is_wall: bool,
is_nonslip_slope: bool,
}
/// Configuration for the auto-stepping character controller feature.
#[cfg_attr(feature = "serde-serialize", derive(Serialize, Deserialize))]
#[derive(Copy, Clone, Debug, PartialEq)]
pub struct CharacterAutostep {
/// The maximum step height a character can automatically step over.
pub max_height: CharacterLength,
/// The minimum width of free space that must be available after stepping on a stair.
pub min_width: CharacterLength,
/// Can the character automatically step over dynamic bodies too?
pub include_dynamic_bodies: bool,
}
impl Default for CharacterAutostep {
fn default() -> Self {
Self {
max_height: CharacterLength::Relative(0.25),
min_width: CharacterLength::Relative(0.5),
include_dynamic_bodies: true,
}
}
}
#[derive(Debug)]
struct HitDecomposition {
normal_part: Vector<Real>,
horizontal_tangent: Vector<Real>,
vertical_tangent: Vector<Real>,
// NOTE: we don’t store the penetration part since we don’t really need it
// for anything.
}
impl HitDecomposition {
pub fn unconstrained_slide_part(&self) -> Vector<Real> {
self.normal_part + self.horizontal_tangent + self.vertical_tangent
}
}
/// A collision between the character and its environment during its movement.
#[derive(Copy, Clone, Debug)]
pub struct CharacterCollision {
/// The collider hit by the character.
pub handle: ColliderHandle,
/// The position of the character when the collider was hit.
pub character_pos: Isometry<Real>,
/// The translation that was already applied to the character when the hit happens.
pub translation_applied: Vector<Real>,
/// The translations that was still waiting to be applied to the character when the hit happens.
pub translation_remaining: Vector<Real>,
/// Geometric information about the hit.
pub hit: ShapeCastHit,
}
/// A character controller for kinematic bodies.
#[cfg_attr(feature = "serde-serialize", derive(Serialize, Deserialize))]
#[derive(Copy, Clone, Debug)]
pub struct KinematicCharacterController {
/// The direction that goes "up". Used to determine where the floor is, and the floor’s angle.
pub up: UnitVector<Real>,
/// A small gap to preserve between the character and its surroundings.
///
/// This value should not be too large to avoid visual artifacts, but shouldn’t be too small
/// (must not be zero) to improve numerical stability of the character controller.
pub offset: CharacterLength,
/// Should the character try to slide against the floor if it hits it?
pub slide: bool,
/// Should the character automatically step over small obstacles? (disabled by default)
///
/// Note that autostepping is currently a very computationally expensive feature, so it
/// is disabled by default.
pub autostep: Option<CharacterAutostep>,
/// The maximum angle (radians) between the floor’s normal and the `up` vector that the
/// character is able to climb.
pub max_slope_climb_angle: Real,
/// The minimum angle (radians) between the floor’s normal and the `up` vector before the
/// character starts to slide down automatically.
pub min_slope_slide_angle: Real,
/// Should the character be automatically snapped to the ground if the distance between
/// the ground and its feed are smaller than the specified threshold?
pub snap_to_ground: Option<CharacterLength>,
/// Increase this number if your character appears to get stuck when sliding against surfaces.
///
/// This is a small distance applied to the movement toward the contact normals of shapes hit
/// by the character controller. This helps shape-casting not getting stuck in an always-penetrating
/// state during the sliding calculation.
///
/// This value should remain fairly small since it can introduce artificial "bumps" when sliding
/// along a flat surface.
pub normal_nudge_factor: Real,
}
impl Default for KinematicCharacterController {
fn default() -> Self {
Self {
up: Vector::y_axis(),
offset: CharacterLength::Relative(0.01),
slide: true,
autostep: None,
max_slope_climb_angle: Real::frac_pi_4(),
min_slope_slide_angle: Real::frac_pi_4(),
snap_to_ground: Some(CharacterLength::Relative(0.2)),
normal_nudge_factor: 1.0e-4,
}
}
}
/// The effective movement computed by the character controller.
pub struct EffectiveCharacterMovement {
/// The movement to apply.
pub translation: Vector<Real>,
/// Is the character touching the ground after applying `EffectiveKineamticMovement::translation`?
pub grounded: bool,
/// Is the character sliding down a slope due to slope angle being larger than `min_slope_slide_angle`?
pub is_sliding_down_slope: bool,
}
impl KinematicCharacterController {
fn check_and_fix_penetrations(&self) {
/*
// 1/ Check if the body is grounded and if there are penetrations.
let mut grounded = false;
let mut penetrating = false;
let mut contacts = vec![];
let aabb = shape
.compute_aabb(shape_pos)
.loosened(self.offset);
queries.colliders_with_aabb_intersecting_aabb(&aabb, |handle| {
// TODO: apply the filter.
if let Some(collider) = colliders.get(*handle) {
if let Ok(Some(contact)) = parry::query::contact(
&shape_pos,
shape,
collider.position(),
collider.shape(),
self.offset,
) {
contacts.push((contact, collider));
}
}
true
});
*/
}
/// Computes the possible movement for a shape.
pub fn move_shape(
&self,
dt: Real,
bodies: &RigidBodySet,
colliders: &ColliderSet,
queries: &QueryPipeline,
character_shape: &dyn Shape,
character_pos: &Isometry<Real>,
desired_translation: Vector<Real>,
filter: QueryFilter,
mut events: impl FnMut(CharacterCollision),
) -> EffectiveCharacterMovement {
let mut result = EffectiveCharacterMovement {
translation: Vector::zeros(),
grounded: false,
is_sliding_down_slope: false,
};
let dims = self.compute_dims(character_shape);
// 1. Check and fix penetrations.
self.check_and_fix_penetrations();
let mut translation_remaining = desired_translation;
let grounded_at_starting_pos = self.detect_grounded_status_and_apply_friction(
dt,
bodies,
colliders,
queries,
character_shape,
character_pos,
&dims,
filter,
None,
None,
);
let mut max_iters = 20;
let mut kinematic_friction_translation = Vector::zeros();
let offset = self.offset.eval(dims.y);
while let Some((translation_dir, translation_dist)) =
UnitVector::try_new_and_get(translation_remaining, 1.0e-5)
{
if max_iters == 0 {
break;
} else {
max_iters -= 1;
}
// 2. Cast towards the movement direction.
if let Some((handle, hit)) = queries.cast_shape(
bodies,
colliders,
&(Translation::from(result.translation) * character_pos),
&translation_dir,
character_shape,
ShapeCastOptions {
target_distance: offset,
stop_at_penetration: false,
max_time_of_impact: translation_dist,
compute_impact_geometry_on_penetration: true,
},
filter,
) {
// We hit something, compute and apply the allowed interference-free translation.
let allowed_dist = hit.time_of_impact;
let allowed_translation = *translation_dir * allowed_dist;
result.translation += allowed_translation;
translation_remaining -= allowed_translation;
events(CharacterCollision {
handle,
character_pos: Translation::from(result.translation) * character_pos,
translation_applied: result.translation,
translation_remaining,
hit,
});
let hit_info = self.compute_hit_info(hit);
// Try to go upstairs.
if !self.handle_stairs(
bodies,
colliders,
queries,
character_shape,
&(Translation::from(result.translation) * character_pos),
&dims,
filter,
handle,
&hit_info,
&mut translation_remaining,
&mut result,
) {
// No stairs, try to move along slopes.
translation_remaining = self.handle_slopes(
&hit_info,
&desired_translation,
&translation_remaining,
self.normal_nudge_factor,
&mut result,
);
}
} else {
// No interference along the path.
result.translation += translation_remaining;
translation_remaining.fill(0.0);
break;
}
result.grounded = self.detect_grounded_status_and_apply_friction(
dt,
bodies,
colliders,
queries,
character_shape,
&(Translation::from(result.translation) * character_pos),
&dims,
filter,
Some(&mut kinematic_friction_translation),
Some(&mut translation_remaining),
);
if !self.slide {
break;
}
}
// If needed, and if we are not already grounded, snap to the ground.
if grounded_at_starting_pos {
self.snap_to_ground(
bodies,
colliders,
queries,
character_shape,
&(Translation::from(result.translation) * character_pos),
&dims,
filter,
&mut result,
);
}
// Return the result.
result
}
fn snap_to_ground(
&self,
bodies: &RigidBodySet,
colliders: &ColliderSet,
queries: &QueryPipeline,
character_shape: &dyn Shape,
character_pos: &Isometry<Real>,
dims: &Vector2<Real>,
filter: QueryFilter,
result: &mut EffectiveCharacterMovement,
) -> Option<(ColliderHandle, ShapeCastHit)> {
if let Some(snap_distance) = self.snap_to_ground {
if result.translation.dot(&self.up) < -1.0e-5 {
let snap_distance = snap_distance.eval(dims.y);
let offset = self.offset.eval(dims.y);
if let Some((hit_handle, hit)) = queries.cast_shape(
bodies,
colliders,
character_pos,
&-self.up,
character_shape,
ShapeCastOptions {
target_distance: offset,
stop_at_penetration: false,
max_time_of_impact: snap_distance,
compute_impact_geometry_on_penetration: true,
},
filter,
) {
// Apply the snap.
result.translation -= *self.up * hit.time_of_impact;
result.grounded = true;
return Some((hit_handle, hit));
}
}
}
None
}
fn predict_ground(&self, up_extends: Real) -> Real {
self.offset.eval(up_extends) * 1.1
}
fn detect_grounded_status_and_apply_friction(
&self,
dt: Real,
bodies: &RigidBodySet,
colliders: &ColliderSet,
queries: &QueryPipeline,
character_shape: &dyn Shape,
character_pos: &Isometry<Real>,
dims: &Vector2<Real>,
filter: QueryFilter,
mut kinematic_friction_translation: Option<&mut Vector<Real>>,
mut translation_remaining: Option<&mut Vector<Real>>,
) -> bool {
let prediction = self.predict_ground(dims.y);
// TODO: allow custom dispatchers.
let dispatcher = DefaultQueryDispatcher;
let mut manifolds: Vec<ContactManifold> = vec![];
let character_aabb = character_shape
.compute_aabb(character_pos)
.loosened(prediction);
let mut grounded = false;
queries.colliders_with_aabb_intersecting_aabb(&character_aabb, |handle| {
if let Some(collider) = colliders.get(*handle) {
if filter.test(bodies, *handle, collider) {
manifolds.clear();
let pos12 = character_pos.inv_mul(collider.position());
let _ = dispatcher.contact_manifolds(
&pos12,
character_shape,
collider.shape(),
prediction,
&mut manifolds,
&mut None,
);
if let (Some(kinematic_friction_translation), Some(translation_remaining)) = (
kinematic_friction_translation.as_deref_mut(),
translation_remaining.as_deref_mut(),
) {
let init_kinematic_friction_translation = *kinematic_friction_translation;
let kinematic_parent = collider
.parent
.and_then(|p| bodies.get(p.handle))
.filter(|rb| rb.is_kinematic());
for m in &manifolds {
if self.is_grounded_at_contact_manifold(m, character_pos, dims) {
grounded = true;
}
if let Some(kinematic_parent) = kinematic_parent {
let mut num_active_contacts = 0;
let mut manifold_center = Point::origin();
let normal = -(character_pos * m.local_n1);
for contact in &m.points {
if contact.dist <= prediction {
num_active_contacts += 1;
let contact_point = collider.position() * contact.local_p2;
let target_vel =
kinematic_parent.velocity_at_point(&contact_point);
let normal_target_mvt = target_vel.dot(&normal) * dt;
let normal_current_mvt = translation_remaining.dot(&normal);
manifold_center += contact_point.coords;
*translation_remaining +=
normal * (normal_target_mvt - normal_current_mvt);
}
}
if num_active_contacts > 0 {
let target_vel = kinematic_parent.velocity_at_point(
&(manifold_center / num_active_contacts as Real),
);
let tangent_platform_mvt =
(target_vel - normal * target_vel.dot(&normal)) * dt;
kinematic_friction_translation.zip_apply(
&tangent_platform_mvt,
|y, x| {
if x.abs() > (*y).abs() {
*y = x;
}
},
);
}
}
}
*translation_remaining +=
*kinematic_friction_translation - init_kinematic_friction_translation;
} else {
for m in &manifolds {
if self.is_grounded_at_contact_manifold(m, character_pos, dims) {
grounded = true;
return false; // We can stop the search early.
}
}
}
}
}
true
});
grounded
}
fn is_grounded_at_contact_manifold(
&self,
manifold: &ContactManifold,
character_pos: &Isometry<Real>,
dims: &Vector2<Real>,
) -> bool {
let normal = -(character_pos * manifold.local_n1);
if normal.dot(&self.up) >= 1.0e-5 {
let prediction = self.predict_ground(dims.y);
for contact in &manifold.points {
if contact.dist <= prediction {
return true;
}
}
}
false
}
fn handle_slopes(
&self,
hit: &HitInfo,
movement_input: &Vector<Real>,
translation_remaining: &Vector<Real>,
normal_nudge_factor: Real,
result: &mut EffectiveCharacterMovement,
) -> Vector<Real> {
let [_vertical_input, horizontal_input] = self.split_into_components(movement_input);
let horiz_input_decomp = self.decompose_hit(&horizontal_input, &hit.toi);
let input_decomp = self.decompose_hit(movement_input, &hit.toi);
let decomp = self.decompose_hit(translation_remaining, &hit.toi);
// An object is trying to slip if the tangential movement induced by its vertical movement
// points downward.
let slipping_intent = self.up.dot(&horiz_input_decomp.vertical_tangent) < 0.0;
let slipping = self.up.dot(&decomp.vertical_tangent) < 0.0;
// An object is trying to climb if its indirect vertical motion points upward.
let climbing_intent = self.up.dot(&input_decomp.vertical_tangent) > 0.0;
let climbing = self.up.dot(&decomp.vertical_tangent) > 0.0;
let allowed_movement = if hit.is_wall && climbing && !climbing_intent {
// Can’t climb the slope, remove the vertical tangent motion induced by the forward motion.
decomp.horizontal_tangent + decomp.normal_part
} else if hit.is_nonslip_slope && slipping && !slipping_intent {
// Prevent the vertical movement from sliding down.
decomp.horizontal_tangent + decomp.normal_part
} else {
// Let it slide (including climbing the slope).
result.is_sliding_down_slope = true;
decomp.unconstrained_slide_part()
};
allowed_movement + *hit.toi.normal1 * normal_nudge_factor
}
fn split_into_components(&self, translation: &Vector<Real>) -> [Vector<Real>; 2] {
let vertical_translation = *self.up * (self.up.dot(translation));
let horizontal_translation = *translation - vertical_translation;
[vertical_translation, horizontal_translation]
}
fn compute_hit_info(&self, toi: ShapeCastHit) -> HitInfo {
let angle_with_floor = self.up.angle(&toi.normal1);
let is_ceiling = self.up.dot(&toi.normal1) < 0.0;
let is_wall = angle_with_floor >= self.max_slope_climb_angle && !is_ceiling;
let is_nonslip_slope = angle_with_floor <= self.min_slope_slide_angle;
HitInfo {
toi,
is_wall,
is_nonslip_slope,
}
}
fn decompose_hit(&self, translation: &Vector<Real>, hit: &ShapeCastHit) -> HitDecomposition {
let dist_to_surface = translation.dot(&hit.normal1);
let normal_part;
let penetration_part;
if dist_to_surface < 0.0 {
normal_part = Vector::zeros();
penetration_part = dist_to_surface * *hit.normal1;
} else {
penetration_part = Vector::zeros();
normal_part = dist_to_surface * *hit.normal1;
}
let tangent = translation - normal_part - penetration_part;
#[cfg(feature = "dim3")]
let horizontal_tangent_dir = hit.normal1.cross(&self.up);
#[cfg(feature = "dim2")]
let horizontal_tangent_dir = Vector::zeros();
let horizontal_tangent_dir = horizontal_tangent_dir
.try_normalize(1.0e-5)
.unwrap_or_default();
let horizontal_tangent = tangent.dot(&horizontal_tangent_dir) * horizontal_tangent_dir;
let vertical_tangent = tangent - horizontal_tangent;
HitDecomposition {
normal_part,
horizontal_tangent,
vertical_tangent,
}
}
fn compute_dims(&self, character_shape: &dyn Shape) -> Vector2<Real> {
let extents = character_shape.compute_local_aabb().extents();
let up_extent = extents.dot(&self.up.abs());
let side_extent = (extents - (*self.up).abs() * up_extent).norm();
Vector2::new(side_extent, up_extent)
}
fn handle_stairs(
&self,
bodies: &RigidBodySet,
colliders: &ColliderSet,
queries: &QueryPipeline,
character_shape: &dyn Shape,
character_pos: &Isometry<Real>,
dims: &Vector2<Real>,
mut filter: QueryFilter,
stair_handle: ColliderHandle,
hit: &HitInfo,
translation_remaining: &mut Vector<Real>,
result: &mut EffectiveCharacterMovement,
) -> bool {
let Some(autostep) = self.autostep else {
return false;
};
// Only try to autostep on walls.
if !hit.is_wall {
return false;
}
let offset = self.offset.eval(dims.y);
let min_width = autostep.min_width.eval(dims.x) + offset;
let max_height = autostep.max_height.eval(dims.y) + offset;
if !autostep.include_dynamic_bodies {
if colliders
.get(stair_handle)
.and_then(|co| co.parent)
.and_then(|p| bodies.get(p.handle))
.map(|b| b.is_dynamic())
== Some(true)
{
// The "stair" is a dynamic body, which the user wants to ignore.
return false;
}
filter.flags |= QueryFilterFlags::EXCLUDE_DYNAMIC;
}
let shifted_character_pos = Translation::from(*self.up * max_height) * character_pos;
let Some(horizontal_dir) = (*translation_remaining
- *self.up * translation_remaining.dot(&self.up))
.try_normalize(1.0e-5) else {
return false;
};
if queries
.cast_shape(
bodies,
colliders,
character_pos,
&self.up,
character_shape,
ShapeCastOptions {
target_distance: offset,
stop_at_penetration: false,
max_time_of_impact: max_height,
compute_impact_geometry_on_penetration: true,
},
filter,
)
.is_some()
{
// We can’t go up.
return false;
}
if queries
.cast_shape(
bodies,
colliders,
&shifted_character_pos,
&horizontal_dir,
character_shape,
ShapeCastOptions {
target_distance: offset,
stop_at_penetration: false,
max_time_of_impact: min_width,
compute_impact_geometry_on_penetration: true,
},
filter,
)
.is_some()
{
// We don’t have enough room on the stair to stay on it.
return false;
}
// Check that we are not getting into a ramp that is too steep
// after stepping.
if let Some((_, hit)) = queries.cast_shape(
bodies,
colliders,
&(Translation::from(horizontal_dir * min_width) * shifted_character_pos),
&-self.up,
character_shape,
ShapeCastOptions {
target_distance: offset,
stop_at_penetration: false,
max_time_of_impact: max_height,
compute_impact_geometry_on_penetration: true,
},
filter,
) {
let [vertical_slope_translation, horizontal_slope_translation] = self
.split_into_components(translation_remaining)
.map(|remaining| subtract_hit(remaining, &hit));
let slope_translation = horizontal_slope_translation + vertical_slope_translation;
let angle_with_floor = self.up.angle(&hit.normal1);
let climbing = self.up.dot(&slope_translation) >= 0.0;
if climbing && angle_with_floor > self.max_slope_climb_angle {
return false; // The target ramp is too steep.
}
}
// We can step, we need to find the actual step height.
let step_height = max_height
- queries
.cast_shape(
bodies,
colliders,
&(Translation::from(horizontal_dir * min_width) * shifted_character_pos),
&-self.up,
character_shape,
ShapeCastOptions {
target_distance: offset,
stop_at_penetration: false,
max_time_of_impact: max_height,
compute_impact_geometry_on_penetration: true,
},
filter,
)
.map(|hit| hit.1.time_of_impact)
.unwrap_or(max_height);
// Remove the step height from the vertical part of the self.
let step = *self.up * step_height;
*translation_remaining -= step;
// Advance the collider on the step horizontally, to make sure further
// movement won’t just get stuck on its edge.
let horizontal_nudge =
horizontal_dir * horizontal_dir.dot(translation_remaining).min(min_width);
*translation_remaining -= horizontal_nudge;
result.translation += step + horizontal_nudge;
true
}
/// For a given collision between a character and its environment, this method will apply
/// impulses to the rigid-bodies surrounding the character shape at the time of the collision.
/// Note that the impulse calculation is only approximate as it is not based on a global
/// constraints resolution scheme.
pub fn solve_character_collision_impulses(
&self,
dt: Real,
bodies: &mut RigidBodySet,
colliders: &ColliderSet,
queries: &QueryPipeline,
character_shape: &dyn Shape,
character_mass: Real,
collision: &CharacterCollision,
filter: QueryFilter,
) {
let extents = character_shape.compute_local_aabb().extents();
let up_extent = extents.dot(&self.up.abs());
let movement_to_transfer =
*collision.hit.normal1 * collision.translation_remaining.dot(&collision.hit.normal1);
let prediction = self.predict_ground(up_extent);
// TODO: allow custom dispatchers.
let dispatcher = DefaultQueryDispatcher;
let mut manifolds: Vec<ContactManifold> = vec![];
let character_aabb = character_shape
.compute_aabb(&collision.character_pos)
.loosened(prediction);
queries.colliders_with_aabb_intersecting_aabb(&character_aabb, |handle| {
if let Some(collider) = colliders.get(*handle) {
if let Some(parent) = collider.parent {
if filter.test(bodies, *handle, collider) {
if let Some(body) = bodies.get(parent.handle) {
if body.is_dynamic() {
manifolds.clear();
let pos12 = collision.character_pos.inv_mul(collider.position());
let prev_manifolds_len = manifolds.len();
let _ = dispatcher.contact_manifolds(
&pos12,
character_shape,
collider.shape(),
prediction,
&mut manifolds,
&mut None,
);
for m in &mut manifolds[prev_manifolds_len..] {
m.data.rigid_body2 = Some(parent.handle);
m.data.normal = collision.character_pos * m.local_n1;
}
}
}
}
}
}
true
});
let velocity_to_transfer = movement_to_transfer * utils::inv(dt);
for manifold in &manifolds {
let body_handle = manifold.data.rigid_body2.unwrap();
let body = &mut bodies[body_handle];
for pt in &manifold.points {
if pt.dist <= prediction {
let body_mass = body.mass();
let contact_point = body.position() * pt.local_p2;
let delta_vel_per_contact = (velocity_to_transfer
- body.velocity_at_point(&contact_point))
.dot(&manifold.data.normal);
let mass_ratio = body_mass * character_mass / (body_mass + character_mass);
body.apply_impulse_at_point(
manifold.data.normal * delta_vel_per_contact.max(0.0) * mass_ratio,
contact_point,
true,
);
}
}
}
}
}
fn subtract_hit(translation: Vector<Real>, hit: &ShapeCastHit) -> Vector<Real> {
let surface_correction = (-translation).dot(&hit.normal1).max(0.0);
// This fixes some instances of moving through walls
let surface_correction = surface_correction * (1.0 + 1.0e-5);
translation + *hit.normal1 * surface_correction
}