TheCloud/panda3d
1
0
Fork 0
mirror of https://github.com/panda3d/panda3d.git synced 2025-09-29 08:15:18 -04:00
Code Issues Packages Projects Releases Wiki Activity

collide: Implement respect-prev-transform for capsule-into-poly

Browse Source 
It's not perfect by any means, but it's better than nothing, and should prevent capsules from flying through walls.
This commit is contained in:
rdb 2021-01-12 15:54:42 +01:00
parent 3f08781eac
commit 6e168c2bc4
1 changed files with 53 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

55
panda/src/collide/collisionPolygon.cxx
View File

@ -889,7 +889,8 @@ test_intersection_from_capsule(const CollisionEntry &entry) const {
const CollisionCapsule *capsule;
DCAST_INTO_R(capsule, entry.get_from(), nullptr);
const LMatrix4 &wrt_mat = entry.get_wrt_mat();
CPT(TransformState) wrt_space = entry.get_wrt_space();
const LMatrix4 &wrt_mat = wrt_space->get_mat();
LMatrix4 plane_mat = wrt_mat * _to_2d_mat;
LPoint3 from_a = capsule->get_point_a() * plane_mat;
@ -905,7 +906,57 @@ test_intersection_from_capsule(const CollisionEntry &entry) const {
// Yes, so calculate the distance of the closest point.
PN_stdfloat dist = min(cabs(from_a[1]), cabs(from_b[1]));
if (dist * dist > from_radius_sq) {
return nullptr;
// Not currently colliding. Did the capsule travel into the plane?
if (from_a[1] < 0 || !entry.get_respect_prev_transform()) {
return nullptr;
}
CPT(TransformState) wrt_prev_space = entry.get_wrt_prev_space();
if (wrt_prev_space == wrt_space) {
return nullptr;
}
// Note that we only check for a sphere at the center, since we don't
// know whether the capsule has undergone any rotation.
LPoint3 from_center = (from_a + from_b) * 0.5f;
LPoint3 prev_center =
LPoint3((capsule->get_point_a() + capsule->get_point_b()) * 0.5f) *
(wrt_prev_space->get_mat() * _to_2d_mat);
if (prev_center[1] > 0 || prev_center[1] > 0) {
// Nope, it did not.
return nullptr;
}
// Determine the intersection of the sphere with the polygon.
PN_stdfloat t = from_center[1] / (from_center[1] - prev_center[1]);
LPoint2 p(
prev_center[0] * t + from_center[0] * (1.0f - t),
prev_center[2] * t + from_center[2] * (1.0f - t));
LPoint2 edge_p(p);
PN_stdfloat edge_dist = dist_to_polygon(p, edge_p, _points);
if (edge_dist >= 0 && edge_dist * edge_dist > from_radius_sq) {
return nullptr;
}
if (collide_cat.is_debug()) {
collide_cat.debug()
<< "intersection detected from " << entry.get_from_node_path()
<< " into " << entry.get_into_node_path() << "\n";
}
PT(CollisionEntry) new_entry = new CollisionEntry(entry);
LVector3 normal = (has_effective_normal() && capsule->get_respect_effective_normal()) ? get_effective_normal() : get_normal();
new_entry->set_surface_normal(normal);
LMatrix4 to_3d_mat;
rederive_to_3d_mat(to_3d_mat);
LPoint3 deepest = (from_a[1] < from_b[1] ? capsule->get_point_b() : capsule->get_point_a()) * wrt_mat;
PN_stdfloat from_radius = csqrt(from_radius_sq);
new_entry->set_surface_point(to_3d(edge_p, to_3d_mat));
new_entry->set_interior_point(deepest - get_normal() * from_radius);
return new_entry;
}
}