godot-module-template/engine/thirdparty/jolt_physics/Jolt/Physics/Collision/CollideShapeVsShapePerLeaf.h
2025-04-12 18:40:44 +02:00

94 lines
4.9 KiB
C++

// Jolt Physics Library (https://github.com/jrouwe/JoltPhysics)
// SPDX-FileCopyrightText: 2025 Jorrit Rouwe
// SPDX-License-Identifier: MIT
#pragma once
#include <Jolt/Physics/Collision/CollideShape.h>
#include <Jolt/Physics/Collision/CollisionDispatch.h>
#include <Jolt/Core/STLLocalAllocator.h>
JPH_NAMESPACE_BEGIN
/// Collide 2 shapes and returns at most 1 hit per leaf shape pairs that overlapping. This can be used when not all contacts between the shapes are needed.
/// E.g. when testing a compound with 2 MeshShapes A and B against a compound with 2 SphereShapes C and D, then at most you'll get 4 collisions: AC, AD, BC, BD.
/// The default CollisionDispatch::sCollideShapeVsShape function would return all intersecting triangles in A against C, all in B against C etc.
/// @param inShape1 The first shape
/// @param inShape2 The second shape
/// @param inScale1 Local space scale of shape 1 (scales relative to its center of mass)
/// @param inScale2 Local space scale of shape 2 (scales relative to its center of mass)
/// @param inCenterOfMassTransform1 Transform to transform center of mass of shape 1 into world space
/// @param inCenterOfMassTransform2 Transform to transform center of mass of shape 2 into world space
/// @param inSubShapeIDCreator1 Class that tracks the current sub shape ID for shape 1
/// @param inSubShapeIDCreator2 Class that tracks the current sub shape ID for shape 2
/// @param inCollideShapeSettings Options for the CollideShape test
/// @param ioCollector The collector that receives the results.
/// @param inShapeFilter allows selectively disabling collisions between pairs of (sub) shapes.
/// @tparam LeafCollector The type of the collector that will be used to collect hits between leaf pairs. Must be either AnyHitCollisionCollector<CollideShapeCollector> to get any hit (cheapest) or ClosestHitCollisionCollector<CollideShapeCollector> to get the deepest hit (more expensive).
template <class LeafCollector>
void CollideShapeVsShapePerLeaf(const Shape *inShape1, const Shape *inShape2, Vec3Arg inScale1, Vec3Arg inScale2, Mat44Arg inCenterOfMassTransform1, Mat44Arg inCenterOfMassTransform2, const SubShapeIDCreator &inSubShapeIDCreator1, const SubShapeIDCreator &inSubShapeIDCreator2, const CollideShapeSettings &inCollideShapeSettings, CollideShapeCollector &ioCollector, const ShapeFilter &inShapeFilter = { })
{
// Tracks information we need about a leaf shape
struct LeafShape
{
LeafShape() = default;
LeafShape(const AABox &inBounds, Mat44Arg inCenterOfMassTransform, Vec3Arg inScale, const Shape *inShape, const SubShapeIDCreator &inSubShapeIDCreator) :
mBounds(inBounds),
mCenterOfMassTransform(inCenterOfMassTransform),
mScale(inScale),
mShape(inShape),
mSubShapeIDCreator(inSubShapeIDCreator)
{
}
AABox mBounds;
Mat44 mCenterOfMassTransform;
Vec3 mScale;
const Shape * mShape;
SubShapeIDCreator mSubShapeIDCreator;
};
constexpr uint cMaxLocalLeafShapes = 32;
// A collector that stores the information we need from a leaf shape in an array that is usually on the stack but can fall back to the heap if needed
class MyCollector : public TransformedShapeCollector
{
public:
MyCollector()
{
mHits.reserve(cMaxLocalLeafShapes);
}
void AddHit(const TransformedShape &inShape) override
{
mHits.emplace_back(inShape.GetWorldSpaceBounds(), inShape.GetCenterOfMassTransform().ToMat44(), inShape.GetShapeScale(), inShape.mShape, inShape.mSubShapeIDCreator);
}
Array<LeafShape, STLLocalAllocator<LeafShape, cMaxLocalLeafShapes>> mHits;
};
// Get bounds of both shapes
AABox bounds1 = inShape1->GetWorldSpaceBounds(inCenterOfMassTransform1, inScale1);
AABox bounds2 = inShape2->GetWorldSpaceBounds(inCenterOfMassTransform2, inScale2);
// Get leaf shapes that overlap with the bounds of the other shape
MyCollector leaf_shapes1, leaf_shapes2;
inShape1->CollectTransformedShapes(bounds2, inCenterOfMassTransform1.GetTranslation(), inCenterOfMassTransform1.GetQuaternion(), inScale1, inSubShapeIDCreator1, leaf_shapes1, inShapeFilter);
inShape2->CollectTransformedShapes(bounds1, inCenterOfMassTransform2.GetTranslation(), inCenterOfMassTransform2.GetQuaternion(), inScale2, inSubShapeIDCreator2, leaf_shapes2, inShapeFilter);
// Now test each leaf shape against each other leaf
for (const LeafShape &leaf1 : leaf_shapes1.mHits)
for (const LeafShape &leaf2 : leaf_shapes2.mHits)
if (leaf1.mBounds.Overlaps(leaf2.mBounds))
{
// Use the leaf collector to collect max 1 hit for this pair and pass it on to ioCollector
LeafCollector collector;
CollisionDispatch::sCollideShapeVsShape(leaf1.mShape, leaf2.mShape, leaf1.mScale, leaf2.mScale, leaf1.mCenterOfMassTransform, leaf2.mCenterOfMassTransform, leaf1.mSubShapeIDCreator, leaf2.mSubShapeIDCreator, inCollideShapeSettings, collector, inShapeFilter);
if (collector.HadHit())
ioCollector.AddHit(collector.mHit);
}
}
JPH_NAMESPACE_END