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Fix wrong world AABB computation that caused broad-phase collision misses

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This commit is contained in:
Daniel Chappuis 2017-11-05 23:10:55 +01:00
parent fd427c0337
commit 6e322882eb
1 changed files with 34 additions and 16 deletions
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50
src/collision/shapes/CollisionShape.cpp
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@ -32,15 +32,19 @@
using namespace reactphysics3d;
// Constructor
CollisionShape::CollisionShape(CollisionShapeName name, CollisionShapeType type) : mName(name), mType(type), mScaling(1.0, 1.0, 1.0) {
CollisionShape::CollisionShape(CollisionShapeName name, CollisionShapeType type)
: mType(type), mName(name), mScaling(1.0, 1.0, 1.0) {
}
// Compute the world-space AABB of the collision shape given a transform
// Compute the world-space AABB of the collision shape given a transform from shape
// local-space to world-space. The technique is described in the book Real-Time Collision
// Detection by Christer Ericson.
/**
* @param[out] aabb The axis-aligned bounding box (AABB) of the collision shape
* computed in world-space coordinates
* @param transform Transform used to compute the AABB of the collision shape
* @param transform Transform from shape local-space to world-space used to compute
* the AABB of the collision shape
*/
void CollisionShape::computeAABB(AABB& aabb, const Transform& transform) const {
@ -51,20 +55,34 @@ void CollisionShape::computeAABB(AABB& aabb, const Transform& transform) const {
Vector3 maxBounds;
getLocalBounds(minBounds, maxBounds);
// Rotate the local bounds according to the orientation of the body
Matrix3x3 worldAxis = transform.getOrientation().getMatrix().getAbsoluteMatrix();
Vector3 worldMinBounds(worldAxis.getColumn(0).dot(minBounds),
worldAxis.getColumn(1).dot(minBounds),
worldAxis.getColumn(2).dot(minBounds));
Vector3 worldMaxBounds(worldAxis.getColumn(0).dot(maxBounds),
worldAxis.getColumn(1).dot(maxBounds),
worldAxis.getColumn(2).dot(maxBounds));
const Vector3 translation = transform.getPosition();
Matrix3x3 matrix = transform.getOrientation().getMatrix();
Vector3 resultMin;
Vector3 resultMax;
// Compute the minimum and maximum coordinates of the rotated extents
Vector3 minCoordinates = transform.getPosition() + worldMinBounds;
Vector3 maxCoordinates = transform.getPosition() + worldMaxBounds;
// For each of the three axis
for (int i=0; i<3; i++) {
// Add translation component
resultMin[i] = translation[i];
resultMax[i] = translation[i];
for (int j=0; j<3; j++) {
decimal e = matrix[i][j] * minBounds[j];
decimal f = matrix[i][j] * maxBounds[j];
if (e < f) {
resultMin[i] += e;
resultMax[i] += f;
}
else {
resultMin[i] += f;
resultMax[i] += e;
}
}
}
// Update the AABB with the new minimum and maximum coordinates
aabb.setMin(minCoordinates);
aabb.setMax(maxCoordinates);
aabb.setMin(resultMin);
aabb.setMax(resultMax);
}