fix raycast

This commit is contained in:
Irlan 2017-04-11 11:58:33 -03:00
parent 005d2bc117
commit d082c59754
2 changed files with 32 additions and 28 deletions

View File

@ -35,13 +35,13 @@ public:
void ComputeAABB(b3AABB3* output, const b3Transform& xf) const;
void ComputeAABB(b3AABB3* output, const b3Transform& xf, u32 index) const;
void ComputeAABB(b3AABB3* output, const b3Transform& xf, u32 childIndex) const;
bool TestPoint(const b3Vec3& point, const b3Transform& xf) const;
bool RayCast(b3RayCastOutput* output, const b3RayCastInput& input, const b3Transform& xf) const;
bool RayCast(b3RayCastOutput* output, const b3RayCastInput& input, const b3Transform& xf, u32 index) const;
bool RayCast(b3RayCastOutput* output, const b3RayCastInput& input, const b3Transform& xf, u32 childIndex) const;
const b3Mesh* m_mesh;
};

View File

@ -76,19 +76,18 @@ bool b3MeshShape::RayCast(b3RayCastOutput* output, const b3RayCastInput& input,
{
B3_ASSERT(index < m_mesh->triangleCount);
b3Triangle* triangle = m_mesh->triangles + index;
b3Vec3 p1 = input.p1;
b3Vec3 p2 = input.p2;
b3Vec3 d = p2 - p1;
b3Vec3 v1 = m_mesh->vertices[triangle->v1];
b3Vec3 v2 = m_mesh->vertices[triangle->v2];
b3Vec3 v3 = m_mesh->vertices[triangle->v3];
// Put the ray into the mesh's frame of reference.
b3Vec3 p1 = b3MulT(xf, input.p1);
b3Vec3 p2 = b3MulT(xf, input.p2);
b3Vec3 d = p2 - p1;
b3Vec3 n = b3Cross(v2 - v1, v3 - v1);
n.Normalize();
float32 offset = b3Dot(n, v1);
float32 numerator = b3Dot(n, v1 - p1);
float32 denominator = b3Dot(n, d);
@ -98,6 +97,8 @@ bool b3MeshShape::RayCast(b3RayCastOutput* output, const b3RayCastInput& input,
}
float32 t = numerator / denominator;
// Is the intersection point on the segment?
if (t < 0.0f || input.maxFraction < t)
{
return false;
@ -108,17 +109,21 @@ bool b3MeshShape::RayCast(b3RayCastOutput* output, const b3RayCastInput& input,
float32 w[4];
b3BarycentricCoordinates(w, v1, v2, v3, q);
// Is the intersection point on the triangle?
if (w[0] > 0.0f && w[1] > 0.0f && w[2] > 0.0f)
{
output->fraction = t;
// Does the ray start from below or above the triangle?
if (numerator > 0.0f)
{
output->normal = -n;
output->normal = -b3Mul(xf.rotation, n);
}
else
{
output->normal = n;
output->normal = b3Mul(xf.rotation, n);
}
return true;
}
@ -129,42 +134,41 @@ struct b3MeshRayCastCallback
{
float32 Report(const b3RayCastInput& input, u32 proxyId)
{
u32 index = mesh->m_mesh->tree.GetUserData(proxyId);
b3RayCastOutput indexOutput;
if (mesh->RayCast(&indexOutput, input, xf, index))
u32 childIndex = mesh->m_mesh->tree.GetUserData(proxyId);
b3RayCastOutput childOutput;
if (mesh->RayCast(&childOutput, input, xf, childIndex))
{
hit = true;
if (indexOutput.fraction < output.fraction)
// Track minimum time of impact to require less memory.
if (childOutput.fraction < output.fraction)
{
output = indexOutput;
hit = true;
output = childOutput;
}
}
return 1.0f;
}
b3Transform xf;
const b3MeshShape* mesh;
b3Transform xf;
bool hit;
b3RayCastOutput output;
};
bool b3MeshShape::RayCast(b3RayCastOutput* output, const b3RayCastInput& input, const b3Transform& xf) const
{
// Put the ray into the mesh's frame of reference.
b3RayCastInput subInput;
subInput.p1 = b3MulT(xf.rotation, input.p1 - xf.position);
subInput.p2 = b3MulT(xf.rotation, input.p2 - xf.position);
subInput.maxFraction = input.maxFraction;
b3MeshRayCastCallback callback;
callback.mesh = this;
callback.xf = xf;
callback.hit = false;
callback.output.fraction = B3_MAX_FLOAT;
m_mesh->tree.RayCast(&callback, subInput);
m_mesh->tree.RayCast(&callback, input);
output->fraction = callback.output.fraction;
output->normal = b3Mul(xf.rotation, callback.output.normal);
output->normal = callback.output.normal;
return callback.hit;
}
}