btTriangleIndexVertexArray::btTriangleIndexVertexArray(int numTriangles,unsigned int* triangleIndexBase,int numVertices,btScalar* vertexBase)
: m_hasAabb(0)
{
btIndexedMesh mesh;
mesh.m_numTriangles = numTriangles;
mesh.m_triangleIndexBase = triangleIndexBase;
mesh.m_numVertices = numVertices;
mesh.m_vertexBase = vertexBase;
addIndexedMesh(mesh);
}
void
PhysicsShapeMesh::addMesh(const Vector3Array& vertices, const std::vector<std::uint32_t>& face) noexcept
{
_vertexBase = vertices;
_indexBase = face;
btIndexedMesh mesh;
mesh.m_vertexType = PHY_FLOAT;
mesh.m_numVertices = _vertexBase.size();
mesh.m_vertexStride = sizeof(Vector3);
mesh.m_vertexBase = (unsigned char*)_vertexBase.data();
mesh.m_indexType = PHY_INTEGER;
mesh.m_numTriangles = _indexBase.size() / 3;
mesh.m_triangleIndexStride = sizeof(std::uint32_t) * 3;
mesh.m_triangleIndexBase = (unsigned char*)_indexBase.data();
if (_indexBase.empty())
{
auto array = new btTriangleMesh;
for (std::size_t i = 0; i < mesh.m_numVertices; i += 3)
{
btVector3 v1;
v1.setX(_vertexBase[i].x);
v1.setY(_vertexBase[i].y);
v1.setZ(_vertexBase[i].z);
btVector3 v2;
v2.setX(_vertexBase[i + 1].x);
v2.setY(_vertexBase[i + 1].y);
v2.setZ(_vertexBase[i + 1].z);
btVector3 v3;
v3.setX(_vertexBase[i + 2].x);
v3.setY(_vertexBase[i + 2].y);
v3.setZ(_vertexBase[i + 2].z);
array->addTriangle(v1, v2, v3);
}
_array = array;
}
else
{
auto array = new btTriangleIndexVertexArray;
array->addIndexedMesh(mesh);
_array = array;
}
}
btTriangleIndexVertexArray::btTriangleIndexVertexArray(int numTriangles,int* triangleIndexBase,int triangleIndexStride,int numVertices,btScalar* vertexBase,int vertexStride)
: m_hasAabb(0)
{
btIndexedMesh mesh;
mesh.m_numTriangles = numTriangles;
mesh.m_triangleIndexBase = (const unsigned char *)triangleIndexBase;
mesh.m_triangleIndexStride = triangleIndexStride;
mesh.m_numVertices = numVertices;
mesh.m_vertexBase = (const unsigned char *)vertexBase;
mesh.m_vertexStride = vertexStride;
addIndexedMesh(mesh);
}
PhysicsInterface::BodyTemplateObject Bullet::createBodyTemplateFromGeometry(const Vector<Vec3>& vertices,
const Vector<RawIndexedTriangle>& triangles,
bool deleteOnceUnused,
float customCollisionMargin)
{
if (vertices.empty() || triangles.empty())
return nullptr;
auto bodyTemplate = new BodyTemplate(deleteOnceUnused);
bodyTemplates_.append(bodyTemplate);
// Copy the geometry data
bodyTemplate->vertices = vertices;
bodyTemplate->triangles = triangles;
// Create interface to the geometry data for Bullet to use
auto mesh = btIndexedMesh();
mesh.m_numTriangles = bodyTemplate->triangles.size();
mesh.m_triangleIndexBase = reinterpret_cast<byte_t*>(bodyTemplate->triangles.getData());
mesh.m_triangleIndexStride = 3 * sizeof(unsigned int);
mesh.m_numVertices = bodyTemplate->vertices.size();
mesh.m_vertexBase = bodyTemplate->vertices.as<byte_t>();
mesh.m_vertexStride = 3 * sizeof(float);
auto meshInterface = new btTriangleIndexVertexArray();
meshInterface->addIndexedMesh(mesh);
// Calculate an AABB around the geometry
auto aabb = AABB(bodyTemplate->vertices);
// Create the collision shape
bodyTemplate->collisionShape =
new btBvhTriangleMeshShape(meshInterface, true, toBullet(aabb.getMinimum()), toBullet(aabb.getMaximum()));
if (customCollisionMargin > 0.0f)
bodyTemplate->collisionShape->setMargin(customCollisionMargin);
return bodyTemplate;
}
