9abcc41d52
(water) is being used. git-svn-id: svn+ssh://svn.code.sf.net/p/supertuxkart/code/main/trunk@9950 178a84e3-b1eb-0310-8ba1-8eac791a3b58
289 lines
11 KiB
C++
289 lines
11 KiB
C++
// $Id$
|
|
//
|
|
// SuperTuxKart - a fun racing game with go-kart
|
|
// Copyright (C) 2006 Joerg Henrichs
|
|
//
|
|
// This program is free software; you can redistribute it and/or
|
|
// modify it under the terms of the GNU General Public License
|
|
// as published by the Free Software Foundation; either version 3
|
|
// of the License, or (at your option) any later version.
|
|
//
|
|
// This program is distributed in the hope that it will be useful,
|
|
// but WITHOUT ANY WARRANTY; without even the implied warranty ofati
|
|
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
// GNU General Public License for more details.
|
|
//
|
|
// You should have received a copy of the GNU General Public License
|
|
// along with this program; if not, write to the Free Software
|
|
// Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
|
|
|
|
#include "physics/triangle_mesh.hpp"
|
|
|
|
#include "btBulletDynamicsCommon.h"
|
|
|
|
#include "modes/world.hpp"
|
|
|
|
// -----------------------------------------------------------------------------
|
|
/** Constructor: Initialises all data structures with zero.
|
|
*/
|
|
TriangleMesh::TriangleMesh() : m_mesh()
|
|
{
|
|
m_body = NULL;
|
|
m_motion_state = NULL;
|
|
// FIXME: on VS in release mode this statement actually overwrites
|
|
// part of the data of m_mesh, causing a crash later. Debugging
|
|
// shows that apparently m_collision_shape is at the same address
|
|
// as m_mesh->m_use32bitIndices and m_use4componentVertices
|
|
// (and m_mesh->m_weldingThreshold at m_normals
|
|
m_collision_shape = NULL;
|
|
m_collision_object = NULL;
|
|
m_user_pointer.set(this);
|
|
} // TriangleMesh
|
|
|
|
// -----------------------------------------------------------------------------
|
|
/** Destructor: delete all allocated data structures.
|
|
*/
|
|
TriangleMesh::~TriangleMesh()
|
|
{
|
|
removeAll();
|
|
} // ~TriangleMesh
|
|
|
|
// -----------------------------------------------------------------------------
|
|
/** Adds a triangle to the bullet mesh. It also stores the material used for
|
|
* this triangle, and the three normals.
|
|
* \param t1,t2,t3 Points of the triangle.
|
|
* \param n1,n2,n3 Normals at the corresponding points.
|
|
* \param m Material used for this triangle
|
|
*/
|
|
void TriangleMesh::addTriangle(const btVector3 &t1, const btVector3 &t2,
|
|
const btVector3 &t3,
|
|
const btVector3 &n1, const btVector3 &n2,
|
|
const btVector3 &n3,
|
|
const Material* m)
|
|
{
|
|
m_triangleIndex2Material.push_back(m);
|
|
m_normals.push_back(n1);
|
|
m_normals.push_back(n2);
|
|
m_normals.push_back(n3);
|
|
m_mesh.addTriangle(t1, t2, t3);
|
|
} // addTriangle
|
|
|
|
// -----------------------------------------------------------------------------
|
|
/** Creates a collision body only, which can be used for raycasting, but
|
|
* has no physical properties.
|
|
*/
|
|
void TriangleMesh::createCollisionShape(bool create_collision_object)
|
|
{
|
|
if(m_triangleIndex2Material.size()==0)
|
|
{
|
|
m_collision_shape = NULL;
|
|
m_motion_state = NULL;
|
|
m_body = NULL;
|
|
m_collision_object = NULL;
|
|
return;
|
|
}
|
|
// Now convert the triangle mesh into a static rigid body
|
|
m_collision_shape = new btBvhTriangleMeshShape(&m_mesh, true);
|
|
m_collision_shape->setUserPointer(&m_user_pointer);
|
|
if(create_collision_object)
|
|
{
|
|
m_collision_object = new btCollisionObject();
|
|
btTransform bt;
|
|
bt.setIdentity();
|
|
m_collision_object->setWorldTransform(bt);
|
|
}
|
|
} // createCollisionShape
|
|
|
|
// -----------------------------------------------------------------------------
|
|
/** Creates the physics body for this triangle mesh. If the body already
|
|
* exists (because it was created by a previous call to createBody)
|
|
* it is first removed from the world. This is used by loading the track
|
|
* where a physics body is used to determine the height of terrain. To have
|
|
* an optimised rigid body including all static objects, the track is then
|
|
* removed and all objects together with the track is converted again into
|
|
* a single rigid body. This avoids using irrlicht (or the graphics engine)
|
|
* for height of terrain detection).
|
|
*/
|
|
void TriangleMesh::createPhysicalBody(btCollisionObject::CollisionFlags flags)
|
|
{
|
|
// We need the collision shape, but not the collision object (since
|
|
// this will be creates when the dynamics body is anyway).
|
|
createCollisionShape(/*create_collision_object*/false);
|
|
btTransform startTransform;
|
|
startTransform.setIdentity();
|
|
m_motion_state = new btDefaultMotionState(startTransform);
|
|
btRigidBody::btRigidBodyConstructionInfo info(0.0f, m_motion_state,
|
|
m_collision_shape);
|
|
m_body=new btRigidBody(info);
|
|
World::getWorld()->getPhysics()->addBody(m_body);
|
|
|
|
m_body->setUserPointer(&m_user_pointer);
|
|
m_body->setCollisionFlags(m_body->getCollisionFlags() |
|
|
flags |
|
|
btCollisionObject::CF_CUSTOM_MATERIAL_CALLBACK);
|
|
} // createPhysicalBody
|
|
|
|
// ----------------------------------------------------------------------------
|
|
/** Removes the created body and/or collision object from the physics world.
|
|
* This is used when creating a temporary rigid body of the main track to get
|
|
* bullet raycasts. Then the main track is removed, and the track (main track
|
|
* including all additional objects which were loaded later) is converted
|
|
* again.
|
|
*/
|
|
void TriangleMesh::removeAll()
|
|
{
|
|
if(m_body)
|
|
{
|
|
World::getWorld()->getPhysics()->removeBody(m_body);
|
|
delete m_body;
|
|
delete m_motion_state;
|
|
m_body = NULL;
|
|
m_motion_state = NULL;
|
|
}
|
|
if(m_collision_object)
|
|
{
|
|
delete m_collision_object;
|
|
m_collision_object = NULL;
|
|
}
|
|
delete m_collision_shape;
|
|
m_collision_shape = NULL;
|
|
} // removeAll
|
|
|
|
// -----------------------------------------------------------------------------
|
|
/** Interpolates the normal at the given position for the triangle with
|
|
* a given index. The position must be inside of the given triangle.
|
|
* \param index Index of the triangle to use.
|
|
* \param position The position for which to interpolate the normal.
|
|
*/
|
|
btVector3 TriangleMesh::getInterpolatedNormal(unsigned int index,
|
|
const btVector3 &position) const
|
|
{
|
|
btVector3 p1, p2, p3;
|
|
getTriangle(index, &p1, &p2, &p3);
|
|
btVector3 n1, n2, n3;
|
|
getNormals(index, &n1, &n2, &n3);
|
|
|
|
// Compute the Barycentric coordinates of position inside triangle
|
|
// p1, p2, p3.
|
|
btVector3 edge1 = p2 - p1;
|
|
btVector3 edge2 = p3 - p1;
|
|
|
|
// Area of triangle ABC
|
|
btScalar p1p2p3 = edge1.cross(edge2).length2();
|
|
|
|
// Area of BCP
|
|
btScalar p2p3p = (p3 - p2).cross(position - p2).length2();
|
|
|
|
// Area of CAP
|
|
btScalar p3p1p = edge2.cross(position - p3).length2();
|
|
btScalar s = btSqrt(p2p3p / p1p2p3);
|
|
btScalar t = btSqrt(p3p1p / p1p2p3);
|
|
btScalar w = 1.0f - s - t;
|
|
|
|
#ifdef NORMAL_DEBUGGING
|
|
btVector3 regen_position = s * p1 + t * p2 + w * p3;
|
|
|
|
if((regen_position - position).length2() >= 0.0001f)
|
|
{
|
|
printf("bary:\n");
|
|
printf("new: %f %f %f\n", regen_position.getX(),regen_position.getY(),regen_position.getZ());
|
|
printf("old: %f %f %f\n", position.getX(), position.getY(),position.getZ());
|
|
printf("stw: %f %f %f\n", s, t, w);
|
|
printf("p1: %f %f %f\n", p1.getX(),p1.getY(),p1.getZ());
|
|
printf("p2: %f %f %f\n", p2.getX(),p2.getY(),p2.getZ());
|
|
printf("p3: %f %f %f\n", p3.getX(),p3.getY(),p3.getZ());
|
|
printf("pos: %f %f %f\n", position.getX(),position.getY(),position.getZ());
|
|
}
|
|
#endif
|
|
|
|
return s*n1 + t*n2 + w*n3;
|
|
} // getInterpolatedNormal
|
|
|
|
// ----------------------------------------------------------------------------
|
|
/** Casts a ray from 'from' to 'to'. If a triangle of this mesh was hit,
|
|
* xyz and material will be set.
|
|
* \param from/to The from and to position for the raycast/
|
|
* \param xyz The position in world where the ray hit.
|
|
* \param material The material of the mesh that was hit.
|
|
* \param normal The intrapolated normal at that position.
|
|
* \return True if a triangle was hit, false otherwise (and no output
|
|
* variable will be set.
|
|
*/
|
|
bool TriangleMesh::castRay(const btVector3 &from, const btVector3 &to,
|
|
btVector3 *xyz, const Material **material,
|
|
btVector3 *normal) const
|
|
{
|
|
if(!m_collision_shape)
|
|
{
|
|
*material=NULL;
|
|
return false;
|
|
}
|
|
|
|
btTransform trans_from;
|
|
trans_from.setIdentity();
|
|
trans_from.setOrigin(from);
|
|
|
|
btTransform trans_to;
|
|
trans_to.setIdentity();
|
|
trans_to.setOrigin(to);
|
|
|
|
btTransform world_trans;
|
|
world_trans.setIdentity();
|
|
|
|
btCollisionWorld::ClosestRayResultCallback result(from, to);
|
|
|
|
|
|
class MaterialRayResult : public btCollisionWorld::ClosestRayResultCallback
|
|
{
|
|
public:
|
|
const Material* m_material;
|
|
const TriangleMesh *m_this;
|
|
// --------------------------------------------------------------------
|
|
MaterialRayResult(const btVector3 &p1, const btVector3 &p2,
|
|
const TriangleMesh *me)
|
|
: btCollisionWorld::ClosestRayResultCallback(p1,p2)
|
|
{
|
|
m_material = NULL;
|
|
m_this = me;
|
|
} // MaterialRayResult
|
|
// --------------------------------------------------------------------
|
|
virtual btScalar addSingleResult(btCollisionWorld::LocalRayResult& rayResult,
|
|
bool normalInWorldSpace)
|
|
{
|
|
m_material =
|
|
m_this->getMaterial(rayResult.m_localShapeInfo->m_triangleIndex);
|
|
return btCollisionWorld::ClosestRayResultCallback
|
|
::addSingleResult(rayResult, normalInWorldSpace);
|
|
} // AddSingleResult
|
|
// --------------------------------------------------------------------
|
|
}; // myCollision
|
|
|
|
MaterialRayResult ray_callback(from, to, this);
|
|
|
|
// If this is a rigid body, m_collision_object is NULL, and the
|
|
// rigid body is the actual collision object.
|
|
btCollisionWorld::rayTestSingle(trans_from, trans_to,
|
|
m_collision_object ? m_collision_object
|
|
: m_body,
|
|
m_collision_shape, world_trans,
|
|
ray_callback);
|
|
if(ray_callback.hasHit())
|
|
{
|
|
*xyz = ray_callback.m_hitPointWorld;
|
|
*material = ray_callback.m_material;
|
|
if(normal)
|
|
{
|
|
*normal = ray_callback.m_hitNormalWorld;
|
|
normal->normalize();
|
|
}
|
|
}
|
|
else
|
|
{
|
|
*material = NULL;
|
|
if(normal)
|
|
normal->setValue(0, 1, 0);
|
|
}
|
|
return ray_callback.hasHit();
|
|
|
|
} // castRay
|