OpenSimMirror/libraries/ode-0.9/OPCODE/OPC_MeshInterface.cpp

304 lines
14 KiB
C++

///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
/*
* OPCODE - Optimized Collision Detection
* Copyright (C) 2001 Pierre Terdiman
* Homepage: http://www.codercorner.com/Opcode.htm
*/
///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
/**
* Contains a mesh interface.
* \file OPC_MeshInterface.cpp
* \author Pierre Terdiman
* \date November, 27, 2002
*/
///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
/**
* This structure holds 3 vertex-pointers. It's mainly used by collision callbacks so that the app doesn't have
* to return 3 vertices to OPCODE (36 bytes) but only 3 pointers (12 bytes). It seems better but I never profiled
* the alternative.
*
* \class VertexPointers
* \author Pierre Terdiman
* \version 1.3
* \date March, 20, 2001
*/
///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
/**
* This class is an interface between us and user-defined meshes. Meshes can be defined in a lot of ways, and here we
* try to support most of them.
*
* Basically you have two options:
* - callbacks, if OPC_USE_CALLBACKS is defined in OPC_Settings.h.
* - else pointers.
*
* If using pointers, you can also use strides or not. Strides are used when OPC_USE_STRIDE is defined.
*
*
* CALLBACKS:
*
* Using callbacks is the most generic way to feed OPCODE with your meshes. Indeed, you just have to give
* access to three vertices at the end of the day. It's up to you to fetch them from your database, using
* whatever method you want. Hence your meshes can lie in system memory or AGP, be indexed or not, use 16
* or 32-bits indices, you can decompress them on-the-fly if needed, etc. On the other hand, a callback is
* called each time OPCODE needs access to a particular triangle, so there might be a slight overhead.
*
* To make things clear: geometry & topology are NOT stored in the collision system,
* in order to save some ram. So, when the system needs them to perform accurate intersection
* tests, you're requested to provide the triangle-vertices corresponding to a given face index.
*
* Ex:
*
* \code
* static void ColCallback(udword triangle_index, VertexPointers& triangle, udword user_data)
* {
* // Get back Mesh0 or Mesh1 (you also can use 2 different callbacks)
* Mesh* MyMesh = (Mesh*)user_data;
* // Get correct triangle in the app-controlled database
* const Triangle* Tri = MyMesh->GetTriangle(triangle_index);
* // Setup pointers to vertices for the collision system
* triangle.Vertex[0] = MyMesh->GetVertex(Tri->mVRef[0]);
* triangle.Vertex[1] = MyMesh->GetVertex(Tri->mVRef[1]);
* triangle.Vertex[2] = MyMesh->GetVertex(Tri->mVRef[2]);
* }
*
* // Setup callbacks
* MeshInterface0->SetCallback(ColCallback, udword(Mesh0));
* MeshInterface1->SetCallback(ColCallback, udword(Mesh1));
* \endcode
*
* Of course, you should make this callback as fast as possible. And you're also not supposed
* to modify the geometry *after* the collision trees have been built. The alternative was to
* store the geometry & topology in the collision system as well (as in RAPID) but we have found
* this approach to waste a lot of ram in many cases.
*
*
* POINTERS:
*
* If you're internally using the following canonical structures:
* - a vertex made of three 32-bits floating point values
* - a triangle made of three 32-bits integer vertex references
* ...then you may want to use pointers instead of callbacks. This is the same, except OPCODE will directly
* use provided pointers to access the topology and geometry, without using a callback. It might be faster,
* but probably not as safe. Pointers have been introduced in OPCODE 1.2.
*
* Ex:
*
* \code
* // Setup pointers
* MeshInterface0->SetPointers(Mesh0->GetFaces(), Mesh0->GetVerts());
* MeshInterface1->SetPointers(Mesh1->GetFaces(), Mesh1->GetVerts());
* \endcode
*
*
* STRIDES:
*
* If your vertices are D3D-like entities interleaving a position, a normal and/or texture coordinates
* (i.e. if your vertices are FVFs), you might want to use a vertex stride to skip extra data OPCODE
* doesn't need. Using a stride shouldn't be notably slower than not using it, but it might increase
* cache misses. Please also note that you *shouldn't* read from AGP or video-memory buffers !
*
*
* In any case, compilation flags are here to select callbacks/pointers/strides at compile time, so
* choose what's best for your application. All of this has been wrapped into this MeshInterface.
*
* \class MeshInterface
* \author Pierre Terdiman
* \version 1.3
* \date November, 27, 2002
*/
///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
// Precompiled Header
#include "Stdafx.h"
using namespace Opcode;
Point MeshInterface::VertexCache[3];
///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
/**
* Constructor.
*/
///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
MeshInterface::MeshInterface() :
#ifdef OPC_USE_CALLBACKS
mUserData (null),
mObjCallback (null),
#else
mTris (null),
mVerts (null),
#ifdef OPC_USE_STRIDE
mTriStride (sizeof(IndexedTriangle)),
mVertexStride (sizeof(Point)),
#endif
#endif
mNbTris (0),
mNbVerts (0),
Single(true)
{
}
///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
/**
* Destructor.
*/
///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
MeshInterface::~MeshInterface()
{
}
///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
/**
* Checks the mesh interface is valid, i.e. things have been setup correctly.
* \return true if valid
*/
///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
bool MeshInterface::IsValid() const
{
if(!mNbTris || !mNbVerts) return false;
#ifdef OPC_USE_CALLBACKS
if(!mObjCallback) return false;
#else
if(!mTris || !mVerts) return false;
#endif
return true;
}
///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
/**
* Checks the mesh itself is valid.
* Currently we only look for degenerate faces.
* \return number of degenerate faces
*/
///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
udword MeshInterface::CheckTopology() const
{
// Check topology. If the model contains degenerate faces, collision report can be wrong in some cases.
// e.g. it happens with the standard MAX teapot. So clean your meshes first... If you don't have a mesh cleaner
// you can try this: www.codercorner.com/Consolidation.zip
udword NbDegenerate = 0;
VertexPointers VP;
// Using callbacks, we don't have access to vertex indices. Nevertheless we still can check for
// redundant vertex pointers, which cover all possibilities (callbacks/pointers/strides).
for(udword i=0;i<mNbTris;i++)
{
GetTriangle(VP, i);
if( (VP.Vertex[0]==VP.Vertex[1])
|| (VP.Vertex[1]==VP.Vertex[2])
|| (VP.Vertex[2]==VP.Vertex[0])) NbDegenerate++;
}
return NbDegenerate;
}
#ifdef OPC_USE_CALLBACKS
///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
/**
* Callback control: setups object callback. Must provide triangle-vertices for a given triangle index.
* \param callback [in] user-defined callback
* \param user_data [in] user-defined data
* \return true if success
*/
///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
bool MeshInterface::SetCallback(RequestCallback callback, void* user_data)
{
if(!callback) return SetIceError("MeshInterface::SetCallback: callback pointer is null");
mObjCallback = callback;
mUserData = user_data;
return true;
}
#else
///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
/**
* Pointers control: setups object pointers. Must provide access to faces and vertices for a given object.
* \param tris [in] pointer to triangles
* \param verts [in] pointer to vertices
* \return true if success
*/
///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
bool MeshInterface::SetPointers(const IndexedTriangle* tris, const Point* verts)
{
if(!tris || !verts) return SetIceError("MeshInterface::SetPointers: pointer is null", null);
mTris = tris;
mVerts = verts;
return true;
}
#ifdef OPC_USE_STRIDE
///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
/**
* Strides control
* \param tri_stride [in] size of a triangle in bytes. The first sizeof(IndexedTriangle) bytes are used to get vertex indices.
* \param vertex_stride [in] size of a vertex in bytes. The first sizeof(Point) bytes are used to get vertex position.
* \return true if success
*/
///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
bool MeshInterface::SetStrides(udword tri_stride, udword vertex_stride)
{
if(tri_stride<sizeof(IndexedTriangle)) return SetIceError("MeshInterface::SetStrides: invalid triangle stride", null);
if(vertex_stride<sizeof(Point)) return SetIceError("MeshInterface::SetStrides: invalid vertex stride", null);
mTriStride = tri_stride;
mVertexStride = vertex_stride;
return true;
}
#endif
#endif
///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
/**
* Remaps client's mesh according to a permutation.
* \param nb_indices [in] number of indices in the permutation (will be checked against number of triangles)
* \param permutation [in] list of triangle indices
* \return true if success
*/
///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
bool MeshInterface::RemapClient(udword nb_indices, const udword* permutation) const
{
// Checkings
if(!nb_indices || !permutation) return false;
if(nb_indices!=mNbTris) return false;
#ifdef OPC_USE_CALLBACKS
// We can't really do that using callbacks
return false;
#else
IndexedTriangle* Tmp = new IndexedTriangle[mNbTris];
CHECKALLOC(Tmp);
#ifdef OPC_USE_STRIDE
udword Stride = mTriStride;
#else
udword Stride = sizeof(IndexedTriangle);
#endif
for(udword i=0;i<mNbTris;i++)
{
const IndexedTriangle* T = (const IndexedTriangle*)(((ubyte*)mTris) + i * Stride);
Tmp[i] = *T;
}
for(udword i=0;i<mNbTris;i++)
{
IndexedTriangle* T = (IndexedTriangle*)(((ubyte*)mTris) + i * Stride);
*T = Tmp[permutation[i]];
}
DELETEARRAY(Tmp);
#endif
return true;
}