/**
 * PANDA 3D SOFTWARE
 * Copyright (c) Carnegie Mellon University.  All rights reserved.
 *
 * All use of this software is subject to the terms of the revised BSD
 * license.  You should have received a copy of this license along
 * with this source code in a file named "LICENSE."
 *
 * @file physxClothMeshDesc.cxx
 * @author enn0x
 * @date 2010-03-28
 */

#include "physxClothMeshDesc.h"
#include "physxManager.h"

#include "nodePathCollection.h"
#include "geomNode.h"
#include "geomVertexReader.h"

/**
 * Sets the number of vertices to be stored within this triangle mesh.  The
 * function allocates memory for the vertices, but it does not set any
 * vertices.
 *
 * This method must be called before any calls to set_vertex are done!
 */
void PhysxClothMeshDesc::
set_num_vertices(unsigned int numVertices) {

  // Vertices
  if (_desc.points) {
    delete [] _points;
  }

  _points = new NxVec3[numVertices];

  _desc.numVertices = numVertices;
  _desc.points = _points;

  // Texture coordinates
  if (_texcoords) {
    delete [] _texcoords;
  }

  _texcoords = new LPoint2f[numVertices];
}

/**
 * Sets a single vertex.  You have to call the function set_num_vertices
 * before you can call this function.
 */
void PhysxClothMeshDesc::
set_vertex(unsigned int idx, const LPoint3f &vert, const LPoint2f &texcoord) {

  nassertv(_desc.numVertices > idx);

  _points[idx] = PhysxManager::point3_to_nxVec3(vert);
  _texcoords[idx] = texcoord;
}

/**
 * Sets the number of triangles to be stored in this triangle mesh.
 *
 * This method must be called before any calls to set_triangle are done!
 */
void PhysxClothMeshDesc::
set_num_triangles(unsigned int numTriangles) {

  if (_desc.triangles) {
    delete [] _triangles;
  }

  _triangles = new NxU32[3 * numTriangles];

  _desc.numTriangles = numTriangles;
  _desc.triangles = _triangles;
}

/**
 * Sets a single triangle, by providing the three indices i1, i2, i3.
 */
void PhysxClothMeshDesc::
set_triangle(unsigned int idx,
             unsigned int i1, unsigned int i2, unsigned int i3) {

  nassertv(_desc.numTriangles > idx);

  idx = 3 * idx;
  _triangles[idx]     = i1;
  _triangles[idx + 1] = i2;
  _triangles[idx + 2] = i3;
}

/**
 * A convenience method to set the mesh data from a NodePath in a single call.
 * The method iterates over the NodePath geoms and collects data for the
 * triangle mesh.
 *
 * Do not use the following function when using this one: - set_num_vertices -
 * set_vertex - set_num_triangles - set_triangle
 */
void PhysxClothMeshDesc::
set_from_node_path(const NodePath &np) {

  pvector<LPoint3f> dataVertices;
  pvector<LPoint2f> dataTexcoords;
  pvector<int> dataIndices;

  // Collect data from NodePath
  NodePathCollection npc = np.find_all_matches( "**/+GeomNode" );
  for (int i=0; i<npc.get_num_paths(); i++) {
    NodePath gnp = npc.get_path(i);
    GeomNode *gnode = DCAST(GeomNode, gnp.node());

    for (int j=0; j<gnode->get_num_geoms(); j++) {
      CPT(Geom) geom = gnode->get_geom(j);
      CPT(GeomVertexData) vdata = geom->get_vertex_data();
      GeomVertexReader reader;

      // Vertices
      reader = GeomVertexReader(vdata, InternalName::get_vertex());
      while (!reader.is_at_end()) {
        dataVertices.push_back(reader.get_data3f());
      }

      // Texcoords
      reader = GeomVertexReader(vdata, InternalName::get_texcoord());
      while (!reader.is_at_end()) {
        dataTexcoords.push_back(reader.get_data2f());
      }

      // Indices
      for (int k=0; k<geom->get_num_primitives(); k++) {

        CPT(GeomPrimitive) prim = geom->get_primitive(k);
        prim = prim->decompose();

        for (int l=0; l<prim->get_num_primitives(); l++) {

          int s = prim->get_primitive_start(l);
          int e = prim->get_primitive_end(l);

          for (int l=s; l<e; l++) {
            dataIndices.push_back(prim->get_vertex(l));
          }
        }
      }
    }
  }

  // Set descriptor members
  int i;

  NxU32 numVertices = dataVertices.size();
  NxU32 numTriangles = dataIndices.size() / 3;

  _points = new NxVec3[numVertices];
  _triangles = new NxU32[3 * numTriangles];
  _texcoords = new LPoint2f[numVertices];

  i = 0;
  pvector<LPoint3f>::const_iterator vit;
  for (vit=dataVertices.begin(); vit!=dataVertices.end(); vit++) {
    LPoint3f v = *vit;

    _points[i] = PhysxManager::point3_to_nxVec3(v);
    i++;
  }

  i = 0;
  pvector<LPoint2f>::const_iterator tcit;
  for (tcit=dataTexcoords.begin(); tcit!=dataTexcoords.end(); tcit++) {
    LPoint2f tc = *tcit;

    _texcoords[i]   = tc;
    i++;
  }

  i = 0;
  pvector<int>::const_iterator iit;
  for(iit=dataIndices.begin(); iit!=dataIndices.end(); iit++) {
    NxU32 idx = *iit;

    _triangles[i] = idx;
    i++;
  }

  _desc.numVertices = numVertices;
  _desc.points = _points;
  _desc.numTriangles = numTriangles;
  _desc.triangles = _triangles;
}