C++ TriangleList::push_back方法代码示例

bool Triangulator::check_triangle(Vertex *first, TriangleList &triangles) {
	// path is a dot
	if (first->next == first)
		return true;

	// path is a two lines
	if (first->next->next == first)
		return true;

	// path is triangle
	if (first->next->next->next == first) {
		triangles.push_back(first->index);
		triangles.push_back(first->next->index);
		triangles.push_back(first->next->next->index);
		return true;
	}

	return false;
}

  void KDTree::splitTriList( TriangleList& l, TriangleList& r, TriangleList& p, float pos )
  {
    curAxis = splitAxis;
    unsigned left, right, coplanar, side;

    //Go through every triangle in the triangle list
    for(unsigned i = 0; i < p.size(); ++i)
    {
      Triangle& tri = p[i];
      left = right = coplanar = 0;
      CountVertPositions(tri, left, right, coplanar, splitAxis, pos);

      side = max(left, max(right, coplanar));

      if(side == left)
        l.push_back(tri);
      else if(side == right)
        r.push_back(tri);
      else if(side == coplanar)
        l.push_back(tri);
    }
  }

void triangle_tree(
  const Eigen::MatrixXd & V,
  const Eigen::MatrixXi & F,
  TriTree & tree,
  TriangleList & tlist)
{
  assert(F.cols() == 3);
  tlist.clear();

  // Loop over facets
  for(int f = 0;f<F.rows();f++)
  {
    Point3 a(V(F(f,0),0), V(F(f,0),1), V(F(f,0),2));
    Point3 b(V(F(f,1),0), V(F(f,1),1), V(F(f,1),2));
    Point3 c(V(F(f,2),0), V(F(f,2),1), V(F(f,2),2));
    tlist.push_back(Triangle3( a,b,c));
  }
  // constructs AABB tree
  tree.clear();
  tree.insert(tlist.begin(),tlist.end());
}

//.........这里部分代码省略.........
        for (DWORD t = 0; t < numStripIndices - 2; ++t)
        {
            // Build the triangle that will be added to the buffer
            // CHANGED July 25, 2008:  the winding order is wrong here
            //Triangle tri = { pXIndices[t + 0], pXIndices[t + 1], pXIndices[t + 2] };
            Triangle tri = { pXIndices[t + 0], pXIndices[t + 2], pXIndices[t + 1] };



            // Convert the triangle into subset-indices by using the lookup table
            // we generated before.
            tri.index[0] = xIndicesTable.find(tri.index[0])->second;
            tri.index[1] = xIndicesTable.find(tri.index[1])->second;
            tri.index[2] = xIndicesTable.find(tri.index[2])->second;

            // Check to make sure this triangle isn't degenerate.  If it is, we can just skip
            // this triangle entirely to simplify the geometry.
            if (tri.index[0] == tri.index[1] || tri.index[1] == tri.index[2] || tri.index[0] == tri.index[2])
            {
                // Try to find the winding in the list
                std::set<size_t>::iterator currentWinding = windingChanges.find(triangles.size());

                // Add this to the winding change list, or remove the change if it's already there
                if (currentWinding != windingChanges.end())
                    windingChanges.erase(currentWinding);
                else
                    windingChanges.insert(triangles.size());

                // Don't insert a triangle here
                continue;
            }

            // Add this triangle to the list
            triangles.push_back(tri);
        }

        // Calculate the number of indices we need for the buffer
        DWORD numGeometryIndices = (DWORD)(triangles.size() * 3);

        // Allocate the destination geometry
        Geometry* pGeometry = NULL;
        if (APP_ERROR(AllocateGeometry(numVertices, numGeometryIndices, &pGeometry))("Couldn't allocate geometry"))
        {
            // Erase any geometry we made
            DeallocateGeometry(subsetGeometry);

            // Get rid of the mesh
            pSubsetIB->Unlock();
            pSubsetIB->Release();
            d3dxMesh->UnlockVertexBuffer();
            d3dxMesh->Release();

            // Free our device
            pd3dDevice->Release();

            // Error!
            return false;
        }

        // Copy the vertices needed for this subset into the buffer
        GeometryVertex* pVertices = pGeometry->pVertices;
        for (XIndicesIterator i = xIndicesTable.begin(); i != xIndicesTable.end(); ++i)
        {
            GeometryVertex* pCurrentVertex = &pVertices[i->second];
            *pCurrentVertex = pXVertices[i->first];

void Renderer::Render( void )
{
	for (unsigned i = 0; i < m_renderUnitList.size(); i++)
	{
		RenderUnit* renderUnit = m_renderUnitList[i];

		unsigned nVerts = renderUnit->m_vb->Size();
		unsigned nTriangles = renderUnit->m_ib->Size() / 3;

		VsOutList vsOuts(nVerts);
		TriangleList triangles;

		// 对每个顶点执行VS
		for (unsigned j = 0; j < nVerts; j++)
		{
			vsOuts[j] = renderUnit->m_vs->Main((*renderUnit->m_vb)[j]);
		}

		// triangle setup (trivial-rejection, clipping)
		for (unsigned j = 0; j < nTriangles; j++)
		{
			Triangle tri;
			tri.iV0 = (*renderUnit->m_ib)[3 * j + 0];
			tri.iV1 = (*renderUnit->m_ib)[3 * j + 1];
			tri.iV2 = (*renderUnit->m_ib)[3 * j + 2];

			if (TrivialReject(tri, vsOuts))
			{
				continue;
			}
			else if (RemoveBackface(tri, vsOuts, CULL_MODE_CCW))
			{
				continue;
			}
			else if (TrivialAccept(tri, vsOuts))
			{
				triangles.push_back(tri);
			}
			else
			{
				// TODO: do clipping here
				triangles.push_back(tri);
			}
		}

		int halfRtWidth = m_renderTarget->GetWidth() >> 1;
		int halfRtHeight = m_renderTarget->GetHeight() >> 1;

		for (unsigned j = 0; j < vsOuts.size(); j++)
		{
			Vector4& position = vsOuts[j].position;

			// perspective-divide
			position.x /= position.w; 
			position.y /= position.w;
			position.z /= position.w;

			// 转化到屏幕坐标
			position.x = ( position.x + 1.0f) * halfRtWidth;
			position.y = (-position.y + 1.0f) * halfRtHeight;
		}
		
		// 光栅化每个三角形
		for (unsigned j = 0; j < triangles.size(); j++)
		{
			VertexShaderOutput& v0 = vsOuts[triangles[j].iV0];
			VertexShaderOutput& v1 = vsOuts[triangles[j].iV1];
			VertexShaderOutput& v2 = vsOuts[triangles[j].iV2];

			if (renderUnit->m_wireFrame)	// fill mode: wireframe
			{
				int x0 = int(v0.position.x);
				int y0 = int(v0.position.y);
				int x1 = int(v1.position.x);
				int y1 = int(v1.position.y);
				int x2 = int(v2.position.x);
				int y2 = int(v2.position.y);

				DrawLine(x0, y0, x1, y1, 0xFFFFFFFF);
				DrawLine(x0, y0, x2, y2, 0xFFFFFFFF);
				DrawLine(x1, y1, x2, y2, 0xFFFFFFFF);
			}
			else	// fill mode: solid
			{
				VertexShaderOutput* sv;
				VertexShaderOutput* mv;
				VertexShaderOutput* ev;
				
				// 按Y值给三个顶点排序
				if (v0.position.y < v1.position.y)
				{
					sv = &v0;
					ev = &v1;
				}
				else
				{
					sv = &v1;
					ev = &v0;
				}

//.........这里部分代码省略.........