/// <summary>
/// 切割模型
/// </summary>
/// <param name="includeSection"></param>
/// <param name="includeOppositeFace"></param>
/// <param name="remainOrigin">是否保留原始模型</param>
/// <returns></returns>
public SlicedMesh Slice(bool includeSection, bool includeOppositeFace)
{
this.m_includeSection = includeSection;
this.m_includeOppositeFace = includeOppositeFace;
Mesh sliceMesh = this.m_originMesh;
GeometryUtility.TriangleWindingOrder meshWindingOrder = GeometryUtility.GetMeshWindingOrder(sliceMesh);
SlicedMesh slicedMesh = new SlicedMesh(meshWindingOrder);
for (int j = 0; j < sliceMesh.triangles.Length; j += 3)
{
int vertexIndex0 = sliceMesh.triangles[j];
int vertexIndex1 = sliceMesh.triangles[j + 1];
int vertexIndex2 = sliceMesh.triangles[j + 2];
Vector3 vertexPosition0 = sliceMesh.vertices[vertexIndex0];
Vector3 vertexPosition1 = sliceMesh.vertices[vertexIndex1];
Vector3 vertexPosition2 = sliceMesh.vertices[vertexIndex2];
Vector2 uv0 = Vector2.zero;
Vector2 uv1 = Vector2.zero;
Vector2 uv2 = Vector2.zero;
if (sliceMesh.uv.Length != 0)
{
uv0 = sliceMesh.uv[vertexIndex0];
uv1 = sliceMesh.uv[vertexIndex1];
uv2 = sliceMesh.uv[vertexIndex2];
}
GeometryUtility.Triangle triangle = new GeometryUtility.Triangle(vertexPosition0, vertexPosition1, vertexPosition2, uv0, uv1, uv2);
GeometryUtility.PlaneTriangleIntersectionResult intersectionResult = GeometryUtility.GetPlaneTriangleIntersectionResult(this.m_slicerPlane, triangle, includeOppositeFace);
slicedMesh.UpperMeshTriangleList.AddRange(intersectionResult.UpperTriangleList);
slicedMesh.UnderMeshTriangleList.AddRange(intersectionResult.UnderTriangleList);
slicedMesh.CrossMeshVertexList.AddRange(intersectionResult.IntersectionPointList);
}
this.m_slicedUpperMesh = slicedMesh.UpperMesh;
if (includeOppositeFace)
{
this.m_slicedUnderMesh = slicedMesh.UnderMesh;
}
//交界处的mesh
if (includeSection)
{
//上交界处的法线是切面的反方向
this.m_slicedUpperCrossMesh = slicedMesh.GetUpperCrossMesh(m_slicerPlane.normal);
if (includeOppositeFace)
{
this.m_slicedUnderCrossMesh = slicedMesh.GetUnderCrossMesh(m_slicerPlane.normal);
}
}
return(slicedMesh);
}
/// <summary>
/// 提供方便方法直接切割TriangleList
/// </summary>
/// <param name="triangleList"></param>
/// <param name="includeSection"></param>
/// <param name="includeOppositeFace"></param>
/// <returns></returns>
public static SlicedMesh SliceTriangleList(List <GeometryUtility.Triangle> triangleList, Plane slicerPlane, bool includeSection, bool includeOppositeFace)
{
if (triangleList.Count < 1)
{
return(null);
}
GeometryUtility.TriangleWindingOrder windingOrder = triangleList[0].WindingOrder;
SlicedMesh slicedMesh = new SlicedMesh(windingOrder);
for (int i = 0; i < triangleList.Count; ++i)
{
GeometryUtility.Triangle sliceTriangle = triangleList[i];
GeometryUtility.PlaneTriangleIntersectionResult planeTriangleIntersectionResult = GeometryUtility.GetPlaneTriangleIntersectionResult(slicerPlane, sliceTriangle, includeOppositeFace);
if (!planeTriangleIntersectionResult.IsIntersection)
{
continue;
}
slicedMesh.UpperMeshTriangleList.AddRange(planeTriangleIntersectionResult.UpperTriangleList);
if (includeSection)
{
slicedMesh.CrossMeshVertexList.AddRange(planeTriangleIntersectionResult.IntersectionPointList);
}
}
return(slicedMesh);
}