protected GridLine GetMergeEdge(GridCube cube1,
int index1,
GridCube cube2 = null,
int index2 = 0)
{
if (cube1 != null)
{
return(cube1.Edges[index1]);
}
if (cube2 != null)
{
return(cube2.Edges[index2]);
}
return(null);
}
/// <summary>
/// Get special index of cube isolevel for marching cubes algoritm
/// </summary>
/// <param name="cube"></param>
/// <param name="isolevel"></param>
/// <returns></returns>
public int GetCubeIndex(GridCube cube, double isolevel)
{
var points = cube.Vertex;
int cubeIndex = 0;
if (points[0].CalculatedValue.HasValue && points[0].CalculatedValue.Value < isolevel)
{
cubeIndex |= 1;
}
if (points[1].CalculatedValue.HasValue && points[1].CalculatedValue.Value < isolevel)
{
cubeIndex |= 2;
}
if (points[2].CalculatedValue.HasValue && points[2].CalculatedValue.Value < isolevel)
{
cubeIndex |= 4;
}
if (points[3].CalculatedValue.HasValue && points[3].CalculatedValue.Value < isolevel)
{
cubeIndex |= 8;
}
if (points[4].CalculatedValue.HasValue && points[4].CalculatedValue.Value < isolevel)
{
cubeIndex |= 16;
}
if (points[5].CalculatedValue.HasValue && points[5].CalculatedValue.Value < isolevel)
{
cubeIndex |= 32;
}
if (points[6].CalculatedValue.HasValue && points[6].CalculatedValue.Value < isolevel)
{
cubeIndex |= 64;
}
if (points[7].CalculatedValue.HasValue && points[7].CalculatedValue.Value < isolevel)
{
cubeIndex |= 128;
}
return(cubeIndex);
}
private List <Triangle> GetTriangles(GridCube cube, double value)
{
//var edjes = cube.GetEdges();
//var index = cube.GetCubeIndex(value);
var toReturn = new List <Triangle>();
//for (int i = 0; EdgeTable.Table[index, i] != -1; i += 3)
//{
// var triangle = new GridTriangle()
// {
// Point1 = edjes[EdgeTable.Table[index, i]].CountorData.GetItem(value).Minium,
// Point2 = edjes[EdgeTable.Table[index, i + 1]].CountorData.GetItem(value).Minium,
// Point3 = edjes[EdgeTable.Table[index, i + 2]].CountorData.GetItem(value).Minium
// };
// toReturn.Add(triangle);
//if (!triangle.IsInvalid)
// {
// // var normal = VectorHelper.CalcNormal(triangle);
// // VectorHelper.AddNormals(triangle, normal);
// }
//}
return(toReturn);
}
private List <Triangle> GetTriangles(GridCube cube, double value)
{
var edjes = cube.Edges;
var index = GetCubeIndex(cube, value);
var toReturn = new List <Triangle>();
for (int i = 0; EdgesTable.Table[index, i] != -1; i += 3)
{
var vertex1 = edjes[EdgesTable.Table[index, i]];
var vertex2 = edjes[EdgesTable.Table[index, i + 1]];
var vertex3 = edjes[EdgesTable.Table[index, i + 2]];
var triangle = new Triangle(vertex1.IsoPoint, vertex2.IsoPoint, vertex3.IsoPoint);
var normalVector = triangle.GetNormal();
// All triangle points are merged togeher (Triangles share vertexes).
// This is used to show smooth model.
triangle.Point1.MergeNormal(normalVector);
triangle.Point2.MergeNormal(normalVector);
triangle.Point3.MergeNormal(normalVector);
toReturn.Add(triangle);
}
return(toReturn);
}
/// <summary>
/// Create a grid to build a model based on.
/// </summary>
/// <returns>List of the created cubes.</returns>
public List <GridCube> BuildGrid(Region3D region, double step)
{
if (step <= 0)
{
throw new ArgumentException(nameof(step) + " cannot be <=0");
}
var toReturn = new List <GridCube>();
var totalX = 0;
var totalZ = 0;
var column = 0;
var prevColumn = 0;
for (var y = region.MinY; y < region.MaxY;)
{
var isLastColumn = (y + step) > region.MaxY;
var isFirstY = column == 0;
var nextYValue = isLastColumn ? region.MaxY : y + step;
var depth = 0;
var prevDepth = 0;
var zIndex = 0;
for (var z = region.MinZ; z < region.MaxZ;)
{
var isLastDepth = (z + step) > region.MaxZ;
var isFirstZ = depth == 0;
var nextZValue = isLastDepth ? region.MaxZ : z + step;
zIndex++;
var xIndex = 0;
var prevX = region.MinX;
for (var x = region.MinX; x < region.MaxX;)
{
var isLastX = (x + step) > region.MaxX;
var isFirstX = xIndex == 0;
var nextXValue = isLastX ? region.MaxX : x + step;
if (!isLastColumn && !isLastX && !isLastDepth || (isFirstX && isLastX))
{
GridCube prevXCube = null;
if (!isFirstX)
{
prevXCube = toReturn[toReturn.Count - 1];
}
GridCube prevYCube = null;
if (!isFirstY)
{
var index = toReturn.Count - totalZ * totalX;
prevYCube = toReturn[index];
}
GridCube prevZCube = null;
if (!isFirstZ)
{
var index = toReturn.Count - totalX;
prevZCube = toReturn[index];
}
var newCube = new GridCube();
// Dont create object duplicates. Cubes edges are merged.
var edges = new List <GridLine>();
//0
var edge = GetMergeEdge(prevYCube, 4, prevZCube, 2);
edge = edge == null ? new GridLine(new Point(x, y, z) /*0*/, new Point(nextXValue, y, z) /*1*/, AxissConsts.X) : edge;
edges.Add(edge);
newCube.Vertex[0] = edge.Point1;
newCube.Vertex[1] = edge.Point2;
//1
edge = GetMergeEdge(prevYCube, 5);//, prevXCube, 3);
edge = edge ?? new GridLine(newCube.Vertex[1] /*1*/, new Point(nextXValue, y, nextZValue) /*2*/, AxissConsts.Z);
edges.Add(edge);
newCube.Vertex[2] = edge.Point2;
//2
edge = GetMergeEdge(prevYCube, 6);//, prevZCube, 0);
edge = edge ?? new GridLine(new Point(x, y, nextZValue) /*3*/, newCube.Vertex[2] /*2*/, AxissConsts.X);
edges.Add(edge);
newCube.Vertex[3] = edge.Point1;
//3
edge = GetMergeEdge(prevXCube, 1, prevYCube, 7);
edge = edge ?? new GridLine(newCube.Vertex[3] /*3*/, newCube.Vertex[0] /*0*/, AxissConsts.Z);
edges.Add(edge);
//4
edge = GetMergeEdge(prevZCube, 6);
edge = edge ?? new GridLine(new Point(x, nextYValue, z) /*4*/, new Point(nextXValue, nextYValue, z) /*5*/, AxissConsts.X);
edges.Add(edge);
newCube.Vertex[4] = edge.Point1;
newCube.Vertex[5] = edge.Point2;
//5
edge = new GridLine(newCube.Vertex[5] /*5*/, new Point(nextXValue, nextYValue, nextZValue) /*6*/, AxissConsts.Z);
edges.Add(edge);
newCube.Vertex[6] = edge.Point2;
//6
edge = new GridLine(new Point(x, nextYValue, nextZValue) /*7*/, newCube.Vertex[6] /*6*/, AxissConsts.X);
edges.Add(edge);
newCube.Vertex[7] = edge.Point1;
//7
edge = GetMergeEdge(prevXCube, 5);
edge = edge ?? new GridLine(newCube.Vertex[4] /*4*/, newCube.Vertex[7] /*7*/, AxissConsts.Y);
edges.Add(edge);
//8
edge = GetMergeEdge(prevXCube, 9, prevZCube, 11);
edge = edge == null ? new GridLine(newCube.Vertex[0] /*0*/, newCube.Vertex[4] /*4*/, AxissConsts.Y) : edge;
edges.Add(edge);
//9
edge = GetMergeEdge(prevZCube, 10);
edge = edge ?? new GridLine(newCube.Vertex[1] /*1*/, newCube.Vertex[5] /*5*/, AxissConsts.Y);
edges.Add(edge);
//10
edge = new GridLine(newCube.Vertex[2] /*2*/, newCube.Vertex[6] /*6*/, AxissConsts.Y);
edges.Add(edge);
//11
edge = GetMergeEdge(prevXCube, 10, null, 0);
edge = edge ?? new GridLine(newCube.Vertex[3] /*3*/, newCube.Vertex[7] /*7*/, AxissConsts.Y);
edges.Add(edge);
newCube.Edges = edges.ToArray();
toReturn.Add(newCube);
}
prevX = x;
xIndex++;
x = nextXValue;
}
totalX = xIndex;
prevDepth = depth;
depth++;
z = nextZValue;
}
totalZ = zIndex;
prevColumn = column;
column++;
y = nextYValue;
}
return(toReturn);
}
