void Draw_BSP_Tree(ref BSPTree tree, Vector4 eye)
{
if (tree == null)
{
return;
}
float result = tree.partition.ClassifyPoint(eye);
//float result = 1;
if (result > 0)
{
Draw_BSP_Tree(ref tree.back, eye);
Draw_Polygon_List(tree.polygons);
Draw_BSP_Tree(ref tree.front, eye);
}
else if (result < 0)
{
Draw_BSP_Tree(ref tree.front, eye);
Draw_Polygon_List(tree.polygons);
Draw_BSP_Tree(ref tree.back, eye);
}
else // result is 0
{
// the eye point is on the partition plane...
Draw_BSP_Tree(ref tree.back, eye);
Draw_BSP_Tree(ref tree.front, eye);
}
}
private void setLines()
{
Polygons = new List <Polygon3>();
VP = camera.ProjectionMatrix * camera.View;
myCanvas.Children.Clear();
//row 1
CreateCube(DummyCube, VP, new Vector4(-3, 0, 10, 0));
CreateCube(DummyCube, VP, new Vector4(0, 0, 10, 0));
CreateCube(DummyCube, VP, new Vector4(-6, 0, 10, 0));
CreateCube(DummyCube, VP, new Vector4(0, 0, 13, 0));
CreateCube(DummyCube, VP, new Vector4(-3, 0, 13, 0));
CreateCube(DummyCube, VP, new Vector4(-6, 0, 13, 0));
CreateCube(DummyCube, VP, new Vector4(-3, 0, 16, 0));
CreateCube(DummyCube, VP, new Vector4(0, 0, 16, 0));
CreateCube(DummyCube, VP, new Vector4(-6, 0, 16, 0));
//row 2
CreateCube(DummyCube, VP, new Vector4(0, -3, 10, 0));
CreateCube(DummyCube, VP, new Vector4(-3, -3, 10, 0));
CreateCube(DummyCube, VP, new Vector4(-6, -3, 10, 0));
CreateCube(DummyCube, VP, new Vector4(-3, -3, 13, 0));
CreateCube(DummyCube, VP, new Vector4(0, -3, 13, 0));
CreateCube(DummyCube, VP, new Vector4(-6, -3, 13, 0));
CreateCube(DummyCube, VP, new Vector4(-3, -3, 16, 0));
CreateCube(DummyCube, VP, new Vector4(0, -3, 16, 0));
CreateCube(DummyCube, VP, new Vector4(-6, -3, 16, 0));
//row 3
CreateCube(DummyCube, VP, new Vector4(0, 3, 10, 0));
CreateCube(DummyCube, VP, new Vector4(-3, 3, 10, 0));
CreateCube(DummyCube, VP, new Vector4(-6, 3, 10, 0));
CreateCube(DummyCube, VP, new Vector4(-3, 3, 13, 0));
CreateCube(DummyCube, VP, new Vector4(0, 3, 13, 0));
CreateCube(DummyCube, VP, new Vector4(-6, 3, 13, 0));
CreateCube(DummyCube, VP, new Vector4(-3, 3, 16, 0));
CreateCube(DummyCube, VP, new Vector4(0, 3, 16, 0));
CreateCube(DummyCube, VP, new Vector4(-6, 3, 16, 0));
//DrawLineFromLocal(DummyLine, new Vector4(-2, 0, 40, 0), VP);
//DrawLineFromLocal(DummyLine, new Vector4(4, 0, 40, 0), VP);
BSPTree tree = new BSPTree();
tree.BuildBSPTree(ref tree, Polygons);
Draw_BSP_Tree(ref tree, new Vector4(camera.Position, 0));
}
public void BuildBSPTree(ref BSPTree tree, List <Polygon3> polygons)
{
Polygon3 root = polygons.First();
polygons.RemoveAt(0);
tree.partition = new Plane(root.Points[0], root.Points[1], root.Points[2]);
tree.polygons.Add(root);
List <Polygon3> frontlist = new List <Polygon3>();
List <Polygon3> backlist = new List <Polygon3>();
while (polygons.Count > 0)
{
var poly = polygons.First();
polygons.RemoveAt(0);
var result = tree.partition.ClassifyPolygon(poly);
switch (result)
{
case Result.COINCIDENT:
tree.polygons.Add(poly);
break;
case Result.IN_BACK_OF:
backlist.Add(poly);
break;
case Result.IN_FRONT_OF:
frontlist.Add(poly);
break;
case Result.SPANNING:
Polygon3 front_piece = new Polygon3(), back_piece = new Polygon3();
Split_Polygon(poly, tree.partition, ref front_piece, ref back_piece);
backlist.Add(back_piece);
frontlist.Add(front_piece);
break;
}
}
if (!(frontlist.Count() == 0))
{
tree.front = new BSPTree();
BuildBSPTree(ref tree.front, frontlist);
}
if (!(backlist.Count() == 0))
{
tree.back = new BSPTree();
BuildBSPTree(ref tree.back, backlist);
}
}
public WorldData(string filePath)
{
using (StreamReader sr = new StreamReader(filePath))
{
int id = 0;
string line;
var vertices = new List <Vector4>();
while ((line = sr.ReadLine()) != null)
{
if (line.Length > 0)
{
string[] points = line.Split(' ');
switch (line[0])
{
case 'v':
vertices.Add(new Vector4(float.Parse(points[1]), float.Parse(points[2]), float.Parse(points[3]), 1.0F));
break;
case 'f':
var poly = new Polygon {
ID = id++, vertices = new Vector4[points.Length - 1]
};
for (int i = 0; i < points.Length - 1; i++)
{
poly.vertices[i] = vertices[int.Parse(points[i + 1]) - 1];
}
poly.normal = Transformations.CalculateSurfaceNormal(poly);
Polygons.Add(poly);
break;
}
}
}
}
BSPTree = new BSPTree(Polygons);
Polygons = BSPTree.Polygons;
}
private void Split_Polygon(Polygon3 poly, Plane part, ref Polygon3 front, ref Polygon3 back)
{
int count = poly.NumVertices(),
out_c = 0, in_c = 0;
Vector4 ptA, ptB;
double sideA, sideB;
Vector4[] outpts = new Vector4[MAXPTS],
inpts = new Vector4[MAXPTS];
List <Vector4> outptsl = new List <Vector4>(),
inptsl = new List <Vector4>();
ptA = poly.Points.Last();
sideA = part.ClassifyPoint(ptA);
for (short i = -1; ++i < count;)
{
ptB = poly.Points.ElementAt(i);
sideB = part.ClassifyPoint(ptB);
if (sideB > 0)
{
if (sideA < 0)
{
// compute the intersection point of the line
// from point A to point B with the partition
// plane. This is a simple ray-plane intersection.
Vector4 v = ptB - ptA;
float sect = -part.ClassifyPoint(ptA) / Vector4.Distance(part.Normal, v);
outptsl.Add(ptA + (v * sect));
inptsl.Add(ptA + (v * sect));
in_c++;
out_c++;
}
//outpts[out_c++] = ptB;
outptsl.Add(ptB);
out_c++;
}
else if (sideB < 0)
{
if (sideA > 0)
{
// compute the intersection point of the line
// from point A to point B with the partition
// plane. This is a simple ray-plane intersection.
Vector4 v = ptB - ptA;
float sect = -part.ClassifyPoint(ptA) / Vector4.Distance(part.Normal, v);
//outpts[out_c++] = inpts[in_c++] = ptA + (v * sect);
outptsl.Add(ptA + (v * sect));
inptsl.Add(ptA + (v * sect));
in_c++;
out_c++;
}
inptsl.Add(ptB);
in_c++;
}
else
{
// outpts[out_c++] = inpts[in_c++] = v;
outptsl.Add(ptB);
inptsl.Add(ptB);
in_c++;
out_c++;
}
ptA = ptB;
sideA = sideB;
}
front = new Polygon3();
front.Points = outptsl.ToList();
back = new Polygon3();
back.Points = inptsl.ToList();
}