public void TrySplit(int min_size, float threshold, int grid_size, List <VertexPositionColorNormal> vertices)
{
// This part taken from http://www.volume-gfx.com/ as a listed optimization, though it's disabled right now by setting the value to 1000
float minSplitDistanceDiagonalFactor = 1000.0f;
if (Sampler.Sample(position + Vector2.One * size * 0.5f) > size * (float)Math.Sqrt(2) * minSplitDistanceDiagonalFactor || size <= min_size || GetError(threshold) < threshold)
{
dualgrid_pos = 0.5f * size * Vector2.One;
isovalue = Sampler.Sample(dualgrid_pos);
normal = Sampler.GetNormal(dualgrid_pos);
vertex_index = vertices.Count;
leaf = true;
Color n_c = new Color(210, 220, 210);
vertices.Add(new VertexPositionColorNormal(new Vector3(position * grid_size + dualgrid_pos * grid_size, 0), n_c, new Vector3(normal, 0)));
return;
}
for (int i = 0; i < 4; i++)
{
children[i] = new QuadtreeNode();
children[i].index = i;
children[i].position = position + (float)(size / 2) * new Vector2(i / 2, i % 2);
children[i].size = size / 2;
children[i].TrySplit(min_size, threshold, grid_size, vertices);
}
}
public QuadtreeNode()
{
//type = QuadtreeNodeType.None;
position = Vector2.Zero;
size = 0;
children = new QuadtreeNode[4];
vertex_index = -1;
//draw_info = new QuadtreeDrawInfo();
}
public void ConstructTreeGrid(QuadtreeNode node)
{
if (node == null)
{
return;
}
VertexPositionColor[] vs = new VertexPositionColor[16];
int x = (int)node.position.X * this.Size;
int y = (int)node.position.Y * this.Size;
Color c = Color.LightSteelBlue;
Color v = Color.LightSalmon;
float size = node.size * this.Size;
vs[0] = new VertexPositionColor(new Vector3(x + 0 * size, y + 0 * size, 0), c);
vs[1] = new VertexPositionColor(new Vector3(x + 1 * size, y + 0 * size, 0), c);
vs[2] = new VertexPositionColor(new Vector3(x + 1 * size, y + 0 * size, 0), c);
vs[3] = new VertexPositionColor(new Vector3(x + 1 * size, y + 1 * size, 0), c);
vs[4] = new VertexPositionColor(new Vector3(x + 1 * size, y + 1 * size, 0), c);
vs[5] = new VertexPositionColor(new Vector3(x + 0 * size, y + 1 * size, 0), c);
vs[6] = new VertexPositionColor(new Vector3(x + 0 * size, y + 1 * size, 0), c);
vs[7] = new VertexPositionColor(new Vector3(x + 0 * size, y + 0 * size, 0), c);
OutlineBuffer.SetData <VertexPositionColor>(OutlineLocation * VertexPositionColor.VertexDeclaration.VertexStride, vs, 0, 8, VertexPositionColor.VertexDeclaration.VertexStride);
OutlineLocation += 8;
if (node.leaf && false)
{
x += (int)(node.dualgrid_pos.X * (float)this.Size);
y += (int)(node.dualgrid_pos.Y * (float)this.Size);
float r = 2;
vs[8] = new VertexPositionColor(new Vector3(x - r, y - r, 0), v);
vs[9] = new VertexPositionColor(new Vector3(x + r, y - r, 0), v);
vs[10] = new VertexPositionColor(new Vector3(x + r, y - r, 0), v);
vs[11] = new VertexPositionColor(new Vector3(x + r, y + r, 0), v);
vs[12] = new VertexPositionColor(new Vector3(x + r, y + r, 0), v);
vs[13] = new VertexPositionColor(new Vector3(x - r, y + r, 0), v);
vs[14] = new VertexPositionColor(new Vector3(x - r, y + r, 0), v);
vs[15] = new VertexPositionColor(new Vector3(x - r, y - r, 0), v);
OutlineBuffer.SetData <VertexPositionColor>(OutlineLocation * VertexPositionColor.VertexDeclaration.VertexStride, vs, 0, 16, VertexPositionColor.VertexDeclaration.VertexStride);
OutlineLocation += 16;
}
for (int i = 0; i < 4; i++)
{
ConstructTreeGrid(node.children[i]);
}
}
public static void ProcessEdge(QuadtreeNode q1, QuadtreeNode q2, int edge, List<int> indices, List<Cell> cells)
{
if (q1.leaf && q2.leaf)
return;
for (int i = 0; i < 2; i++)
{
QuadtreeNode n1 = (q1.leaf ? q1 : q1.children[edge_children[edge, i, 0]]);
QuadtreeNode n2 = (q2.leaf ? q2 : q2.children[edge_children[edge, i, 1]]);
ProcessEdge(n1, n2, edge, indices, cells);
}
if (edge == 0)
ProcessVertices((q1.leaf ? q1 : q1.children[vertex_children[edge, 0, 0]]), (q1.leaf ? q1 : q1.children[vertex_children[edge, 0, 1]]), (q2.leaf ? q2 : q2.children[vertex_children[edge, 1, 0]]), (q2.leaf ? q2 : q2.children[vertex_children[edge, 1, 1]]), indices, cells);
else
ProcessVertices((q1.leaf ? q1 : q1.children[vertex_children[edge, 0, 0]]), (q2.leaf ? q2 : q2.children[vertex_children[edge, 1, 0]]), (q1.leaf ? q1 : q1.children[vertex_children[edge, 0, 1]]), (q2.leaf ? q2 : q2.children[vertex_children[edge, 1, 1]]), indices, cells);
}
public static void ProcessVertices(QuadtreeNode q1, QuadtreeNode q2, QuadtreeNode q3, QuadtreeNode q4, List <int> indices, List <Cell> cells)
{
if (q1 == null || q2 == null || q3 == null || q4 == null)
{
return;
}
QuadtreeNode[] children = { q1, q2, q3, q4 };
QuadtreeNode[] leafs = new QuadtreeNode[4];
if (!children[0].leaf || !children[1].leaf || !children[2].leaf || !children[3].leaf)
{
for (int i = 0; i < 4; i++)
{
if (children[i] == null) //shouldn't happen
{
return;
}
if (children[i].leaf)
{
leafs[i] = children[i];
}
else
{
leafs[i] = children[i].children[middle_points[i]];
}
}
ProcessVertices(leafs[0], leafs[1], leafs[2], leafs[3], indices, cells);
}
else
{
Cell c = new Cell();
for (int i = 0; i < 4; i++)
{
indices.Add(children[connect_points[i]].vertex_index);
indices.Add(children[connect_points[(i + 1) % 4]].vertex_index);
c.Positions[i] = children[i].dualgrid_pos + children[i].position;
c.Values[i] = children[i].isovalue;
c.Normals[i] = children[i].normal;
}
cells.Add(c);
}
}
/* The following functions generate the dual grid */
public static void ProcessFace(QuadtreeNode q1, List <int> indices, List <Cell> cells)
{
if (q1 == null || q1.leaf)
{
return;
}
for (int i = 0; i < 4; i++)
{
ProcessFace(q1.children[i], indices, cells);
}
for (int i = 0; i < 4; i++)
{
QuadtreeNode c1 = q1.children[edges[i, 0]];
QuadtreeNode c2 = q1.children[edges[i, 1]];
ProcessEdge(c1, c2, i / 2, indices, cells);
}
ProcessVertices(q1.children[0], q1.children[1], q1.children[2], q1.children[3], indices, cells);
}
public static void ProcessEdge(QuadtreeNode q1, QuadtreeNode q2, int edge, List <int> indices, List <Cell> cells)
{
if (q1.leaf && q2.leaf)
{
return;
}
for (int i = 0; i < 2; i++)
{
QuadtreeNode n1 = (q1.leaf ? q1 : q1.children[edge_children[edge, i, 0]]);
QuadtreeNode n2 = (q2.leaf ? q2 : q2.children[edge_children[edge, i, 1]]);
ProcessEdge(n1, n2, edge, indices, cells);
}
if (edge == 0)
{
ProcessVertices((q1.leaf ? q1 : q1.children[vertex_children[edge, 0, 0]]), (q1.leaf ? q1 : q1.children[vertex_children[edge, 0, 1]]), (q2.leaf ? q2 : q2.children[vertex_children[edge, 1, 0]]), (q2.leaf ? q2 : q2.children[vertex_children[edge, 1, 1]]), indices, cells);
}
else
{
ProcessVertices((q1.leaf ? q1 : q1.children[vertex_children[edge, 0, 0]]), (q2.leaf ? q2 : q2.children[vertex_children[edge, 1, 0]]), (q1.leaf ? q1 : q1.children[vertex_children[edge, 0, 1]]), (q2.leaf ? q2 : q2.children[vertex_children[edge, 1, 1]]), indices, cells);
}
}
public override long Contour(float threshold)
{
Stopwatch watch = new Stopwatch();
Vertices.Clear();
Tree = new QuadtreeNode();
OutlineLocation = 0;
watch.Start();
Tree.Build(Resolution, 1, threshold, this.Size, Vertices);
DualGridCount = Vertices.Count;
if (DualGridCount > 0)
{
DualGridBuffer.SetData <VertexPositionColorNormal>(Vertices.ToArray());
}
CalculateIndexes();
watch.Stop();
ConstructTreeGrid(Tree);
return(watch.ElapsedMilliseconds);
}
public void CalculateIndexes()
{
List <int> indexes = new List <int>();
Cells.Clear();
QuadtreeNode.ProcessFace(Tree, indexes, Cells);
IndexCount = indexes.Count;
if (indexes.Count != 0)
{
IndexBuffer.SetData <int>(indexes.ToArray());
}
Vertices.Clear();
foreach (Cell c in Cells)
{
c.Polygonize(Vertices, Size);
}
VertexCount = Vertices.Count;
if (VertexCount > 0)
{
VertexBuffer.SetData <VertexPositionColorNormal>(Vertices.ToArray());
}
}
/* The following functions generate the dual grid */
public static void ProcessFace(QuadtreeNode q1, List<int> indices, List<Cell> cells)
{
if (q1 == null || q1.leaf)
return;
for (int i = 0; i < 4; i++)
{
ProcessFace(q1.children[i], indices, cells);
}
for (int i = 0; i < 4; i++)
{
QuadtreeNode c1 = q1.children[edges[i, 0]];
QuadtreeNode c2 = q1.children[edges[i, 1]];
ProcessEdge(c1, c2, i / 2, indices, cells);
}
ProcessVertices(q1.children[0], q1.children[1], q1.children[2], q1.children[3], indices, cells);
}
public void TrySplit(int min_size, float threshold, int grid_size, List<VertexPositionColorNormal> vertices)
{
// This part taken from http://www.volume-gfx.com/ as a listed optimization, though it's disabled right now by setting the value to 1000
float minSplitDistanceDiagonalFactor = 1000.0f;
if (Sampler.Sample(position + Vector2.One * size * 0.5f) > size * (float)Math.Sqrt(2) * minSplitDistanceDiagonalFactor || size <= min_size || GetError(threshold) < threshold)
{
dualgrid_pos = 0.5f * size * Vector2.One;
isovalue = Sampler.Sample(dualgrid_pos);
normal = Sampler.GetNormal(dualgrid_pos);
vertex_index = vertices.Count;
leaf = true;
Color n_c = new Color(210, 220, 210);
vertices.Add(new VertexPositionColorNormal(new Vector3(position * grid_size + dualgrid_pos * grid_size, 0), n_c, new Vector3(normal, 0)));
return;
}
for (int i = 0; i < 4; i++)
{
children[i] = new QuadtreeNode();
children[i].index = i;
children[i].position = position + (float)(size / 2) * new Vector2(i / 2, i % 2);
children[i].size = size / 2;
children[i].TrySplit(min_size, threshold, grid_size, vertices);
}
}
public static void ProcessVertices(QuadtreeNode q1, QuadtreeNode q2, QuadtreeNode q3, QuadtreeNode q4, List<int> indices, List<Cell> cells)
{
if (q1 == null || q2 == null || q3 == null || q4 == null)
return;
QuadtreeNode[] children = { q1, q2, q3, q4 };
QuadtreeNode[] leafs = new QuadtreeNode[4];
if (!children[0].leaf || !children[1].leaf || !children[2].leaf || !children[3].leaf)
{
for (int i = 0; i < 4; i++)
{
if (children[i] == null) //shouldn't happen
return;
if (children[i].leaf)
leafs[i] = children[i];
else
leafs[i] = children[i].children[middle_points[i]];
}
ProcessVertices(leafs[0], leafs[1], leafs[2], leafs[3], indices, cells);
}
else
{
Cell c = new Cell();
for (int i = 0; i < 4; i++)
{
indices.Add(children[connect_points[i]].vertex_index);
indices.Add(children[connect_points[(i + 1) % 4]].vertex_index);
c.Positions[i] = children[i].dualgrid_pos + children[i].position;
c.Values[i] = children[i].isovalue;
c.Normals[i] = children[i].normal;
}
cells.Add(c);
}
}
public void ConstructTreeGrid(QuadtreeNode node)
{
if (node == null)
return;
VertexPositionColor[] vs = new VertexPositionColor[16];
int x = (int)node.position.X * this.Size;
int y = (int)node.position.Y * this.Size;
Color c = Color.LightSteelBlue;
Color v = Color.LightSalmon;
float size = node.size * this.Size;
vs[0] = new VertexPositionColor(new Vector3(x + 0 * size, y + 0 * size, 0), c);
vs[1] = new VertexPositionColor(new Vector3(x + 1 * size, y + 0 * size, 0), c);
vs[2] = new VertexPositionColor(new Vector3(x + 1 * size, y + 0 * size, 0), c);
vs[3] = new VertexPositionColor(new Vector3(x + 1 * size, y + 1 * size, 0), c);
vs[4] = new VertexPositionColor(new Vector3(x + 1 * size, y + 1 * size, 0), c);
vs[5] = new VertexPositionColor(new Vector3(x + 0 * size, y + 1 * size, 0), c);
vs[6] = new VertexPositionColor(new Vector3(x + 0 * size, y + 1 * size, 0), c);
vs[7] = new VertexPositionColor(new Vector3(x + 0 * size, y + 0 * size, 0), c);
OutlineBuffer.SetData<VertexPositionColor>(OutlineLocation * VertexPositionColor.VertexDeclaration.VertexStride, vs, 0, 8, VertexPositionColor.VertexDeclaration.VertexStride);
OutlineLocation += 8;
if (node.leaf && false)
{
x += (int)(node.dualgrid_pos.X * (float)this.Size);
y += (int)(node.dualgrid_pos.Y * (float)this.Size);
float r = 2;
vs[8] = new VertexPositionColor(new Vector3(x - r, y - r, 0), v);
vs[9] = new VertexPositionColor(new Vector3(x + r, y - r, 0), v);
vs[10] = new VertexPositionColor(new Vector3(x + r, y - r, 0), v);
vs[11] = new VertexPositionColor(new Vector3(x + r, y + r, 0), v);
vs[12] = new VertexPositionColor(new Vector3(x + r, y + r, 0), v);
vs[13] = new VertexPositionColor(new Vector3(x - r, y + r, 0), v);
vs[14] = new VertexPositionColor(new Vector3(x - r, y + r, 0), v);
vs[15] = new VertexPositionColor(new Vector3(x - r, y - r, 0), v);
OutlineBuffer.SetData<VertexPositionColor>(OutlineLocation * VertexPositionColor.VertexDeclaration.VertexStride, vs, 0, 16, VertexPositionColor.VertexDeclaration.VertexStride);
OutlineLocation += 16;
}
for (int i = 0; i < 4; i++)
{
ConstructTreeGrid(node.children[i]);
}
}
public override long Contour(float threshold)
{
Stopwatch watch = new Stopwatch();
Vertices.Clear();
Tree = new QuadtreeNode();
OutlineLocation = 0;
watch.Start();
Tree.Build(Resolution, 1, threshold, this.Size, Vertices);
DualGridCount = Vertices.Count;
if (DualGridCount > 0)
DualGridBuffer.SetData<VertexPositionColorNormal>(Vertices.ToArray());
CalculateIndexes();
watch.Stop();
ConstructTreeGrid(Tree);
return watch.ElapsedMilliseconds;
}
