internal TerrainBlock(int x_start, int y_start, int x_count, int y_count, BoundingBox box, int subdivision, Terrain owner)
{
bounds = box;
if (subdivision < owner.Subdivisions)
{
x_count /= 2;
y_count /= 2;
Vector3 new_size = box.Size / 2;
new_size.y = box.Size.y;
float offset = box.Size.x / 4;
children = new List<TerrainBlock>();
children.Add(new TerrainBlock(x_start, y_start, x_count, y_count, new BoundingBox() { Size = new_size, Position = box.Position + new Vector3(-offset, 0, offset) }, subdivision + 1, owner));
children.Add(new TerrainBlock(x_start + x_count, y_start, x_count, y_count, new BoundingBox() { Size = new_size, Position = box.Position + new Vector3(offset, 0, offset) }, subdivision + 1, owner));
children.Add(new TerrainBlock(x_start + x_count, y_start + y_count, x_count, y_count, new BoundingBox() { Size = new_size, Position = box.Position + new Vector3(offset, 0, -offset) }, subdivision + 1, owner));
children.Add(new TerrainBlock(x_start, y_start + y_count, x_count, y_count, new BoundingBox() { Size = new_size, Position = box.Position + new Vector3(-offset, 0, -offset) }, subdivision + 1, owner));
}
else
{
ib = new IndexBuffer<int>();
ib.Allocate(6 * (x_count) * (y_count));
int index = 0;
for (int i = 0; i < y_count; i++)
{
for (int j = 0; j < x_count; j++)
{
int i1 = (y_start + i) * owner.heightmap.Width + x_start + j;
int i2 = (y_start + i) * owner.heightmap.Width + x_start + j + 1;
int i3 = (y_start + i + 1) * owner.heightmap.Width + x_start + j + 1;
int i4 = (y_start + i + 1) * owner.heightmap.Width + x_start + j;
ib[index++] = i1;
ib[index++] = i3;
ib[index++] = i2;
ib[index++] = i1;
ib[index++] = i4;
ib[index++] = i3;
}
}
ib.BufferData(VboUsage.GL_STATIC_DRAW);
ib.FreeClientData();
}
}
internal TerrainBlock(Terrain owner, List<int> indices, BoundingBox box, int subdivision)
{
bounds = box;
if (subdivision < owner.Subdivisions)
{
Vector3 new_size = box.Size / 2;
new_size.y = box.Size.y;
float offset = box.Size.x / 4;
children = new List<TerrainBlock>();
children.Add(new TerrainBlock(owner, indices, new BoundingBox() { Size = new_size, Position = box.Position + new Vector3(-offset, 0, offset) }, subdivision + 1));
children.Add(new TerrainBlock(owner, indices, new BoundingBox() { Size = new_size, Position = box.Position + new Vector3(offset, 0, offset) }, subdivision + 1));
children.Add(new TerrainBlock(owner, indices, new BoundingBox() { Size = new_size, Position = box.Position + new Vector3(offset, 0, -offset) }, subdivision + 1));
children.Add(new TerrainBlock(owner, indices, new BoundingBox() { Size = new_size, Position = box.Position + new Vector3(-offset, 0, -offset) }, subdivision + 1));
}
else
{
List<int> mil = new List<int>();
for (int i = 0; i < indices.Count; i += 3)
{
var i1 = indices[i];
var i2 = indices[i + 1];
var i3 = indices[i + 2];
var v1 = owner.vb[i1];
var v2 = owner.vb[i2];
var v3 = owner.vb[i3];
var p1 = new Vector2(box.Position.x - box.Size.x / 2, box.Position.z - box.Size.z / 2);
var p2 = new Vector2(box.Position.x + box.Size.x / 2, box.Position.z + box.Size.z / 2);
if ((v1.Position.x >= p1.x && v1.Position.x <= p2.x && v1.Position.z >= p1.y && v1.Position.z <= p2.y) ||
(v2.Position.x >= p1.x && v2.Position.x <= p2.x && v2.Position.z >= p1.y && v2.Position.z <= p2.y) ||
(v3.Position.x >= p1.x && v3.Position.x <= p2.x && v3.Position.z >= p1.y && v3.Position.z <= p2.y))
{
mil.Add(i1);
mil.Add(i2);
mil.Add(i3);
}
}
ib = new IndexBuffer<int>();
ib.Allocate(mil);
ib.BufferData(VboUsage.GL_STATIC_DRAW);
//mil.Clear();
}
}