public void SetNeighbor(QuadTreeMeshNode left, QuadTreeMeshNode right, QuadTreeMeshNode up, QuadTreeMeshNode down)
{
m_IsLeftEdge = left != null && left.isEdge && (left.m_RightBottomChild.isEdge || left.m_RightTopChild.isEdge);
m_IsRightEdge = right != null && right.isEdge && (right.m_LeftBottomChild.isEdge || right.m_LeftTopChild.isEdge);
m_IsUpEdge = up != null && up.isEdge && (up.m_RightBottomChild.isEdge || up.m_LeftBottomChild.isEdge);
m_IsDownEdge = down != null && down.isEdge && (down.m_LeftTopChild.isEdge || down.m_RightTopChild.isEdge);
if (m_IsLeftEdge || m_IsRightEdge || m_IsUpEdge || m_IsDownEdge)
{
isEdge = true;
}
//if (left != 0 || right != 0 || up != 0 || down != 0)
// combinelod += 1;
}
public QuadTreeMeshNode(QuadTreeMeshNode leftTop, QuadTreeMeshNode leftBottom,
QuadTreeMeshNode rightTop, QuadTreeMeshNode rightBottom, float offsetX, float offsetY, int cellX, int cellY,
float cellWidth, float cellHeight) : this(offsetX, offsetY, cellX, cellY, cellWidth, cellHeight)
{
if (leftTop.isEdge || leftBottom.isEdge || rightTop.isEdge || rightBottom.isEdge)
{
this.isEdge = true;
}
else
{
this.isEdge = false;
}
m_LeftBottomChild = leftBottom;
m_LeftTopChild = leftTop;
m_RightBottomChild = rightBottom;
m_RightTopChild = rightTop;
}
public Mesh GenerateMesh(Texture2D texture)
{
int cellSize = (int)Mathf.Pow(2, depth);
if (widthX <= 0 || widthZ <= 0 || samples < 1)
{
return(null);
}
QuadTreeMeshNode[,] cells = new QuadTreeMeshNode[cellSize, cellSize];
//根据贴图尺寸和单元格数量，计算分配给单个单元格的像素宽高
int w = texture.width / cellSize;
int h = texture.height / cellSize;
//计算Lod
for (int i = 0; i < cellSize; i++)
{
for (int j = 0; j < cellSize; j++)
{
var cell = new QuadTreeMeshLeaf(-widthX, -widthZ, i, j, widthX * 2 / cellSize,
widthZ * 2 / cellSize);
//为单元格分配指定区域的像素并计算极差和平均值
cell.Calculate(texture, i * w, j * h, w, h);
cells[i, j] = cell;
}
}
float dtx = widthX * 2 / cellSize;
float dty = widthZ * 2 / cellSize;
MeshVertexData cache = new MeshVertexData(cellSize, cellSize, dtx, dty, -widthX, -widthZ);
while (cellSize > 1)
{
cellSize = cellSize / 2;
QuadTreeMeshNode[,] nodes = new QuadTreeMeshNode[cellSize, cellSize];
for (int i = 0; i < cellSize; i++)
{
for (int j = 0; j < cellSize; j++)
{
QuadTreeMeshNode lb = cells[i * 2, j * 2];
QuadTreeMeshNode rb = cells[i * 2 + 1, j * 2];
QuadTreeMeshNode lt = cells[i * 2, j * 2 + 1];
QuadTreeMeshNode rt = cells[i * 2 + 1, j * 2 + 1];
QuadTreeMeshNode node = new QuadTreeMeshNode(lt, lb, rt, rb, -widthX, -widthZ, i, j, widthX * 2 / cellSize,
widthZ * 2 / cellSize);
nodes[i, j] = node;
}
}
for (int i = 0; i < cellSize; i++)
{
for (int j = 0; j < cellSize; j++)
{
var left = i != 0 ? nodes[i - 1, j] : null;
var right = i != nodes.GetLength(0) - 1 ? nodes[i + 1, j] : null;
var down = j != 0 ? nodes[i, j - 1] : null;
var up = j != nodes.GetLength(1) - 1 ? nodes[i, j + 1] : null;
nodes[i, j].SetNeighbor(left, right, up, down);
}
}
cells = nodes;
}
for (int i = 0; i < cellSize; i++)
{
for (int j = 0; j < cellSize; j++)
{
cells[i, j].UpdateMesh(cache);
}
}
return(cache.Apply(texture, uvDir, samples));
}
