public Mesh GenerateMesh(Texture2D texture)
{
if (cellSizeX <= 0 || cellSizeZ <= 0 || widthX <= 0 || widthZ <= 0)
{
return(null);
}
float deltaX = widthX * 2 / cellSizeX;
float deltaY = widthZ * 2 / cellSizeZ;
MeshVertexData cache = new MeshVertexData(cellSizeX, cellSizeZ, deltaX, deltaY, -widthX, -widthZ);
for (int i = 0; i < cellSizeZ; i++)
{
for (int j = 0; j < cellSizeX; j++)
{
Vector3 p0 = new Vector3(-widthX + j * deltaX, 0, -widthZ + i * deltaY);
Vector3 p1 = new Vector3(-widthX + j * deltaX, 0, -widthZ + i * deltaY + deltaY);
Vector3 p2 = new Vector3(-widthX + j * deltaX + deltaX, 0, -widthZ + i * deltaY + deltaY);
Vector3 p3 = new Vector3(-widthX + j * deltaX + deltaX, 0, -widthZ + i * deltaY);
cache.AddVertex(p0);
cache.AddVertex(p1);
cache.AddVertex(p2);
cache.AddVertex(p3);
cache.AddIndex(cache.index);
cache.AddIndex(cache.index + 1);
cache.AddIndex(cache.index + 2);
cache.AddIndex(cache.index);
cache.AddIndex(cache.index + 2);
cache.AddIndex(cache.index + 3);
cache.index += 4;
}
}
Mesh mesh = cache.Apply(texture, uvDir, samples);
return(mesh);
}
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));
}
public Mesh GenerateMesh(Texture2D texture)
{
if (cellSizeX <= 0 || cellSizeZ <= 0 || widthX <= 0 || widthZ <= 0 || maxLod < 0 || samples < 1)
{
return(null);
}
LodMeshCell[,] cells = new LodMeshCell[cellSizeX, cellSizeZ];
//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 / cellSizeX;
int h = texture.height / cellSizeZ;
//计算Lod
for (int i = 0; i < cellSizeX; i++)
{
for (int j = 0; j < cellSizeZ; j++)
{
cells[i, j] = new LodMeshCell(-widthX, -widthZ, i, j, widthX * 2 / cellSizeX,
widthZ * 2 / cellSizeZ);
//为单元格分配指定区域的像素并计算极差和平均值
cells[i, j].Calculate(texture, i * w, j * h, w, h, maxLod);
}
}
//根据上一步计算的结果，将最大lod单元格边上的格子设置lod递减
for (int i = 0; i < cellSizeX; i++)
{
for (int j = 0; j < cellSizeZ; j++)
{
LodMeshCell cell = cells[i, j];
if (cell.lod == -1)
{
continue;
}
if (cell.lod != maxLod)
{
continue;
}
for (int lx = maxLod - 1, ly = 0; lx >= 0; lx--, ly++)
{
for (int lk = 0; lk <= ly; lk++)
{
if (lk == 0 && lx == 0)
{
continue;
}
int clod = maxLod - lx - lk;
//从最大lod处往外递减lod
SetNeighborLOD(i - lx, j - lk, cellSizeX, cellSizeZ, clod, cells);
SetNeighborLOD(i + lx, j - lk, cellSizeX, cellSizeZ, clod, cells);
SetNeighborLOD(i - lx, j + lk, cellSizeX, cellSizeZ, clod, cells);
SetNeighborLOD(i + lx, j + lk, cellSizeX, cellSizeZ, clod, cells);
}
}
}
}
//根据Lod生成Mesh
float p = Mathf.Pow(2, maxLod);
float dtx = widthX * 2 / cellSizeX / p;
float dty = widthZ * 2 / cellSizeZ / p;
MeshVertexData cache = new MeshVertexData(cellSizeX * (int)p, cellSizeZ * (int)p, dtx, dty, -widthX, -widthZ);
for (int i = 0; i < cellSizeX; i++)
{
for (int j = 0; j < cellSizeZ; j++)
{
LodMeshCell cell = cells[i, j];
if (cell.lod == -1)
{
continue;
}
int leftLod = i == 0 ? -1 : cells[i - 1, j].lod;
int rightLod = i == cells.GetLength(0) - 1 ? -1 : cells[i + 1, j].lod;
int downLod = j == 0 ? -1 : cells[i, j - 1].lod;
int upLod = j == cells.GetLength(1) - 1 ? -1 : cells[i, j + 1].lod;
cell.SetNeighborLOD(leftLod, rightLod, upLod, downLod);
cell.UpdateMesh(cache);
}
}
//生成网格
Mesh mesh = cache.Apply(texture, uvDir, samples);
return(mesh);
}
