public void VoxelizeInput(GraphTransform graphTransform, Bounds graphSpaceBounds)
{
AstarProfiler.StartProfile("Build Navigation Mesh");
AstarProfiler.StartProfile("Voxelizing - Step 1");
// Transform from voxel space to graph space.
// then scale from voxel space (one unit equals one voxel)
// Finally add min
PF.Matrix4x4 voxelMatrix = PF.Matrix4x4.TRS(graphSpaceBounds.min, PF.Quaternion.identity, Vector3.one) * PF.Matrix4x4.Scale(new PF.Vector3(cellSize, cellHeight, cellSize));
transformVoxel2Graph = new GraphTransform(voxelMatrix);
// Transform from voxel space to world space
// add half a voxel to fix rounding
transform = graphTransform * voxelMatrix * PF.Matrix4x4.TRS(new Vector3(0.5f, 0, 0.5f), PF.Quaternion.identity, Vector3.one);
int maximumVoxelYCoord = (int)(graphSpaceBounds.size.y / cellHeight);
AstarProfiler.EndProfile("Voxelizing - Step 1");
AstarProfiler.StartProfile("Voxelizing - Step 2 - Init");
// Cosine of the slope limit in voxel space (some tweaks are needed because the voxel space might be stretched out along the y axis)
float slopeLimit = Mathf.Cos(Mathf.Atan(Mathf.Tan(maxSlope * Mathf.Deg2Rad) * (cellSize / cellHeight)));
// Temporary arrays used for rasterization
float[] vTris = new float[3 * 3];
float[] vOut = new float[7 * 3];
float[] vRow = new float[7 * 3];
float[] vCellOut = new float[7 * 3];
float[] vCell = new float[7 * 3];
if (inputMeshes == null)
{
throw new System.NullReferenceException("inputMeshes not set");
}
// Find the largest lengths of vertex arrays and check for meshes which can be skipped
int maxVerts = 0;
for (int m = 0; m < inputMeshes.Count; m++)
{
maxVerts = System.Math.Max(inputMeshes[m].vertices.Length, maxVerts);
}
// Create buffer, here vertices will be stored multiplied with the local-to-voxel-space matrix
var verts = new Vector3[maxVerts];
AstarProfiler.EndProfile("Voxelizing - Step 2 - Init");
AstarProfiler.StartProfile("Voxelizing - Step 2");
// This loop is the hottest place in the whole rasterization process
// it usually accounts for around 50% of the time
for (int m = 0; m < inputMeshes.Count; m++)
{
RasterizationMesh mesh = inputMeshes[m];
var meshMatrix = mesh.matrix;
// Flip the orientation of all faces if the mesh is scaled in such a way
// that the face orientations would change
// This happens for example if a mesh has a negative scale along an odd number of axes
// e.g it happens for the scale (-1, 1, 1) but not for (-1, -1, 1) or (1,1,1)
var flipOrientation = UnityHelper.ReversesFaceOrientations(meshMatrix);
Vector3[] vs = mesh.vertices;
int[] tris = mesh.triangles;
int trisLength = mesh.numTriangles;
// Transform vertices first to world space and then to voxel space
for (int i = 0; i < vs.Length; i++)
{
verts[i] = transform.InverseTransform(meshMatrix.MultiplyPoint3x4(vs[i]));
}
int mesharea = mesh.area;
for (int i = 0; i < trisLength; i += 3)
{
Vector3 p1 = verts[tris[i]];
Vector3 p2 = verts[tris[i + 1]];
Vector3 p3 = verts[tris[i + 2]];
if (flipOrientation)
{
var tmp = p1;
p1 = p3;
p3 = tmp;
}
int minX = (int)(Utility.Min(p1.x, p2.x, p3.x));
int minZ = (int)(Utility.Min(p1.z, p2.z, p3.z));
int maxX = (int)System.Math.Ceiling(Utility.Max(p1.x, p2.x, p3.x));
int maxZ = (int)System.Math.Ceiling(Utility.Max(p1.z, p2.z, p3.z));
minX = Mathf.Clamp(minX, 0, voxelArea.width - 1);
maxX = Mathf.Clamp(maxX, 0, voxelArea.width - 1);
minZ = Mathf.Clamp(minZ, 0, voxelArea.depth - 1);
maxZ = Mathf.Clamp(maxZ, 0, voxelArea.depth - 1);
// Check if the mesh is completely out of bounds
if (minX >= voxelArea.width || minZ >= voxelArea.depth || maxX <= 0 || maxZ <= 0)
{
continue;
}
Vector3 normal;
int area;
//AstarProfiler.StartProfile ("Rasterize...");
normal = Vector3.Cross(p2 - p1, p3 - p1);
float cosSlopeAngle = Vector3.Dot(normal.normalized, Vector3.up);
if (cosSlopeAngle < slopeLimit)
{
area = UnwalkableArea;
}
else
{
area = 1 + mesharea;
}
Utility.CopyVector(vTris, 0, p1);
Utility.CopyVector(vTris, 3, p2);
Utility.CopyVector(vTris, 6, p3);
for (int x = minX; x <= maxX; x++)
{
int nrow = clipper.ClipPolygon(vTris, 3, vOut, 1F, -x + 0.5F, 0);
if (nrow < 3)
{
continue;
}
nrow = clipper.ClipPolygon(vOut, nrow, vRow, -1F, x + 0.5F, 0);
if (nrow < 3)
{
continue;
}
float clampZ1 = vRow[2];
float clampZ2 = vRow[2];
for (int q = 1; q < nrow; q++)
{
float val = vRow[q * 3 + 2];
clampZ1 = System.Math.Min(clampZ1, val);
clampZ2 = System.Math.Max(clampZ2, val);
}
int clampZ1I = Mathf.Clamp((int)System.Math.Round(clampZ1), 0, voxelArea.depth - 1);
int clampZ2I = Mathf.Clamp((int)System.Math.Round(clampZ2), 0, voxelArea.depth - 1);
for (int z = clampZ1I; z <= clampZ2I; z++)
{
//AstarProfiler.StartFastProfile(1);
int ncell = clipper.ClipPolygon(vRow, nrow, vCellOut, 1F, -z + 0.5F, 2);
if (ncell < 3)
{
//AstarProfiler.EndFastProfile(1);
continue;
}
ncell = clipper.ClipPolygonY(vCellOut, ncell, vCell, -1F, z + 0.5F, 2);
if (ncell < 3)
{
//AstarProfiler.EndFastProfile(1);
continue;
}
//AstarProfiler.EndFastProfile(1);
//AstarProfiler.StartFastProfile(2);
float sMin = vCell[1];
float sMax = vCell[1];
for (int q = 1; q < ncell; q++)
{
float val = vCell[q * 3 + 1];
sMin = System.Math.Min(sMin, val);
sMax = System.Math.Max(sMax, val);
}
//AstarProfiler.EndFastProfile(2);
int maxi = (int)System.Math.Ceiling(sMax);
// Skip span if below or above the bounding box
if (maxi >= 0 && sMin <= maximumVoxelYCoord)
{
// Make sure mini >= 0
int mini = System.Math.Max(0, (int)sMin);
// Make sure the span is at least 1 voxel high
maxi = System.Math.Max(mini + 1, maxi);
voxelArea.AddLinkedSpan(z * voxelArea.width + x, (uint)mini, (uint)maxi, area, voxelWalkableClimb);
}
}
}
}
//AstarProfiler.EndFastProfile(0);
//AstarProfiler.EndProfile ("Rasterize...");
}
AstarProfiler.EndProfile("Voxelizing - Step 2");
}
