public void ClassifyVoxel(deviceptr <int3> d_gridIdx, deviceptr <float3> d_voxelV, deviceptr <int> d_voxelVerts,
deviceptr <int> d_voxelOccupied, deviceptr <float3> d_samplePts, int sampleLength)
{
int blockId = blockIdx.y * gridDim.x + blockIdx.x; //block在grid中的位置
int i = blockId * blockDim.x + threadIdx.x; //线程索引
// compute 3d index in the grid
int3 gridPos = calcGridPos(i, constGridSize.Value);
d_gridIdx[i] = gridPos;
float3 p = new float3();
p.x = constBasePoint.Value.x + gridPos.x * constVoxelSize.Value.x;
p.y = constBasePoint.Value.y + gridPos.y * constVoxelSize.Value.y;
p.z = constBasePoint.Value.z + gridPos.z * constVoxelSize.Value.z;
// compute all vertices
d_voxelV[i * 8] = p;
d_voxelV[i * 8 + 1] = CreateFloat3(constVoxelSize.Value.x + p.x, 0 + p.y, 0 + p.z);
d_voxelV[i * 8 + 2] = CreateFloat3(constVoxelSize.Value.x + p.x, constVoxelSize.Value.y + p.y, 0 + p.z);
d_voxelV[i * 8 + 3] = CreateFloat3(0 + p.x, constVoxelSize.Value.y + p.y, 0 + p.z);
d_voxelV[i * 8 + 4] = CreateFloat3(0 + p.x, 0 + p.y, constVoxelSize.Value.z + p.z);
d_voxelV[i * 8 + 5] = CreateFloat3(constVoxelSize.Value.x + p.x, 0 + p.y, constVoxelSize.Value.z + p.z);
d_voxelV[i * 8 + 6] = CreateFloat3(constVoxelSize.Value.x + p.x, constVoxelSize.Value.y + p.y, constVoxelSize.Value.z + p.z);
d_voxelV[i * 8 + 7] = CreateFloat3(0 + p.x, constVoxelSize.Value.y + p.y, constVoxelSize.Value.z + p.z);
// compute cube value of each vertex
float d0 = ComputeValue(d_samplePts, d_voxelV[i * 8], sampleLength);
float d1 = ComputeValue(d_samplePts, d_voxelV[i * 8 + 1], sampleLength);
float d2 = ComputeValue(d_samplePts, d_voxelV[i * 8 + 2], sampleLength);
float d3 = ComputeValue(d_samplePts, d_voxelV[i * 8 + 3], sampleLength);
float d4 = ComputeValue(d_samplePts, d_voxelV[i * 8 + 4], sampleLength);
float d5 = ComputeValue(d_samplePts, d_voxelV[i * 8 + 5], sampleLength);
float d6 = ComputeValue(d_samplePts, d_voxelV[i * 8 + 6], sampleLength);
float d7 = ComputeValue(d_samplePts, d_voxelV[i * 8 + 7], sampleLength);
// check their status
int cubeindex;
cubeindex = Compact(d0, constIsovalue.Value);
cubeindex += Compact(d1, constIsovalue.Value) * 2;
cubeindex += Compact(d2, constIsovalue.Value) * 4;
cubeindex += Compact(d3, constIsovalue.Value) * 8;
cubeindex += Compact(d4, constIsovalue.Value) * 16;
cubeindex += Compact(d5, constIsovalue.Value) * 32;
cubeindex += Compact(d6, constIsovalue.Value) * 64;
cubeindex += Compact(d7, constIsovalue.Value) * 128;
//find out the number of vertices in each voxel
int numVerts = verticesTable[cubeindex];
d_voxelVerts[i] = numVerts;
if (numVerts > 0)
{
d_voxelOccupied[i] = 1;
}
}
//compute 3d index of each voxel on the grid according to 1d index
private int3 calcGridPos(int i, int3 gridSize)
{
int3 gridPos;
gridPos.z = i / (gridSize.x * gridSize.y);
gridPos.y = i % (gridSize.x * gridSize.y) / gridSize.x;
gridPos.x = i % (gridSize.x * gridSize.y) % gridSize.x;
return(gridPos);
}
// classify all voxels according to their activity
public void ClassifyVoxel(int i, float3[] d_samplePts, int[] d_voxelVerts)
{
//计算grid中的位置
int3 gridPos = calcGridPos(i, constGridSize.Value);
float3 p = new float3();
p.x = constBasePoint.Value.x + gridPos.x * constVoxelSize.Value.x;
p.y = constBasePoint.Value.y + gridPos.y * constVoxelSize.Value.y;
p.z = constBasePoint.Value.z + gridPos.z * constVoxelSize.Value.z;
//输出所有顶点
float3 a0 = p;
float3 a1 = CreateFloat3(constVoxelSize.Value.x + p.x, 0 + p.y, 0 + p.z);
float3 a2 = CreateFloat3(constVoxelSize.Value.x + p.x, constVoxelSize.Value.y + p.y, 0 + p.z);
float3 a3 = CreateFloat3(0 + p.x, constVoxelSize.Value.y + p.y, 0 + p.z);
float3 a4 = CreateFloat3(0 + p.x, 0 + p.y, constVoxelSize.Value.z + p.z);
float3 a5 = CreateFloat3(constVoxelSize.Value.x + p.x, 0 + p.y, constVoxelSize.Value.z + p.z);
float3 a6 = CreateFloat3(constVoxelSize.Value.x + p.x, constVoxelSize.Value.y + p.y, constVoxelSize.Value.z + p.z);
float3 a7 = CreateFloat3(0 + p.x, constVoxelSize.Value.y + p.y, constVoxelSize.Value.z + p.z);
float distance = constVoxelSize.Value.x * constVoxelSize.Value.x +
constVoxelSize.Value.y * constVoxelSize.Value.y + constVoxelSize.Value.z * constVoxelSize.Value.z;
float radius = distance * constFusion.Value;
//计算cube中的8个点对应的value
float d0 = ComputeValue(d_samplePts, a0, d_samplePts.Length, constFusion.Value, radius);
float d1 = ComputeValue(d_samplePts, a1, d_samplePts.Length, constFusion.Value, radius);
float d2 = ComputeValue(d_samplePts, a2, d_samplePts.Length, constFusion.Value, radius);
float d3 = ComputeValue(d_samplePts, a3, d_samplePts.Length, constFusion.Value, radius);
float d4 = ComputeValue(d_samplePts, a4, d_samplePts.Length, constFusion.Value, radius);
float d5 = ComputeValue(d_samplePts, a5, d_samplePts.Length, constFusion.Value, radius);
float d6 = ComputeValue(d_samplePts, a6, d_samplePts.Length, constFusion.Value, radius);
float d7 = ComputeValue(d_samplePts, a7, d_samplePts.Length, constFusion.Value, radius);
//判定它们的状态
int cubeindex;
cubeindex = Compact(d0, constIsovalue.Value);
cubeindex += Compact(d1, constIsovalue.Value) * 2;
cubeindex += Compact(d2, constIsovalue.Value) * 4;
cubeindex += Compact(d3, constIsovalue.Value) * 8;
cubeindex += Compact(d4, constIsovalue.Value) * 16;
cubeindex += Compact(d5, constIsovalue.Value) * 32;
cubeindex += Compact(d6, constIsovalue.Value) * 64;
cubeindex += Compact(d7, constIsovalue.Value) * 128;
//根据表来查出该体素的顶点数
int vertexNum = verticesTable[cubeindex];
d_voxelVerts[i] = vertexNum;
}
// extract isosurface points using GPU
public List <Point3f> runExtractIsoSurfaceGPU()
{
var gpu = Gpu.Default;
// output arguments
float3[] pts = new float3[12 * num_voxelActive];
float3[] d_pts = Gpu.Default.Allocate <float3>(pts);
float3[] d_resultV = Gpu.Default.Allocate <float3>(sumVerts);
float[] d_cubeValues = Gpu.Default.Allocate <float>(8 * num_voxelActive);
// input arguments
float3[] d_samplePts = Gpu.Default.Allocate <float3>(samplePts);
int[] d_verts_scanIdx = Gpu.Default.Allocate <int>(verts_scanIdx);
int[] d_index_voxelActive = Gpu.Default.Allocate <int>(index_voxelActive);
// const values
gpu.Copy(Vertices, constVertices);
gpu.Copy(EdgeDirection, constEdgeDirection);
gpu.Copy(EdgeConnection, constEdgeConnection);
gpu.Copy(Tables.EdgeTable, edgeTable);
gpu.Copy(Tables.TriangleTable_GPU, triangleTable);
float3 baseP = new float3((float)basePoint.X, (float)basePoint.Y, (float)basePoint.Z);
gpu.Copy(baseP, constBasePoint);
gpu.Copy(isoValue, constIsovalue);
gpu.Copy(scale, constScale);
gpu.For(0, num_voxelActive, i =>
{
//计算grid中的位置
int3 gridPos = calcGridPos(d_index_voxelActive[i], constGridSize.Value);
float3 p = new float3();
p.x = constBasePoint.Value.x + gridPos.x * constVoxelSize.Value.x;
p.y = constBasePoint.Value.y + gridPos.y * constVoxelSize.Value.y;
p.z = constBasePoint.Value.z + gridPos.z * constVoxelSize.Value.z;
//输出所有顶点
float3 a0 = p;
float3 a1 = CreateFloat3(constVoxelSize.Value.x + p.x, 0 + p.y, 0 + p.z);
float3 a2 = CreateFloat3(constVoxelSize.Value.x + p.x, constVoxelSize.Value.y + p.y, 0 + p.z);
float3 a3 = CreateFloat3(0 + p.x, constVoxelSize.Value.y + p.y, 0 + p.z);
float3 a4 = CreateFloat3(0 + p.x, 0 + p.y, constVoxelSize.Value.z + p.z);
float3 a5 = CreateFloat3(constVoxelSize.Value.x + p.x, 0 + p.y, constVoxelSize.Value.z + p.z);
float3 a6 = CreateFloat3(constVoxelSize.Value.x + p.x, constVoxelSize.Value.y + p.y, constVoxelSize.Value.z + p.z);
float3 a7 = CreateFloat3(0 + p.x, constVoxelSize.Value.y + p.y, constVoxelSize.Value.z + p.z);
float distance = constVoxelSize.Value.x * constVoxelSize.Value.x +
constVoxelSize.Value.y * constVoxelSize.Value.y + constVoxelSize.Value.z * constVoxelSize.Value.z;
float radius = distance * constFusion.Value;
//Compute cubeValues of 8 vertices
d_cubeValues[i * 8] = ComputeValue(d_samplePts, a0, d_samplePts.Length, constFusion.Value, radius);
d_cubeValues[i * 8 + 1] = ComputeValue(d_samplePts, a1, d_samplePts.Length, constFusion.Value, radius);
d_cubeValues[i * 8 + 2] = ComputeValue(d_samplePts, a2, d_samplePts.Length, constFusion.Value, radius);
d_cubeValues[i * 8 + 3] = ComputeValue(d_samplePts, a3, d_samplePts.Length, constFusion.Value, radius);
d_cubeValues[i * 8 + 4] = ComputeValue(d_samplePts, a4, d_samplePts.Length, constFusion.Value, radius);
d_cubeValues[i * 8 + 5] = ComputeValue(d_samplePts, a5, d_samplePts.Length, constFusion.Value, radius);
d_cubeValues[i * 8 + 6] = ComputeValue(d_samplePts, a6, d_samplePts.Length, constFusion.Value, radius);
d_cubeValues[i * 8 + 7] = ComputeValue(d_samplePts, a7, d_samplePts.Length, constFusion.Value, radius);
//Check each vertex state
int flag = Compact(d_cubeValues[i * 8], constIsovalue.Value);
flag += Compact(d_cubeValues[i * 8 + 1], constIsovalue.Value) * 2;
flag += Compact(d_cubeValues[i * 8 + 2], constIsovalue.Value) * 4;
flag += Compact(d_cubeValues[i * 8 + 3], constIsovalue.Value) * 8;
flag += Compact(d_cubeValues[i * 8 + 4], constIsovalue.Value) * 16;
flag += Compact(d_cubeValues[i * 8 + 5], constIsovalue.Value) * 32;
flag += Compact(d_cubeValues[i * 8 + 6], constIsovalue.Value) * 64;
flag += Compact(d_cubeValues[i * 8 + 7], constIsovalue.Value) * 128;
//find out which edge intersects the isosurface
int EdgeFlag = edgeTable[flag];
//check whether this voxel is crossed by the isosurface
for (int j = 0; j < 12; j++)
{
//check whether an edge have a point
if ((EdgeFlag & (1 << j)) != 0)
{
//compute t values from two end points on each edge
float Offset = GetOffset(d_cubeValues[i * 8 + constEdgeConnection[j * 2 + 0]], d_cubeValues[i * 8 + constEdgeConnection[j * 2 + 1]], constIsovalue.Value);
float3 pt = new float3();
//get positions
pt.x = constBasePoint.Value.x + (gridPos.x + constVertices[constEdgeConnection[j * 2 + 0] * 3 + 0] + Offset * constEdgeDirection[j * 3 + 0]) * constScale.Value;
pt.y = constBasePoint.Value.y + (gridPos.y + constVertices[constEdgeConnection[j * 2 + 0] * 3 + 1] + Offset * constEdgeDirection[j * 3 + 1]) * constScale.Value;
pt.z = constBasePoint.Value.z + (gridPos.z + constVertices[constEdgeConnection[j * 2 + 0] * 3 + 2] + Offset * constEdgeDirection[j * 3 + 2]) * constScale.Value;
d_pts[12 * i + j] = pt;
}
}
int num = 0;
//Find out points from each triangle
for (int Triangle = 0; Triangle < 5; Triangle++)
{
if (triangleTable[flag * 16 + 3 * Triangle] < 0)
{
break;
}
for (int Corner = 0; Corner < 3; Corner++)
{
int Vertex = triangleTable[flag * 16 + 3 * Triangle + Corner];
float3 pd = CreateFloat3(d_pts[12 * i + Vertex].x, d_pts[12 * i + Vertex].y, d_pts[12 * i + Vertex].z);
d_resultV[d_verts_scanIdx[i] + num] = pd;
num++;
}
}
});
resultVerts = Gpu.CopyToHost(d_resultV);
Gpu.Free(d_resultV);
Gpu.Free(d_pts);
Gpu.Free(d_samplePts);
Gpu.Free(d_verts_scanIdx);
Gpu.Free(d_index_voxelActive);
return(ConvertFloat3ToPoint3f(resultVerts));
}
