public static extern bool nmlsGetLayer(IntPtr lset
, int index
, [In, Out] HeightfieldLayer layer);
public static HeightfieldLayerSet buildHeightfieldLayers(Context ctx, CompactHeightfield chf, int borderSize, int walkableHeight)
{
ctx.startTimer("RC_TIMER_BUILD_LAYERS");
int w = chf.width;
int h = chf.height;
int[] srcReg = new int[chf.spanCount];
Arrays.fill(srcReg, 0xFF);
int nsweeps = chf.width; // Math.max(chf.width, chf.height);
SweepSpan[] sweeps = new SweepSpan[nsweeps];
for (int i = 0; i < sweeps.Length; i++)
{
sweeps[i] = new SweepSpan();
}
// Partition walkable area into monotone regions.
int[] prevCount = new int[256];
int regId = 0;
// Sweep one line at a time.
for (int y = borderSize; y < h - borderSize; ++y)
{
// Collect spans from this row.
Arrays.fill(prevCount, 0, regId, 0);
int sweepId = 0;
for (int x = borderSize; x < w - borderSize; ++x)
{
CompactCell c = chf.cells[x + y * w];
for (int i = c.index, ni = c.index + c.count; i < ni; ++i)
{
CompactSpan s = chf.spans[i];
if (chf.areas[i] == RecastConstants.RC_NULL_AREA)
{
continue;
}
int sid = 0xFF;
// -x
if (RecastCommon.GetCon(s, 0) != RecastConstants.RC_NOT_CONNECTED)
{
int ax = x + RecastCommon.GetDirOffsetX(0);
int ay = y + RecastCommon.GetDirOffsetY(0);
int ai = chf.cells[ax + ay * w].index + RecastCommon.GetCon(s, 0);
if (chf.areas[ai] != RecastConstants.RC_NULL_AREA && srcReg[ai] != 0xff)
{
sid = srcReg[ai];
}
}
if (sid == 0xff)
{
sid = sweepId++;
sweeps[sid].nei = 0xff;
sweeps[sid].ns = 0;
}
// -y
if (RecastCommon.GetCon(s, 3) != RecastConstants.RC_NOT_CONNECTED)
{
int ax = x + RecastCommon.GetDirOffsetX(3);
int ay = y + RecastCommon.GetDirOffsetY(3);
int ai = chf.cells[ax + ay * w].index + RecastCommon.GetCon(s, 3);
int nr = srcReg[ai];
if (nr != 0xff)
{
// Set neighbour when first valid neighbour is
// encoutered.
if (sweeps[sid].ns == 0)
{
sweeps[sid].nei = nr;
}
if (sweeps[sid].nei == nr)
{
// Update existing neighbour
sweeps[sid].ns++;
prevCount[nr]++;
}
else
{
// This is hit if there is nore than one
// neighbour.
// Invalidate the neighbour.
sweeps[sid].nei = 0xff;
}
}
}
srcReg[i] = sid;
}
}
// Create unique ID.
for (int i = 0; i < sweepId; ++i)
{
// If the neighbour is set and there is only one continuous
// connection to it,
// the sweep will be merged with the previous one, else new
// region is created.
if (sweeps[i].nei != 0xff && prevCount[sweeps[i].nei] == sweeps[i].ns)
{
sweeps[i].id = sweeps[i].nei;
}
else
{
if (regId == 255)
{
throw new Exception("rcBuildHeightfieldLayers: Region ID overflow.");
}
sweeps[i].id = regId++;
}
}
// Remap local sweep ids to region ids.
for (int x = borderSize; x < w - borderSize; ++x)
{
CompactCell c = chf.cells[x + y * w];
for (int i = c.index, ni = c.index + c.count; i < ni; ++i)
{
if (srcReg[i] != 0xff)
{
srcReg[i] = sweeps[srcReg[i]].id;
}
}
}
}
int nregs = regId;
LayerRegion[] regs = new LayerRegion[nregs];
// Construct regions
for (int i = 0; i < nregs; ++i)
{
regs[i] = new LayerRegion(i);
}
// Find region neighbours and overlapping regions.
List <int> lregs = new List <int>();
for (int y = 0; y < h; ++y)
{
for (int x = 0; x < w; ++x)
{
CompactCell c = chf.cells[x + y * w];
lregs.Clear();
for (int i = c.index, ni = c.index + c.count; i < ni; ++i)
{
CompactSpan s = chf.spans[i];
int ri = srcReg[i];
if (ri == 0xff)
{
continue;
}
regs[ri].ymin = Math.Min(regs[ri].ymin, s.y);
regs[ri].ymax = Math.Max(regs[ri].ymax, s.y);
// Collect all region layers.
lregs.Add(ri);
// Update neighbours
for (int dir = 0; dir < 4; ++dir)
{
if (RecastCommon.GetCon(s, dir) != RecastConstants.RC_NOT_CONNECTED)
{
int ax = x + RecastCommon.GetDirOffsetX(dir);
int ay = y + RecastCommon.GetDirOffsetY(dir);
int ai = chf.cells[ax + ay * w].index + RecastCommon.GetCon(s, dir);
int rai = srcReg[ai];
if (rai != 0xff && rai != ri)
{
addUnique(regs[ri].neis, rai);
}
}
}
}
// Update overlapping regions.
for (int i = 0; i < lregs.Count - 1; ++i)
{
for (int j = i + 1; j < lregs.Count; ++j)
{
if (lregs[i] != lregs[j])
{
LayerRegion ri = regs[lregs[i]];
LayerRegion rj = regs[lregs[j]];
addUnique(ri.layers, lregs[j]);
addUnique(rj.layers, lregs[i]);
}
}
}
}
}
// Create 2D layers from regions.
int layerId = 0;
List <int> stack = new List <int>();
for (int i = 0; i < nregs; ++i)
{
LayerRegion root = regs[i];
// Skip already visited.
if (root.layerId != 0xff)
{
continue;
}
// Start search.
root.layerId = layerId;
root.@base = true;
stack.Add(i);
while (stack.Count > 0)
{
// Pop front
LayerRegion reg = regs[stack[0]];
stack.RemoveAt(0);
foreach (int nei in reg.neis)
{
LayerRegion regn = regs[nei];
// Skip already visited.
if (regn.layerId != 0xff)
{
continue;
}
// Skip if the neighbour is overlapping root region.
if (contains(root.layers, nei))
{
continue;
}
// Skip if the height range would become too large.
int ymin = Math.Min(root.ymin, regn.ymin);
int ymax = Math.Max(root.ymax, regn.ymax);
if ((ymax - ymin) >= 255)
{
continue;
}
// Deepen
stack.Add(nei);
// Mark layer id
regn.layerId = layerId;
// Merge current layers to root.
foreach (int layer in regn.layers)
{
addUnique(root.layers, layer);
}
root.ymin = Math.Min(root.ymin, regn.ymin);
root.ymax = Math.Max(root.ymax, regn.ymax);
}
}
layerId++;
}
// Merge non-overlapping regions that are close in height.
int mergeHeight = walkableHeight * 4;
for (int i = 0; i < nregs; ++i)
{
LayerRegion ri = regs[i];
if (!ri.@base)
{
continue;
}
int newId = ri.layerId;
for (;;)
{
int oldId = 0xff;
for (int j = 0; j < nregs; ++j)
{
if (i == j)
{
continue;
}
LayerRegion rj = regs[j];
if (!rj.@base)
{
continue;
}
// Skip if the regions are not close to each other.
if (!overlapRange(ri.ymin, ri.ymax + mergeHeight, rj.ymin, rj.ymax + mergeHeight))
{
continue;
}
// Skip if the height range would become too large.
int ymin = Math.Min(ri.ymin, rj.ymin);
int ymax = Math.Max(ri.ymax, rj.ymax);
if ((ymax - ymin) >= 255)
{
continue;
}
// Make sure that there is no overlap when merging 'ri' and
// 'rj'.
bool overlap = false;
// Iterate over all regions which have the same layerId as
// 'rj'
for (int k = 0; k < nregs; ++k)
{
if (regs[k].layerId != rj.layerId)
{
continue;
}
// Check if region 'k' is overlapping region 'ri'
// Index to 'regs' is the same as region id.
if (contains(ri.layers, k))
{
overlap = true;
break;
}
}
// Cannot merge of regions overlap.
if (overlap)
{
continue;
}
// Can merge i and j.
oldId = rj.layerId;
break;
}
// Could not find anything to merge with, stop.
if (oldId == 0xff)
{
break;
}
// Merge
for (int j = 0; j < nregs; ++j)
{
LayerRegion rj = regs[j];
if (rj.layerId == oldId)
{
rj.@base = false;
// Remap layerIds.
rj.layerId = newId;
// Add overlaid layers from 'rj' to 'ri'.
foreach (int layer in rj.layers)
{
addUnique(ri.layers, layer);
}
// Update height bounds.
ri.ymin = Math.Min(ri.ymin, rj.ymin);
ri.ymax = Math.Max(ri.ymax, rj.ymax);
}
}
}
}
// Compact layerIds
int[] remap = new int[256];
// Find number of unique layers.
layerId = 0;
for (int i = 0; i < nregs; ++i)
{
remap[regs[i].layerId] = 1;
}
for (int i = 0; i < 256; ++i)
{
if (remap[i] != 0)
{
remap[i] = layerId++;
}
else
{
remap[i] = 0xff;
}
}
// Remap ids.
for (int i = 0; i < nregs; ++i)
{
regs[i].layerId = remap[regs[i].layerId];
}
// No layers, return empty.
if (layerId == 0)
{
// ctx.stopTimer(RC_TIMER_BUILD_LAYERS);
return(null);
}
// Create layers.
// rcAssert(lset.layers == 0);
int lw = w - borderSize * 2;
int lh = h - borderSize * 2;
// Build contracted bbox for layers.
float[] bmin = new float[3];
float[] bmax = new float[3];
RecastVectors.copy(bmin, chf.bmin);
RecastVectors.copy(bmax, chf.bmax);
bmin[0] += borderSize * chf.cs;
bmin[2] += borderSize * chf.cs;
bmax[0] -= borderSize * chf.cs;
bmax[2] -= borderSize * chf.cs;
HeightfieldLayerSet lset = new HeightfieldLayerSet();
lset.layers = new HeightfieldLayer[layerId];
for (int i = 0; i < lset.layers.Length; i++)
{
lset.layers[i] = new HeightfieldLayer();
}
// Store layers.
for (int i = 0; i < lset.layers.Length; ++i)
{
int curId = i;
HeightfieldLayer layer = lset.layers[i];
int gridSize = lw * lh;
layer.heights = new int[gridSize];
Arrays.fill(layer.heights, 0xFF);
layer.areas = new int[gridSize];
layer.cons = new int[gridSize];
// Find layer height bounds.
int hmin = 0, hmax = 0;
for (int j = 0; j < nregs; ++j)
{
if (regs[j].@base && regs[j].layerId == curId)
{
hmin = regs[j].ymin;
hmax = regs[j].ymax;
}
}
layer.width = lw;
layer.height = lh;
layer.cs = chf.cs;
layer.ch = chf.ch;
// Adjust the bbox to fit the heightfield.
RecastVectors.copy(layer.bmin, bmin);
RecastVectors.copy(layer.bmax, bmax);
layer.bmin[1] = bmin[1] + hmin * chf.ch;
layer.bmax[1] = bmin[1] + hmax * chf.ch;
layer.hmin = hmin;
layer.hmax = hmax;
// Update usable data region.
layer.minx = layer.width;
layer.maxx = 0;
layer.miny = layer.height;
layer.maxy = 0;
// Copy height and area from compact heightfield.
for (int y = 0; y < lh; ++y)
{
for (int x = 0; x < lw; ++x)
{
int cx = borderSize + x;
int cy = borderSize + y;
CompactCell c = chf.cells[cx + cy * w];
for (int j = c.index, nj = c.index + c.count; j < nj; ++j)
{
CompactSpan s = chf.spans[j];
// Skip unassigned regions.
if (srcReg[j] == 0xff)
{
continue;
}
// Skip of does nto belong to current layer.
int lid = regs[srcReg[j]].layerId;
if (lid != curId)
{
continue;
}
// Update data bounds.
layer.minx = Math.Min(layer.minx, x);
layer.maxx = Math.Max(layer.maxx, x);
layer.miny = Math.Min(layer.miny, y);
layer.maxy = Math.Max(layer.maxy, y);
// Store height and area type.
int idx = x + y * lw;
layer.heights[idx] = (char)(s.y - hmin);
layer.areas[idx] = chf.areas[j];
// Check connection.
char portal = (char)0;
char con = (char)0;
for (int dir = 0; dir < 4; ++dir)
{
if (RecastCommon.GetCon(s, dir) != RecastConstants.RC_NOT_CONNECTED)
{
int ax = cx + RecastCommon.GetDirOffsetX(dir);
int ay = cy + RecastCommon.GetDirOffsetY(dir);
int ai = chf.cells[ax + ay * w].index + RecastCommon.GetCon(s, dir);
int alid = srcReg[ai] != 0xff ? regs[srcReg[ai]].layerId : 0xff;
// Portal mask
if (chf.areas[ai] != RecastConstants.RC_NULL_AREA && lid != alid)
{
portal |= (char)(1 << dir);
// Update height so that it matches on both
// sides of the portal.
CompactSpan @as = chf.spans[ai];
if (@as.y > hmin)
{
layer.heights[idx] = Math.Max(layer.heights[idx], (char)(@as.y - hmin));
}
}
// Valid connection mask
if (chf.areas[ai] != RecastConstants.RC_NULL_AREA && lid == alid)
{
int nx = ax - borderSize;
int ny = ay - borderSize;
if (nx >= 0 && ny >= 0 && nx < lw && ny < lh)
{
con |= (char)(1 << dir);
}
}
}
}
layer.cons[idx] = (portal << 4) | con;
}
}
}
if (layer.minx > layer.maxx)
{
layer.minx = layer.maxx = 0;
}
if (layer.miny > layer.maxy)
{
layer.miny = layer.maxy = 0;
}
}
// ctx->stopTimer(RC_TIMER_BUILD_LAYERS);
return(lset);
}
