static bool filterSmallRegions(rcContext* ctx, int minRegionArea, int mergeRegionSize, unsigned short& maxRegionId, rcCompactHeightfield& chf, unsigned short* srcReg) { const int w = chf.width; const int h = chf.height; const int nreg = maxRegionId+1; rcRegion* regions = (rcRegion*)rcAlloc(sizeof(rcRegion)*nreg, RC_ALLOC_TEMP); if (!regions) { ctx->log(RC_LOG_ERROR, "filterSmallRegions: Out of memory 'regions' (%d).", nreg); return false; } // Construct regions for (int i = 0; i < nreg; ++i) new(®ions[i]) rcRegion((unsigned short)i); // Find edge of a region and find connections around the contour. for (int y = 0; y < h; ++y) { for (int x = 0; x < w; ++x) { const rcCompactCell& c = chf.cells[x+y*w]; for (int i = (int)c.index, ni = (int)(c.index+c.count); i < ni; ++i) { unsigned short r = srcReg[i]; if (r == 0 || r >= nreg) continue; rcRegion& reg = regions[r]; reg.spanCount++; // Update floors. for (int j = (int)c.index; j < ni; ++j) { if (i == j) continue; unsigned short floorId = srcReg[j]; if (floorId == 0 || floorId >= nreg) continue; addUniqueFloorRegion(reg, floorId); } // Have found contour if (reg.connections.size() > 0) continue; reg.areaType = chf.areas[i]; // Check if this cell is next to a border. int ndir = -1; for (int dir = 0; dir < 4; ++dir) { if (isSolidEdge(chf, srcReg, x, y, i, dir)) { ndir = dir; break; } } if (ndir != -1) { // The cell is at border. // Walk around the contour to find all the neighbours. walkContour(x, y, i, ndir, chf, srcReg, reg.connections); } } } } // Remove too small regions. rcIntArray stack(32); rcIntArray trace(32); for (int i = 0; i < nreg; ++i) { rcRegion& reg = regions[i]; if (reg.id == 0 || (reg.id & RC_BORDER_REG)) continue; if (reg.spanCount == 0) continue; if (reg.visited) continue; // Count the total size of all the connected regions. // Also keep track of the regions connects to a tile border. bool connectsToBorder = false; int spanCount = 0; stack.resize(0); trace.resize(0); reg.visited = true; stack.push(i); while (stack.size()) { // Pop int ri = stack.pop(); rcRegion& creg = regions[ri]; spanCount += creg.spanCount; trace.push(ri); for (int j = 0; j < creg.connections.size(); ++j) { if (creg.connections[j] & RC_BORDER_REG) { connectsToBorder = true; continue; } rcRegion& neireg = regions[creg.connections[j]]; if (neireg.visited) continue; if (neireg.id == 0 || (neireg.id & RC_BORDER_REG)) continue; // Visit stack.push(neireg.id); neireg.visited = true; } } // If the accumulated regions size is too small, remove it. // Do not remove areas which connect to tile borders // as their size cannot be estimated correctly and removing them // can potentially remove necessary areas. if (spanCount < minRegionArea && !connectsToBorder) { // Kill all visited regions. for (int j = 0; j < trace.size(); ++j) { regions[trace[j]].spanCount = 0; regions[trace[j]].id = 0; } } } // Merge too small regions to neighbour regions. int mergeCount = 0 ; do { mergeCount = 0; for (int i = 0; i < nreg; ++i) { rcRegion& reg = regions[i]; if (reg.id == 0 || (reg.id & RC_BORDER_REG)) continue; if (reg.spanCount == 0) continue; // Check to see if the region should be merged. if (reg.spanCount > mergeRegionSize && isRegionConnectedToBorder(reg)) continue; // Small region with more than 1 connection. // Or region which is not connected to a border at all. // Find smallest neighbour region that connects to this one. int smallest = 0xfffffff; unsigned short mergeId = reg.id; for (int j = 0; j < reg.connections.size(); ++j) { if (reg.connections[j] & RC_BORDER_REG) continue; rcRegion& mreg = regions[reg.connections[j]]; if (mreg.id == 0 || (mreg.id & RC_BORDER_REG)) continue; if (mreg.spanCount < smallest && canMergeWithRegion(reg, mreg) && canMergeWithRegion(mreg, reg)) { smallest = mreg.spanCount; mergeId = mreg.id; } } // Found new id. if (mergeId != reg.id) { unsigned short oldId = reg.id; rcRegion& target = regions[mergeId]; // Merge neighbours. if (mergeRegions(target, reg)) { // Fixup regions pointing to current region. for (int j = 0; j < nreg; ++j) { if (regions[j].id == 0 || (regions[j].id & RC_BORDER_REG)) continue; // If another region was already merged into current region // change the nid of the previous region too. if (regions[j].id == oldId) regions[j].id = mergeId; // Replace the current region with the new one if the // current regions is neighbour. replaceNeighbour(regions[j], oldId, mergeId); } mergeCount++; } } } } while (mergeCount > 0); // Compress region Ids. for (int i = 0; i < nreg; ++i) { regions[i].remap = false; if (regions[i].id == 0) continue; // Skip nil regions. if (regions[i].id & RC_BORDER_REG) continue; // Skip external regions. regions[i].remap = true; } unsigned short regIdGen = 0; for (int i = 0; i < nreg; ++i) { if (!regions[i].remap) continue; unsigned short oldId = regions[i].id; unsigned short newId = ++regIdGen; for (int j = i; j < nreg; ++j) { if (regions[j].id == oldId) { regions[j].id = newId; regions[j].remap = false; } } } maxRegionId = regIdGen; // Remap regions. for (int i = 0; i < chf.spanCount; ++i) { if ((srcReg[i] & RC_BORDER_REG) == 0) srcReg[i] = regions[srcReg[i]].id; } for (int i = 0; i < nreg; ++i) regions[i].~rcRegion(); rcFree(regions); return true; }
static void walkContour(int x, int y, int i, int dir, rcCompactHeightfield& chf, unsigned short* srcReg, rcIntArray& cont) { int startDir = dir; int starti = i; const rcCompactSpan& ss = chf.spans[i]; unsigned short curReg = 0; if (rcGetCon(ss, dir) != RC_NOT_CONNECTED) { const int ax = x + rcGetDirOffsetX(dir); const int ay = y + rcGetDirOffsetY(dir); const int ai = (int)chf.cells[ax+ay*chf.width].index + rcGetCon(ss, dir); curReg = srcReg[ai]; } cont.push(curReg); int iter = 0; while (++iter < 40000) { const rcCompactSpan& s = chf.spans[i]; if (isSolidEdge(chf, srcReg, x, y, i, dir)) { // Choose the edge corner unsigned short r = 0; if (rcGetCon(s, dir) != RC_NOT_CONNECTED) { const int ax = x + rcGetDirOffsetX(dir); const int ay = y + rcGetDirOffsetY(dir); const int ai = (int)chf.cells[ax+ay*chf.width].index + rcGetCon(s, dir); r = srcReg[ai]; } if (r != curReg) { curReg = r; cont.push(curReg); } dir = (dir+1) & 0x3; // Rotate CW } else { int ni = -1; const int nx = x + rcGetDirOffsetX(dir); const int ny = y + rcGetDirOffsetY(dir); if (rcGetCon(s, dir) != RC_NOT_CONNECTED) { const rcCompactCell& nc = chf.cells[nx+ny*chf.width]; ni = (int)nc.index + rcGetCon(s, dir); } if (ni == -1) { // Should not happen. return; } x = nx; y = ny; i = ni; dir = (dir+3) & 0x3; // Rotate CCW } if (starti == i && startDir == dir) { break; } } // Remove adjacent duplicates. if (cont.size() > 1) { for (int j = 0; j < cont.size(); ) { int nj = (j+1) % cont.size(); if (cont[j] == cont[nj]) { for (int k = j; k < cont.size()-1; ++k) cont[k] = cont[k+1]; cont.pop(); } else ++j; } } }
static bool filterSmallRegions(int minRegionSize, int mergeRegionSize, unsigned short& maxRegionId, rcCompactHeightfield& chf, unsigned short* src) { const int w = chf.width; const int h = chf.height; int nreg = maxRegionId+1; rcRegion* regions = new rcRegion[nreg]; if (!regions) { if (rcGetLog()) rcGetLog()->log(RC_LOG_ERROR, "filterSmallRegions: Out of memory 'regions' (%d).", nreg); return false; } for (int i = 0; i < nreg; ++i) regions[i].id = (unsigned short)i; // Find edge of a region and find connections around the contour. for (int y = 0; y < h; ++y) { for (int x = 0; x < w; ++x) { const rcCompactCell& c = chf.cells[x+y*w]; for (int i = (int)c.index, ni = (int)(c.index+c.count); i < ni; ++i) { unsigned short r = src[i*2]; if (r == 0 || r >= nreg) continue; rcRegion& reg = regions[r]; reg.count++; // Update floors. for (int j = (int)c.index; j < ni; ++j) { if (i == j) continue; unsigned short floorId = src[j*2]; if (floorId == 0 || floorId >= nreg) continue; addUniqueFloorRegion(reg, floorId); } // Have found contour if (reg.connections.size() > 0) continue; // Check if this cell is next to a border. int ndir = -1; for (int dir = 0; dir < 4; ++dir) { if (isSolidEdge(chf, src, x, y, i, dir)) { ndir = dir; break; } } if (ndir != -1) { // The cell is at border. // Walk around the contour to find all the neighbours. walkContour(x, y, i, ndir, chf, src, reg.connections); } } } } // Remove too small unconnected regions. for (int i = 0; i < nreg; ++i) { rcRegion& reg = regions[i]; if (reg.id == 0 || (reg.id & RC_BORDER_REG)) continue; if (reg.count == 0) continue; if (reg.connections.size() == 1 && reg.connections[0] == 0) { if (reg.count < minRegionSize) { // Non-connected small region, remove. reg.count = 0; reg.id = 0; } } } // Merge too small regions to neighbour regions. int mergeCount = 0 ; do { mergeCount = 0; for (int i = 0; i < nreg; ++i) { rcRegion& reg = regions[i]; if (reg.id == 0 || (reg.id & RC_BORDER_REG)) continue; if (reg.count == 0) continue; // Check to see if the region should be merged. if (reg.count > mergeRegionSize && isRegionConnectedToBorder(reg)) continue; // Small region with more than 1 connection. // Or region which is not connected to a border at all. // Find smallest neighbour region that connects to this one. int smallest = 0xfffffff; unsigned short mergeId = reg.id; for (int j = 0; j < reg.connections.size(); ++j) { if (reg.connections[j] & RC_BORDER_REG) continue; rcRegion& mreg = regions[reg.connections[j]]; if (mreg.id == 0 || (mreg.id & RC_BORDER_REG)) continue; if (mreg.count < smallest && canMergeWithRegion(reg, mreg.id) && canMergeWithRegion(mreg, reg.id)) { smallest = mreg.count; mergeId = mreg.id; } } // Found new id. if (mergeId != reg.id) { unsigned short oldId = reg.id; rcRegion& target = regions[mergeId]; // Merge neighbours. if (mergeRegions(target, reg)) { // Fixup regions pointing to current region. for (int j = 0; j < nreg; ++j) { if (regions[j].id == 0 || (regions[j].id & RC_BORDER_REG)) continue; // If another region was already merged into current region // change the nid of the previous region too. if (regions[j].id == oldId) regions[j].id = mergeId; // Replace the current region with the new one if the // current regions is neighbour. replaceNeighbour(regions[j], oldId, mergeId); } mergeCount++; } } } } while (mergeCount > 0); // Compress region Ids. for (int i = 0; i < nreg; ++i) { regions[i].remap = false; if (regions[i].id == 0) continue; // Skip nil regions. if (regions[i].id & RC_BORDER_REG) continue; // Skip external regions. regions[i].remap = true; } unsigned short regIdGen = 0; for (int i = 0; i < nreg; ++i) { if (!regions[i].remap) continue; unsigned short oldId = regions[i].id; unsigned short newId = ++regIdGen; for (int j = i; j < nreg; ++j) { if (regions[j].id == oldId) { regions[j].id = newId; regions[j].remap = false; } } } maxRegionId = regIdGen; // Remap regions. for (int i = 0; i < chf.spanCount; ++i) { if ((src[i*2] & RC_BORDER_REG) == 0) src[i*2] = regions[src[i*2]].id; } delete [] regions; return true; }
/// @par /// /// See the #rcConfig documentation for more information on the configuration parameters. /// /// @see rcAllocHeightfieldLayerSet, rcCompactHeightfield, rcHeightfieldLayerSet, rcConfig bool rcBuildHeightfieldLayers(rcContext* ctx, rcCompactHeightfield& chf, const int borderSize, const int walkableHeight, rcHeightfieldLayerSet& lset) { rcAssert(ctx); ctx->startTimer(RC_TIMER_BUILD_LAYERS); rcScopedDelete<unsigned short> spanBuf4 = (unsigned short*)rcAlloc(sizeof(unsigned short)*chf.spanCount*4, RC_ALLOC_TEMP); if (!spanBuf4) { ctx->log(RC_LOG_ERROR, "rcBuildHeightfieldLayers: Out of memory 'spanBuf4' (%d).", chf.spanCount*4); return false; } ctx->startTimer(RC_TIMER_BUILD_REGIONS_WATERSHED); unsigned short* srcReg = spanBuf4; if (!rcGatherRegionsNoFilter(ctx, chf, borderSize, spanBuf4)) return false; ctx->stopTimer(RC_TIMER_BUILD_REGIONS_WATERSHED); ctx->startTimer(RC_TIMER_BUILD_REGIONS_FILTER); const int w = chf.width; const int h = chf.height; const int nreg = chf.maxRegions + 1; rcLayerRegion* regions = (rcLayerRegion*)rcAlloc(sizeof(rcLayerRegion)*nreg, RC_ALLOC_TEMP); if (!regions) { ctx->log(RC_LOG_ERROR, "rcBuildHeightfieldLayers: Out of memory 'regions' (%d).", nreg); return false; } // Construct regions memset(regions, 0, sizeof(rcLayerRegion)*nreg); for (int i = 0; i < nreg; ++i) { regions[i].layerId = (unsigned short)i; regions[i].ymax = 0; regions[i].ymin = 0xffff; } // Find region neighbours and overlapping regions. for (int y = 0; y < h; ++y) { for (int x = 0; x < w; ++x) { const rcCompactCell& c = chf.cells[x+y*w]; for (int i = (int)c.index, ni = (int)(c.index+c.count); i < ni; ++i) { const rcCompactSpan& s = chf.spans[i]; const unsigned short ri = srcReg[i]; if (ri == 0 || ri >= nreg) continue; rcLayerRegion& reg = regions[ri]; reg.ymin = rcMin(reg.ymin, s.y); reg.ymax = rcMax(reg.ymax, s.y); reg.hasSpans = true; // Collect all region layers. for (int j = (int)c.index; j < ni; ++j) { unsigned short nri = srcReg[j]; if (nri == 0 || nri >= nreg) continue; if (nri != ri) { addUniqueLayerRegion(reg, nri); } } // Have found contour if (reg.connections.size() > 0) continue; // Check if this cell is next to a border. int ndir = -1; for (int dir = 0; dir < 4; ++dir) { if (isSolidEdge(chf, srcReg, x, y, i, dir)) { ndir = dir; break; } } if (ndir != -1) { // The cell is at border. // Walk around the contour to find all the neighbors. walkContour(x, y, i, ndir, chf, srcReg, reg.connections); } } } } // Create 2D layers from regions. unsigned short layerId = 0; rcIntArray stack(64); for (int i = 0; i < nreg; i++) { rcLayerRegion& reg = regions[i]; if (reg.visited || !reg.hasSpans) continue; reg.layerId = layerId; reg.visited = true; reg.base = true; stack.resize(0); stack.push(i); while (stack.size()) { int ri = stack.pop(); rcLayerRegion& creg = regions[ri]; for (int j = 0; j < creg.connections.size(); j++) { const unsigned short nei = (unsigned short)creg.connections[j]; if (nei & RC_BORDER_REG) continue; rcLayerRegion& regn = regions[nei]; // Skip already visited. if (regn.visited) continue; // Skip if the neighbor is overlapping root region. if (reg.layers.contains(nei)) continue; // Skip if the height range would become too large. const int ymin = rcMin(reg.ymin, regn.ymin); const int ymax = rcMin(reg.ymax, regn.ymax); if ((ymax - ymin) >= 255) continue; // visit stack.push(nei); regn.visited = true; regn.layerId = layerId; // add layers to root for (int k = 0; k < regn.layers.size(); k++) addUniqueLayerRegion(reg, regn.layers[k]); reg.ymin = rcMin(reg.ymin, regn.ymin); reg.ymax = rcMax(reg.ymax, regn.ymax); } } layerId++; } // Merge non-overlapping regions that are close in height. const unsigned short mergeHeight = (unsigned short)walkableHeight * 4; for (int i = 0; i < nreg; i++) { rcLayerRegion& ri = regions[i]; if (!ri.base) continue; unsigned short newId = ri.layerId; for (;;) { unsigned short oldId = 0xffff; for (int j = 0; j < nreg; j++) { if (i == j) continue; rcLayerRegion& rj = regions[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. const int ymin = rcMin(ri.ymin, rj.ymin); const int ymax = rcMin(ri.ymax, rj.ymax); if ((ymax - ymin) >= 255) continue; // Make sure that there is no overlap when mergin 'ri' and 'rj'. bool overlap = false; // Iterate over all regions which have the same layerId as 'rj' for (int k = 0; k < nreg; ++k) { if (regions[k].layerId != rj.layerId) continue; // Check if region 'k' is overlapping region 'ri' // Index to 'regs' is the same as region id. if (ri.layers.contains(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 == 0xffff) break; // Merge for (int j = 0; j < nreg; ++j) { rcLayerRegion& rj = regions[j]; if (rj.layerId == oldId) { rj.base = 0; // Remap layerIds. rj.layerId = newId; // Add overlaid layers from 'rj' to 'ri'. for (int k = 0; k < rj.layers.size(); ++k) addUniqueLayerRegion(ri, rj.layers[k]); // Update height bounds. ri.ymin = rcMin(ri.ymin, rj.ymin); ri.ymax = rcMax(ri.ymax, rj.ymax); } } } } // Compress layer Ids. for (int i = 0; i < nreg; ++i) { regions[i].remap = regions[i].hasSpans; if (!regions[i].hasSpans) { regions[i].layerId = 0xffff; } } unsigned short maxLayerId = 0; for (int i = 0; i < nreg; ++i) { if (!regions[i].remap) continue; unsigned short oldId = regions[i].layerId; unsigned short newId = maxLayerId; for (int j = i; j < nreg; ++j) { if (regions[j].layerId == oldId) { regions[j].layerId = newId; regions[j].remap = false; } } maxLayerId++; } ctx->stopTimer(RC_TIMER_BUILD_REGIONS_FILTER); if (maxLayerId == 0) { ctx->stopTimer(RC_TIMER_BUILD_LAYERS); return true; } // Create layers. rcAssert(lset.layers == 0); const int lw = w - borderSize*2; const int lh = h - borderSize*2; // Build contracted bbox for layers. float bmin[3], bmax[3]; rcVcopy(bmin, chf.bmin); rcVcopy(bmax, chf.bmax); bmin[0] += borderSize*chf.cs; bmin[2] += borderSize*chf.cs; bmax[0] -= borderSize*chf.cs; bmax[2] -= borderSize*chf.cs; lset.nlayers = (int)maxLayerId; lset.layers = (rcHeightfieldLayer*)rcAlloc(sizeof(rcHeightfieldLayer)*lset.nlayers, RC_ALLOC_PERM); if (!lset.layers) { ctx->log(RC_LOG_ERROR, "rcBuildHeightfieldLayers: Out of memory 'layers' (%d).", lset.nlayers); return false; } memset(lset.layers, 0, sizeof(rcHeightfieldLayer)*lset.nlayers); // Store layers. for (int i = 0; i < lset.nlayers; ++i) { unsigned short curId = (unsigned short)i; // Allocate memory for the current layer. rcHeightfieldLayer* layer = &lset.layers[i]; memset(layer, 0, sizeof(rcHeightfieldLayer)); const int gridSize = sizeof(unsigned char)*lw*lh; layer->heights = (unsigned char*)rcAlloc(gridSize, RC_ALLOC_PERM); if (!layer->heights) { ctx->log(RC_LOG_ERROR, "rcBuildHeightfieldLayers: Out of memory 'heights' (%d).", gridSize); return false; } memset(layer->heights, 0xff, gridSize); layer->areas = (unsigned char*)rcAlloc(gridSize, RC_ALLOC_PERM); if (!layer->areas) { ctx->log(RC_LOG_ERROR, "rcBuildHeightfieldLayers: Out of memory 'areas' (%d).", gridSize); return false; } memset(layer->areas, 0, gridSize); layer->cons = (unsigned char*)rcAlloc(gridSize, RC_ALLOC_PERM); if (!layer->cons) { ctx->log(RC_LOG_ERROR, "rcBuildHeightfieldLayers: Out of memory 'cons' (%d).", gridSize); return false; } memset(layer->cons, 0, gridSize); // Find layer height bounds. int hmin = 0, hmax = 0; for (int j = 0; j < nreg; ++j) { if (regions[j].base && regions[j].layerId == curId) { hmin = (int)regions[j].ymin; hmax = (int)regions[j].ymax; } } layer->width = lw; layer->height = lh; layer->cs = chf.cs; layer->ch = chf.ch; // Adjust the bbox to fit the heighfield. rcVcopy(layer->bmin, bmin); rcVcopy(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 heighfield. for (int y = 0; y < lh; ++y) { for (int x = 0; x < lw; ++x) { const int cx = borderSize+x; const int cy = borderSize+y; const rcCompactCell& c = chf.cells[cx+cy*w]; for (int j = (int)c.index, nj = (int)(c.index+c.count); j < nj; ++j) { const rcCompactSpan& s = chf.spans[j]; // Skip unassigned regions. if (srcReg[j] == 0 || srcReg[j] >= nreg) continue; // Skip of does not belong to current layer. unsigned short lid = regions[srcReg[j]].layerId; if (lid != curId) continue; // Update data bounds. layer->minx = rcMin(layer->minx, x); layer->maxx = rcMax(layer->maxx, x); layer->miny = rcMin(layer->miny, y); layer->maxy = rcMax(layer->maxy, y); // Store height and area type. const int idx = x+y*lw; layer->heights[idx] = (unsigned char)(s.y - hmin); layer->areas[idx] = chf.areas[j]; // Check connection. unsigned char portal = 0; unsigned char con = 0; for (int dir = 0; dir < 4; ++dir) { if (rcGetCon(s, dir) != RC_NOT_CONNECTED) { const int ax = cx + rcGetDirOffsetX(dir); const int ay = cy + rcGetDirOffsetY(dir); const int ai = (int)chf.cells[ax+ay*w].index + rcGetCon(s, dir); unsigned short alid = (srcReg[ai] < nreg) ? regions[srcReg[ai]].layerId : 0xffff; // Portal mask if (chf.areas[ai] != RC_NULL_AREA && lid != alid) { portal |= (unsigned char)(1<<dir); // Update height so that it matches on both sides of the portal. const rcCompactSpan& as = chf.spans[ai]; if (as.y > hmin) layer->heights[idx] = rcMax(layer->heights[idx], (unsigned char)(as.y - hmin)); } // Valid connection mask if (chf.areas[ai] != RC_NULL_AREA && lid == alid) { const int nx = ax - borderSize; const int ny = ay - borderSize; if (nx >= 0 && ny >= 0 && nx < lw && ny < lh) con |= (unsigned 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 true; }
static dtStatus filterSmallRegions(dtTileCacheAlloc* alloc, dtTileCacheLayer& layer, int minRegionArea, int mergeRegionSize, unsigned short& maxRegionId, unsigned short* srcReg) { const int w = (int)layer.header->width; const int h = (int)layer.header->height; const int nreg = maxRegionId+1; dtFixedArray<dtLayerRegion> regions(alloc, nreg); if (!regions) { return DT_FAILURE | DT_OUT_OF_MEMORY; } // Construct regions regions.set(0); for (int i = 0; i < nreg; ++i) regions[i] = dtLayerRegion((unsigned short)i); // Find edge of a region and find connections around the contour. for (int y = 0; y < h; ++y) { const bool borderY = (y == 0) || (y == (h - 1)); for (int x = 0; x < w; ++x) { const int i = x+y*w; unsigned short r = srcReg[i]; if (r == DT_TILECACHE_NULL_AREA || r >= nreg) continue; dtLayerRegion& reg = regions[r]; reg.cellCount++; reg.border |= borderY || (x == 0) || (x == (w - 1)); // Have found contour if (reg.connections.size() > 0) continue; reg.areaType = layer.areas[i]; // Check if this cell is next to a border. int ndir = -1; for (int dir = 0; dir < 4; ++dir) { if (isSolidEdge(layer, srcReg, x, y, i, dir)) { ndir = dir; break; } } if (ndir != -1) { // The cell is at border. // Walk around the contour to find all the neighbours. walkContour(x, y, i, ndir, layer, srcReg, reg.connections); } } } // Remove too small regions. dtIntArray stack(32); dtIntArray trace(32); for (int i = 0; i < nreg; ++i) { dtLayerRegion& reg = regions[i]; if (reg.id == 0) continue; if (reg.cellCount == 0) continue; if (reg.visited) continue; // Count the total size of all the connected regions. // Also keep track of the regions connects to a tile border. bool connectsToBorder = false; int cellCount = 0; stack.resize(0); trace.resize(0); reg.visited = true; stack.push(i); while (stack.size()) { // Pop int ri = stack.pop(); dtLayerRegion& creg = regions[ri]; connectsToBorder |= creg.border; cellCount += creg.cellCount; trace.push(ri); for (int j = 0; j < creg.connections.size(); ++j) { dtLayerRegion& neireg = regions[creg.connections[j]]; if (neireg.visited) continue; if (neireg.id == 0) continue; // Visit stack.push(neireg.id); neireg.visited = true; } } // If the accumulated regions size is too small, remove it. // Do not remove areas which connect to tile borders // as their size cannot be estimated correctly and removing them // can potentially remove necessary areas. if (cellCount < minRegionArea && !connectsToBorder) { // Kill all visited regions. for (int j = 0; j < trace.size(); ++j) { regions[trace[j]].cellCount = 0; regions[trace[j]].id = 0; } } } // Merge too small regions to neighbour regions. int mergeCount = 0 ; do { mergeCount = 0; for (int i = 0; i < nreg; ++i) { dtLayerRegion& reg = regions[i]; if (reg.id == 0) continue; if (reg.cellCount == 0) continue; // Check to see if the region should be merged. if (reg.cellCount > mergeRegionSize && reg.border) continue; // Small region with more than 1 connection. // Or region which is not connected to a border at all. // Find smallest neighbour region that connects to this one. int smallest = 0xfffffff; unsigned short mergeId = reg.id; for (int j = 0; j < reg.connections.size(); ++j) { dtLayerRegion& mreg = regions[reg.connections[j]]; if (mreg.id == 0) continue; if (mreg.cellCount < smallest && canMergeWithRegion(reg, mreg) && canMergeWithRegion(mreg, reg)) { smallest = mreg.cellCount; mergeId = mreg.id; } } // Found new id. if (mergeId != reg.id) { unsigned short oldId = reg.id; dtLayerRegion& target = regions[mergeId]; // Merge neighbours. if (mergeRegions(target, reg)) { // Fixup regions pointing to current region. for (int j = 0; j < nreg; ++j) { if (regions[j].id == 0) continue; // If another region was already merged into current region // change the nid of the previous region too. if (regions[j].id == oldId) regions[j].id = mergeId; // Replace the current region with the new one if the // current regions is neighbour. replaceNeighbour(regions[j], oldId, mergeId); } mergeCount++; } } } } while (mergeCount > 0); // Compress region Ids. for (int i = 0; i < nreg; ++i) { regions[i].remap = false; if (regions[i].id == DT_TILECACHE_NULL_AREA) continue; // Skip nil regions. regions[i].remap = true; } unsigned short regIdGen = 0; for (int i = 0; i < nreg; ++i) { if (!regions[i].remap) continue; unsigned short oldId = regions[i].id; unsigned short newId = ++regIdGen; for (int j = i; j < nreg; ++j) { if (regions[j].id == oldId) { regions[j].id = newId; regions[j].remap = false; } } } maxRegionId = regIdGen; // Remap regions. for (int i = w*h-1; i >= 0; i--) { srcReg[i] = regions[srcReg[i]].id; } for (int i = 0; i < nreg; ++i) regions[i].~dtLayerRegion(); return DT_SUCCESS; }