2524 lines
62 KiB
C++

//
// Copyright (c) 2009-2010 Mikko Mononen memon@inside.org
//
// This software is provided 'as-is', without any express or implied
// warranty. In no event will the authors be held liable for any damages
// arising from the use of this software.
// Permission is granted to anyone to use this software for any purpose,
// including commercial applications, and to alter it and redistribute it
// freely, subject to the following restrictions:
// 1. The origin of this software must not be misrepresented; you must not
// claim that you wrote the original software. If you use this software
// in a product, an acknowledgment in the product documentation would be
// appreciated but is not required.
// 2. Altered source versions must be plainly marked as such, and must not be
// misrepresented as being the original software.
// 3. This notice may not be removed or altered from any source distribution.
//
#include <float.h>
#define _USE_MATH_DEFINES
#include <math.h>
#include <string.h>
#include <stdlib.h>
#include <stdio.h>
#include "Recast.h"
#include "RecastAlloc.h"
#include "RecastAssert.h"
static const int RC_MAX_LAYERS = RC_NOT_CONNECTED;
static const int RC_MAX_NEIS = 16;
struct rcLayerRegion
{
unsigned char layers[RC_MAX_LAYERS];
unsigned char neis[RC_MAX_NEIS];
unsigned short ymin, ymax;
unsigned short count;
unsigned char layerId;
unsigned char nlayers;
unsigned char nneis;
unsigned char start;
};
static void addUnique(unsigned char* a, unsigned char& an, unsigned char v)
{
const int n = (int)an;
for (int i = 0; i < n; ++i)
if (a[i] == v)
return;
a[an] = v;
an++;
}
static void addUniqueLast(unsigned char* a, unsigned char& an, unsigned char v)
{
const int n = (int)an;
if (n > 0 && a[n-1] == v) return;
a[an] = v;
an++;
}
static bool contains(const unsigned char* a, const unsigned char an, const unsigned char v)
{
const int n = (int)an;
for (int i = 0; i < n; ++i)
if (a[i] == v)
return true;
return false;
}
inline bool overlapRange(const unsigned short amin, const unsigned short amax,
const unsigned short bmin, const unsigned short bmax)
{
return (amin > bmax || amax < bmin) ? false : true;
}
struct rcLayerSweepSpan
{
unsigned short ns; // number samples
unsigned char id; // region id
unsigned char nei; // neighbour id
};
bool rcBuildHeightfieldLayers(rcContext* ctx, rcCompactHeightfield& chf,
const int borderSize, const int walkableHeight,
rcHeightfieldLayerSet& lset)
{
rcAssert(ctx);
ctx->startTimer(RC_TIMER_BUILD_LAYERS);
const int w = chf.width;
const int h = chf.height;
rcScopedDelete<unsigned char> srcReg = (unsigned char*)rcAlloc(sizeof(unsigned char)*chf.spanCount, RC_ALLOC_TEMP);
if (!srcReg)
{
ctx->log(RC_LOG_ERROR, "rcBuildHeightfieldLayers: Out of memory 'srcReg' (%d).", chf.spanCount);
return false;
}
memset(srcReg,0xff,sizeof(unsigned char)*chf.spanCount);
const int nsweeps = chf.width;
rcScopedDelete<rcLayerSweepSpan> sweeps = (rcLayerSweepSpan*)rcAlloc(sizeof(rcLayerSweepSpan)*nsweeps, RC_ALLOC_TEMP);
if (!sweeps)
{
ctx->log(RC_LOG_ERROR, "rcBuildHeightfieldLayers: Out of memory 'sweeps' (%d).", nsweeps);
return false;
}
// Partition walkable area into monotone regions.
int prevCount[256];
unsigned char regId = 0;
// for (int y = 0; y < h; ++y)
for (int y = borderSize; y < h-borderSize; ++y)
{
memset(prevCount,0,sizeof(int)*regId);
unsigned char sweepId = 0;
// for (int x = 0; x < w; ++x)
for (int x = borderSize; x < w-borderSize; ++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];
if (chf.areas[i] == RC_NULL_AREA) continue;
unsigned char sid = 0xff;
// -x
if (rcGetCon(s, 0) != RC_NOT_CONNECTED)
{
const int ax = x + rcGetDirOffsetX(0);
const int ay = y + rcGetDirOffsetY(0);
const int ai = (int)chf.cells[ax+ay*w].index + rcGetCon(s, 0);
if (chf.areas[ai] != RC_NULL_AREA && srcReg[ai] != 0xff)
sid = srcReg[ai];
}
if (sid == 0xff)
{
sid = sweepId++;
sweeps[sid].nei = 0xff;
sweeps[sid].ns = 0;
}
// -y
if (rcGetCon(s,3) != RC_NOT_CONNECTED)
{
const int ax = x + rcGetDirOffsetX(3);
const int ay = y + rcGetDirOffsetY(3);
const int ai = (int)chf.cells[ax+ay*w].index + rcGetCon(s, 3);
const unsigned char 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] == (int)sweeps[i].ns)
{
sweeps[i].id = sweeps[i].nei;
}
else
{
if (regId == 255)
{
ctx->log(RC_LOG_ERROR, "rcBuildHeightfieldLayers: Region ID overflow.");
return false;
}
sweeps[i].id = regId++;
}
}
// Remap local sweep ids to region ids.
// for (int x = 0; x < w; ++x)
for (int x = borderSize; x < w-borderSize; ++x)
{
const rcCompactCell& c = chf.cells[x+y*w];
for (int i = (int)c.index, ni = (int)(c.index+c.count); i < ni; ++i)
{
if (srcReg[i] != 0xff)
srcReg[i] = sweeps[srcReg[i]].id;
}
}
}
// Allocate and init layer regions.
const int nregs = (int)regId;
rcScopedDelete<rcLayerRegion> regs = (rcLayerRegion*)rcAlloc(sizeof(rcLayerRegion)*nregs, RC_ALLOC_TEMP);
if (!regs)
{
ctx->log(RC_LOG_ERROR, "rcBuildHeightfieldLayers: Out of memory 'regs' (%d).", nregs);
return false;
}
memset(regs, 0, sizeof(rcLayerRegion)*nregs);
for (int i = 0; i < nregs; ++i)
{
regs[i].layerId = 0xff;
regs[i].ymin = 0xffff;
regs[i].ymax = 0;
}
// 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];
unsigned char lregs[RC_MAX_LAYERS];
int nlregs = 0;
for (int i = (int)c.index, ni = (int)(c.index+c.count); i < ni; ++i)
{
const rcCompactSpan& s = chf.spans[i];
const unsigned char ri = srcReg[i];
if (ri == 0xff) continue;
regs[ri].ymin = rcMin(regs[ri].ymin, s.y);
regs[ri].ymax = rcMax(regs[ri].ymax, s.y);
// Collect all region layers.
if (nlregs < RC_MAX_LAYERS)
lregs[nlregs++] = ri;
// Update neighbours
for (int dir = 0; dir < 4; ++dir)
{
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*w].index + rcGetCon(s, dir);
const unsigned char rai = srcReg[ai];
if (rai != 0xff && rai != ri)
addUnique(regs[ri].neis, regs[ri].nneis, rai);
}
}
}
// Update overlapping regions.
for (int i = 0; i < nlregs-1; ++i)
{
for (int j = i+1; j < nlregs; ++j)
{
if (lregs[i] != lregs[j])
{
rcLayerRegion& ri = regs[lregs[i]];
rcLayerRegion& rj = regs[lregs[j]];
addUnique(ri.layers, ri.nlayers, lregs[j]);
addUnique(rj.layers, rj.nlayers, lregs[i]);
}
}
}
}
}
// Create 2D layers from regions.
unsigned char layerId = 0;
static const int MAX_STACK = 64;
unsigned char stack[MAX_STACK];
int nstack = 0;
for (int i = 0; i < nregs; ++i)
{
rcLayerRegion& root = regs[i];
// Skip alreadu visited.
if (root.layerId != 0xff)
continue;
// Start search.
root.layerId = layerId;
root.start = 1;
nstack = 0;
stack[nstack++] = (unsigned char)i;
while (nstack)
{
// Pop front
rcLayerRegion& reg = regs[stack[0]];
nstack--;
for (int j = 0; j < nstack; ++j)
stack[j] = stack[j+1];
const int nneis = (int)reg.nneis;
for (int j = 0; j < nneis; ++j)
{
const unsigned char nei = reg.neis[j];
rcLayerRegion& regn = regs[nei];
// Skip already visited.
if (regn.layerId != 0xff)
continue;
// Skip if the neighbour is overlapping root region.
if (contains(root.layers, root.nlayers, nei))
continue;
// Skip if the height range would become too large.
const int ymin = rcMin(root.ymin, regn.ymin);
const int ymax = rcMin(root.ymax, regn.ymax);
if ((ymax - ymin) >= 255)
continue;
if (nstack < MAX_STACK)
{
// Deepen
stack[nstack++] = (unsigned char)nei;
// Mark layer id
regn.layerId = layerId;
// Merge current layers to root.
for (int k = 0; k < regn.nlayers; ++k)
addUnique(root.layers, root.nlayers, regn.layers[k]);
root.ymin = rcMin(root.ymin, regn.ymin);
root.ymax = rcMax(root.ymax, regn.ymax);
}
}
}
layerId++;
}
// Merge non-overlapping regions that are close in height.
const int mergeHeight = walkableHeight * 4;
for (int i = 0; i < nregs; ++i)
{
rcLayerRegion& ri = regs[i];
if (!ri.start) continue;
unsigned char newId = ri.layerId;
for (;;)
{
unsigned char oldId = 0xff;
for (int j = 0; j < nregs; ++j)
{
if (i == j) continue;
rcLayerRegion& rj = regs[j];
if (!rj.start) continue;
// Skip if teh 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 < 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,ri.nlayers, (unsigned char)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)
{
rcLayerRegion& rj = regs[j];
if (rj.layerId == oldId)
{
rj.start = 0;
// Remap layerIds.
rj.layerId = newId;
// Add overlaid layers from 'rj' to 'ri'.
for (int k = 0; k < rj.nlayers; ++k)
addUnique(ri.layers, ri.nlayers, rj.layers[k]);
// Update heigh bounds.
ri.ymin = rcMin(ri.ymin, rj.ymin);
ri.ymax = rcMax(ri.ymax, rj.ymax);
}
}
}
}
// Compact layerIds
unsigned char remap[256];
memset(remap, 0, 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])
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_REGIONS);
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)layerId;
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 char curId = (unsigned char)i;
// Allocate memory for the current layer.
rcHeightfieldLayer* layer = &lset.layers[i];
layer->width = lw;
layer->height = lh;
layer->cs = chf.cs;
layer->ch = chf.ch;
layer->heights = (unsigned char*)rcAlloc(sizeof(unsigned char)*lw*lh, RC_ALLOC_PERM);
if (!layer->heights)
{
ctx->log(RC_LOG_ERROR, "rcBuildHeightfieldLayers: Out of memory 'heights' (%d).", w*h);
return false;
}
memset(layer->heights, 0xff, sizeof(unsigned char)*lw*lh);
layer->areas = (unsigned char*)rcAlloc(sizeof(unsigned char)*lw*lh, RC_ALLOC_PERM);
if (!layer->areas)
{
ctx->log(RC_LOG_ERROR, "rcBuildHeightfieldLayers: Out of memory 'areas' (%d).", w*h);
return false;
}
memset(layer->areas, RC_NULL_AREA, sizeof(unsigned char)*lw*lh);
layer->cons = (unsigned char*)rcAlloc(sizeof(unsigned char)*lw*lh, RC_ALLOC_PERM);
if (!layer->cons)
{
ctx->log(RC_LOG_ERROR, "rcBuildHeightfieldLayers: Out of memory 'cons' (%d).", w*h);
return false;
}
memset(layer->cons, 0, sizeof(unsigned char)*lw*lh);
// Find layer height bounds.
int ymin = 0, ymax = 0;
for (int j = 0; j < nregs; ++j)
{
if (regs[j].start && regs[j].layerId == curId)
{
ymin = (int)regs[j].ymin;
ymax = (int)regs[j].ymax;
}
}
// Adjust the bbox to fit the heighfield.
rcVcopy(layer->bmin, bmin);
rcVcopy(layer->bmax, bmax);
layer->bmin[1] = bmin[1] + ymin*chf.ch;
layer->bmax[1] = bmin[1] + ymax*chf.ch;
// 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 i = (int)c.index, ni = (int)(c.index+c.count); i < ni; ++i)
{
const rcCompactSpan& s = chf.spans[i];
// Skip unassigned regions.
if (srcReg[i] == 0xff)
continue;
// Skip of does nto belong to current layer.
unsigned char lid = regs[srcReg[i]].layerId;
if (lid != curId)
continue;
// Store height and area type.
const int idx = x+y*lw;
layer->heights[idx] = (unsigned char)(s.y - ymin);
layer->areas[idx] = chf.areas[i];
// 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 char alid = srcReg[ai] != 0xff ? regs[srcReg[ai]].layerId : 0xff;
// Portal mask
if (chf.areas[ai] != RC_NULL_AREA && lid != alid)
portal |= (unsigned char)(1<<dir);
// 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;
}
}
}
}
ctx->stopTimer(RC_TIMER_BUILD_LAYERS);
return true;
}
// Runtime stuff....
struct rcMonotoneRegion
{
int area;
unsigned char neis[RC_MAX_NEIS];
unsigned char nneis;
unsigned char regId;
};
inline bool isConnected(rcHeightfieldLayer& layer, const int ia, const int ib, const int walkableClimb)
{
if (layer.areas[ia] != layer.areas[ib]) return false;
if (rcAbs((int)layer.heights[ia] - (int)layer.heights[ib]) > walkableClimb) return false;
return true;
}
static bool canMerge(unsigned char oldRegId, unsigned char newRegId, const rcMonotoneRegion* regs, const int nregs)
{
int count = 0;
for (int i = 0; i < nregs; ++i)
{
const rcMonotoneRegion& reg = regs[i];
if (reg.regId != oldRegId) continue;
const int nnei = (int)reg.nneis;
for (int j = 0; j < nnei; ++j)
{
if (regs[reg.neis[j]].regId == newRegId)
count++;
}
}
return count == 1;
}
// TODO: move this somewhere else, once the layer meshing is done.
bool rcBuildLayerRegions(rcContext* ctx, rcHeightfieldLayer& layer, const int walkableClimb)
{
rcAssert(ctx);
// ctx->startTimer(RC_TIMER_BUILD_LAYERS);
const int w = layer.width;
const int h = layer.height;
rcAssert(layer.regs == 0);
layer.regs = (unsigned char*)rcAlloc(sizeof(unsigned char)*w*h, RC_ALLOC_TEMP);
if (!layer.regs)
{
ctx->log(RC_LOG_ERROR, "rcBuildHeightfieldLayers: Out of memory 'regs' (%d).", w*h);
return false;
}
memset(layer.regs,0xff,sizeof(unsigned char)*w*h);
const int nsweeps = w;
rcScopedDelete<rcLayerSweepSpan> sweeps = (rcLayerSweepSpan*)rcAlloc(sizeof(rcLayerSweepSpan)*nsweeps, RC_ALLOC_TEMP);
if (!sweeps)
{
ctx->log(RC_LOG_ERROR, "rcBuildHeightfieldLayers: Out of memory 'sweeps' (%d).", nsweeps);
return false;
}
memset(sweeps,0,sizeof(rcLayerSweepSpan)*nsweeps);
// Partition walkable area into monotone regions.
unsigned char prevCount[256];
unsigned char regId = 0;
for (int y = 0; y < h; ++y)
{
if (regId > 0)
memset(prevCount,0,sizeof(unsigned char)*regId);
unsigned char sweepId = 0;
for (int x = 0; x < w; ++x)
{
const int idx = x + y*w;
if (layer.areas[idx] == RC_NULL_AREA) continue;
unsigned char sid = 0xff;
// -x
const int xidx = (x-1)+y*w;
if (x > 0 && isConnected(layer, idx, xidx, walkableClimb))
{
if (layer.regs[xidx] != 0xff)
sid = layer.regs[xidx];
}
if (sid == 0xff)
{
sid = sweepId++;
sweeps[sid].nei = 0xff;
sweeps[sid].ns = 0;
}
// -y
const int yidx = x+(y-1)*w;
if (y > 0 && isConnected(layer, idx, yidx, walkableClimb))
{
const unsigned char nr = layer.regs[yidx];
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;
}
}
}
layer.regs[idx] = 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 && (unsigned short)prevCount[sweeps[i].nei] == sweeps[i].ns)
{
sweeps[i].id = sweeps[i].nei;
}
else
{
if (regId == 255)
{
ctx->log(RC_LOG_ERROR, "rcBuildHeightfieldLayers: Region ID overflow.");
return false;
}
sweeps[i].id = regId++;
}
}
// Remap local sweep ids to region ids.
for (int x = 0; x < w; ++x)
{
const int idx = x+y*w;
if (layer.regs[idx] != 0xff)
layer.regs[idx] = sweeps[layer.regs[idx]].id;
}
}
// Allocate and init layer regions.
const int nregs = (int)regId;
rcScopedDelete<rcMonotoneRegion> regs = (rcMonotoneRegion*)rcAlloc(sizeof(rcMonotoneRegion)*nregs, RC_ALLOC_TEMP);
if (!regs)
{
ctx->log(RC_LOG_ERROR, "rcBuildHeightfieldLayers: Out of memory 'regs' (%d).", nregs);
return false;
}
memset(regs, 0, sizeof(rcMonotoneRegion)*nregs);
for (int i = 0; i < nregs; ++i)
regs[i].regId = 0xff;
// Find region neighbours.
for (int y = 0; y < h; ++y)
{
for (int x = 0; x < w; ++x)
{
const int idx = x+y*w;
const unsigned char ri = layer.regs[idx];
if (ri == 0xff)
continue;
// Update area.
regs[ri].area++;
// Update neighbours
const int ymi = x+(y-1)*w;
if (y > 0 && isConnected(layer, idx, ymi, walkableClimb))
{
const unsigned char rai = layer.regs[ymi];
if (rai != 0xff && rai != ri)
{
addUniqueLast(regs[ri].neis, regs[ri].nneis, rai);
addUniqueLast(regs[rai].neis, regs[rai].nneis, ri);
}
}
}
}
for (int i = 0; i < nregs; ++i)
regs[i].regId = (unsigned char)i;
for (int i = 0; i < nregs; ++i)
{
rcMonotoneRegion& reg = regs[i];
int merge = -1;
int mergea = 0;
for (int j = 0; j < (int)reg.nneis; ++j)
{
const unsigned char nei = reg.neis[j];
rcMonotoneRegion& regn = regs[nei];
if (reg.regId == regn.regId)
continue;
if (regn.area > mergea)
{
if (canMerge(reg.regId, regn.regId, regs, nregs))
{
mergea = regn.area;
merge = (int)nei;
}
}
}
if (merge != -1)
{
const unsigned char oldId = reg.regId;
const unsigned char newId = regs[merge].regId;
for (int j = 0; j < nregs; ++j)
if (regs[j].regId == oldId)
regs[j].regId = newId;
}
}
// Compact ids.
unsigned char remap[256];
memset(remap, 0, 256);
// Find number of unique regions.
regId = 0;
for (int i = 0; i < nregs; ++i)
remap[regs[i].regId] = 1;
for (int i = 0; i < 256; ++i)
if (remap[i])
remap[i] = regId++;
// Remap ids.
for (int i = 0; i < nregs; ++i)
regs[i].regId = remap[regs[i].regId];
layer.regCount = regId;
for (int i = 0; i < w*h; ++i)
{
if (layer.regs[i] != 0xff)
layer.regs[i] = regs[layer.regs[i]].regId;
}
return true;
}
struct rcTempContour
{
inline rcTempContour() : verts(0), poly(0) {}
inline ~rcTempContour() { rcFree(verts); rcFree(poly); }
unsigned char* verts;
int nverts;
int cverts;
unsigned short* poly;
int npoly;
int cpoly;
};
static bool appendVertex(rcTempContour& cont, const int x, const int y, const int z, const int r)
{
// Try to merge with existing segments.
if (cont.nverts > 1)
{
unsigned char* pa = &cont.verts[(cont.nverts-2)*4];
unsigned char* pb = &cont.verts[(cont.nverts-1)*4];
if ((int)pb[3] == r)
{
if (pa[0] == pb[0] && (int)pb[0] == x)
{
// The verts are aligned aling x-axis, update z.
pb[1] = (unsigned char)y;
pb[2] = (unsigned char)z;
return true;
}
else if (pa[2] == pb[2] && (int)pb[2] == z)
{
// The verts are aligned aling z-axis, update x.
pb[0] = (unsigned char)x;
pb[1] = (unsigned char)y;
return true;
}
}
}
// Add new point.
if (cont.nverts+1 > cont.cverts)
return false;
unsigned char* v = &cont.verts[cont.nverts*4];
v[0] = (unsigned char)x;
v[1] = (unsigned char)y;
v[2] = (unsigned char)z;
v[3] = (unsigned char)r;
cont.nverts++;
return true;
}
static unsigned char getNeighbourReg(rcHeightfieldLayer& layer,
const int ax, const int ay, const int dir)
{
const int ia = ax+ay*layer.width;
const unsigned char con = layer.cons[ia] & 0xf;
const unsigned char portal = layer.cons[ia] >> 4;
const unsigned char mask = (unsigned char)(1<<dir);
if ((con & mask) == 0)
{
// No connection, return portal or hard edge.
if (portal & mask)
return 0xfe - dir;
return 0xff;
}
const int bx = ax + rcGetDirOffsetX(dir);
const int by = ay + rcGetDirOffsetY(dir);
const int ib = bx+by*layer.width;
return layer.regs[ib];
}
static bool walkContour(rcHeightfieldLayer& layer, int x, int y, rcTempContour& cont)
{
const int w = layer.width;
const int h = layer.height;
cont.nverts = 0;
int startX = x;
int startY = y;
int startDir = -1;
for (int i = 0; i < 4; ++i)
{
const int dir = (i+3)&3;
unsigned char rn = getNeighbourReg(layer, x, y, dir);
if (rn != layer.regs[x+y*w])
{
startDir = dir;
break;
}
}
if (startDir == -1)
return true;
int dir = startDir;
const int maxIter = w*h;
int iter = 0;
while (iter < maxIter)
{
unsigned char rn = getNeighbourReg(layer, x, y, dir);
int nx = x;
int ny = y;
int ndir = dir;
if (rn != layer.regs[x+y*w])
{
// Solid edge.
int px = x;
int pz = y;
switch(dir)
{
case 0: pz++; break;
case 1: px++; pz++; break;
case 2: px++; break;
}
// Try to merge with previous vertex.
if (!appendVertex(cont, px, (int)layer.heights[x+y*w], pz,rn))
return false;
ndir = (dir+1) & 0x3; // Rotate CW
}
else
{
// Move to next.
nx = x + rcGetDirOffsetX(dir);
ny = y + rcGetDirOffsetY(dir);
ndir = (dir+3) & 0x3; // Rotate CCW
}
if (iter > 0 && x == startX && y == startY && dir == startDir)
break;
x = nx;
y = ny;
dir = ndir;
iter++;
}
// Remove last vertex if it is duplicate of the first one.
unsigned char* pa = &cont.verts[(cont.nverts-1)*4];
unsigned char* pb = &cont.verts[0];
if (pa[0] == pb[0] && pa[2] == pb[2])
cont.nverts--;
return true;
}
static float distancePtSeg(const int x, const int z,
const int px, const int pz,
const int qx, const int qz)
{
float pqx = (float)(qx - px);
float pqz = (float)(qz - pz);
float dx = (float)(x - px);
float dz = (float)(z - pz);
float d = pqx*pqx + pqz*pqz;
float t = pqx*dx + pqz*dz;
if (d > 0)
t /= d;
if (t < 0)
t = 0;
else if (t > 1)
t = 1;
dx = px + t*pqx - x;
dz = pz + t*pqz - z;
return dx*dx + dz*dz;
}
static void simplifyContour(rcTempContour& cont, const float maxError)
{
cont.npoly = 0;
for (int i = 0; i < cont.nverts; ++i)
{
int j = (i+1) % cont.nverts;
// Check for start of a wall segment.
unsigned char ra = cont.verts[j*4+3];
unsigned char rb = cont.verts[i*4+3];
if (ra != rb)
cont.poly[cont.npoly++] = i;
}
if (cont.npoly < 2)
{
// If there is no transitions at all,
// create some initial points for the simplification process.
// Find lower-left and upper-right vertices of the contour.
int llx = cont.verts[0];
int llz = cont.verts[2];
int lli = 0;
int urx = cont.verts[0];
int urz = cont.verts[2];
int uri = 0;
for (int i = 1; i < cont.nverts; ++i)
{
int x = cont.verts[i*4+0];
int z = cont.verts[i*4+2];
if (x < llx || (x == llx && z < llz))
{
llx = x;
llz = z;
lli = i;
}
if (x > urx || (x == urx && z > urz))
{
urx = x;
urz = z;
uri = i;
}
}
cont.npoly = 0;
cont.poly[cont.npoly++] = lli;
cont.poly[cont.npoly++] = uri;
}
// Add points until all raw points are within
// error tolerance to the simplified shape.
for (int i = 0; i < cont.npoly; )
{
int ii = (i+1) % cont.npoly;
const int ai = (int)cont.poly[i];
const int ax = (int)cont.verts[ai*4+0];
const int az = (int)cont.verts[ai*4+2];
const int bi = (int)cont.poly[ii];
const int bx = (int)cont.verts[bi*4+0];
const int bz = (int)cont.verts[bi*4+2];
// Find maximum deviation from the segment.
float maxd = 0;
int maxi = -1;
int ci, cinc, endi;
// Traverse the segment in lexilogical order so that the
// max deviation is calculated similarly when traversing
// opposite segments.
if (bx > ax || (bx == ax && bz > az))
{
cinc = 1;
ci = (ai+cinc) % cont.nverts;
endi = bi;
}
else
{
cinc = cont.nverts-1;
ci = (bi+cinc) % cont.nverts;
endi = ai;
}
// Tessellate only outer edges or edges between areas.
while (ci != endi)
{
float d = distancePtSeg(cont.verts[ci*4+0], cont.verts[ci*4+2], ax, az, bx, bz);
if (d > maxd)
{
maxd = d;
maxi = ci;
}
ci = (ci+cinc) % cont.nverts;
}
// If the max deviation is larger than accepted error,
// add new point, else continue to next segment.
if (maxi != -1 && maxd > (maxError*maxError))
{
cont.npoly++;
for (int j = cont.npoly-1; j > i; --j)
cont.poly[j] = cont.poly[j-1];
cont.poly[i+1] = (unsigned short)maxi;
}
else
{
++i;
}
}
// Remap vertices
int start = 0;
for (int i = 1; i < cont.npoly; ++i)
if (cont.poly[i] < cont.poly[start])
start = i;
cont.nverts = 0;
for (int i = 0; i < cont.npoly; ++i)
{
const int j = (start+i) % cont.npoly;
unsigned char* src = &cont.verts[cont.poly[j]*4];
unsigned char* dst = &cont.verts[cont.nverts*4];
dst[0] = src[0];
dst[1] = src[1];
dst[2] = src[2];
dst[3] = src[3];
cont.nverts++;
}
}
static int getCornerHeight(rcHeightfieldLayer& layer,
const int x, const int y, const int z,
const int walkableClimb,
bool& shouldRemove)
{
const int w = layer.width;
const int h = layer.height;
int n = 0;
unsigned char portal = 0xf;
int height = 0;
for (int dz = -1; dz <= 0; ++dz)
{
for (int dx = -1; dx <= 0; ++dx)
{
const int px = x+dx;
const int pz = z+dz;
if (px >= 0 && pz >= 0 && px < w && pz < h)
{
const int idx = px + pz*w;
const int h = (int)layer.heights[idx];
if (rcAbs(h-y) <= walkableClimb)
{
height = rcMax(height, h);
portal &= (layer.cons[idx] >> 4);
n++;
}
}
}
}
int portalCount = 0;
for (int dir = 0; dir < 4; ++dir)
if (portal & (1<<dir))
portalCount++;
shouldRemove = false;
if (n > 1 && portalCount == 1)
{
shouldRemove = true;
}
return height;
}
// TODO: move this somewhere else, once the layer meshing is done.
bool rcBuildLayerContours(rcContext* ctx,
rcHeightfieldLayer& layer,
const int walkableClimb, const float maxError,
rcLayerContourSet& lcset)
{
rcAssert(ctx);
const int w = layer.width;
const int h = layer.height;
rcAssert(lcset.conts == 0);
rcVcopy(lcset.bmin, layer.bmin);
rcVcopy(lcset.bmax, layer.bmax);
lcset.cs = layer.cs;
lcset.ch = layer.ch;
lcset.nconts = layer.regCount;
lcset.conts = (rcLayerContour*)rcAlloc(sizeof(rcLayerContour)*lcset.nconts, RC_ALLOC_TEMP);
if (!lcset.conts)
{
ctx->log(RC_LOG_ERROR, "rcBuildLayerContours: Out of memory 'conts' (%d).", lcset.nconts);
return false;
}
memset(lcset.conts, 0, sizeof(rcLayerContour)*lcset.nconts);
// Allocate temp buffer for contour tracing.
const int maxTempVerts = (w*h*2)*2; // Twice around the layer.
rcTempContour temp;
temp.nverts = 0;
temp.cverts = maxTempVerts;
temp.npoly = 0;
temp.cpoly = maxTempVerts;
temp.verts = (unsigned char*)rcAlloc(sizeof(unsigned char)*temp.cverts, RC_ALLOC_TEMP);
if (!temp.verts)
{
ctx->log(RC_LOG_ERROR, "rcBuildLayerContours: Out of memory 'temp.verts' (%d).", temp.cverts);
return false;
}
temp.poly = (unsigned short*)rcAlloc(sizeof(unsigned short)*temp.cpoly, RC_ALLOC_TEMP);
if (!temp.poly)
{
ctx->log(RC_LOG_ERROR, "rcBuildLayerContours: Out of memory 'temp.poly' (%d).", temp.cpoly);
return false;
}
// Find contours.
for (int y = 0; y < h; ++y)
{
for (int x = 0; x < w; ++x)
{
const int idx = x+y*w;
const unsigned char ri = layer.regs[idx];
if (ri == 0xff)
continue;
rcLayerContour& cont = lcset.conts[ri];
if (cont.nverts > 0)
continue;
cont.reg = ri;
cont.area = layer.areas[idx];
if (!walkContour(layer, x, y, temp))
{
ctx->log(RC_LOG_ERROR, "rcBuildLayerContours: Failed to walk contour (nverts=%d cverts=%d).", temp.nverts, temp.cverts);
return false;
}
simplifyContour(temp, maxError);
// Store contour.
cont.nverts = temp.nverts;
if (cont.nverts > 0)
{
cont.verts = (unsigned char*)rcAlloc(sizeof(unsigned char)*4*temp.nverts, RC_ALLOC_PERM);
if (!cont.verts)
{
ctx->log(RC_LOG_ERROR, "rcBuildLayerContours: Out of memory 'cont.verts' (%d).", temp.nverts);
return false;
}
for (int i = 0, j = temp.nverts-1; i < temp.nverts; j=i++)
{
unsigned char* dst = &cont.verts[j*4];
unsigned char* v = &temp.verts[j*4];
unsigned char* vn = &temp.verts[i*4];
unsigned char nei = vn[3]; // The neighbour reg is stored at segment vertex of a segment.
bool shouldRemove = false;
unsigned char h = getCornerHeight(layer, (int)v[0], (int)v[1], (int)v[2], walkableClimb, shouldRemove);
dst[0] = v[0];
dst[1] = h;
dst[2] = v[2];
// Store portal direction and remove status to the fourth component.
dst[3] = 0x0f;
const int dir = 0xfe - (int)nei;
if (dir >= 0 && dir <= 3)
dst[3] = (unsigned char)dir;
if (shouldRemove)
dst[3] |= 0x80;
}
}
}
}
return true;
}
static const int VERTEX_BUCKET_COUNT2 = (1<<8);
inline int computeVertexHash2(int x, int y, int z)
{
const unsigned int h1 = 0x8da6b343; // Large multiplicative constants;
const unsigned int h2 = 0xd8163841; // here arbitrarily chosen primes
const unsigned int h3 = 0xcb1ab31f;
unsigned int n = h1 * x + h2 * y + h3 * z;
return (int)(n & (VERTEX_BUCKET_COUNT2-1));
}
static unsigned short addVertex(unsigned short x, unsigned short y, unsigned short z,
unsigned short* verts, unsigned short* firstVert, unsigned short* nextVert, int& nv)
{
int bucket = computeVertexHash2(x, 0, z);
unsigned short i = firstVert[bucket];
while (i != RC_MESH_NULL_IDX)
{
const unsigned short* v = &verts[i*3];
if (v[0] == x && v[2] == z && (rcAbs(v[1] - y) <= 2))
return i;
i = nextVert[i]; // next
}
// Could not find, create new.
i = nv; nv++;
unsigned short* v = &verts[i*3];
v[0] = x;
v[1] = y;
v[2] = z;
nextVert[i] = firstVert[bucket];
firstVert[bucket] = i;
return (unsigned short)i;
}
struct rcEdge
{
unsigned short vert[2];
unsigned short polyEdge[2];
unsigned short poly[2];
};
static bool buildMeshAdjacency(unsigned short* polys, const int npolys,
const unsigned short* verts, const int nverts,
const int vertsPerPoly, const rcLayerContourSet& lcset)
{
// Based on code by Eric Lengyel from:
// http://www.terathon.com/code/edges.php
int maxEdgeCount = npolys*vertsPerPoly;
unsigned short* firstEdge = (unsigned short*)rcAlloc(sizeof(unsigned short)*(nverts + maxEdgeCount), RC_ALLOC_TEMP);
if (!firstEdge)
return false;
unsigned short* nextEdge = firstEdge + nverts;
int edgeCount = 0;
rcEdge* edges = (rcEdge*)rcAlloc(sizeof(rcEdge)*maxEdgeCount, RC_ALLOC_TEMP);
if (!edges)
{
rcFree(firstEdge);
return false;
}
for (int i = 0; i < nverts; i++)
firstEdge[i] = RC_MESH_NULL_IDX;
for (int i = 0; i < npolys; ++i)
{
unsigned short* t = &polys[i*vertsPerPoly*2];
for (int j = 0; j < vertsPerPoly; ++j)
{
if (t[j] == RC_MESH_NULL_IDX) break;
unsigned short v0 = t[j];
unsigned short v1 = (j+1 >= vertsPerPoly || t[j+1] == RC_MESH_NULL_IDX) ? t[0] : t[j+1];
if (v0 < v1)
{
rcEdge& edge = edges[edgeCount];
edge.vert[0] = v0;
edge.vert[1] = v1;
edge.poly[0] = (unsigned short)i;
edge.polyEdge[0] = (unsigned short)j;
edge.poly[1] = (unsigned short)i;
edge.polyEdge[1] = 0xff;
// Insert edge
nextEdge[edgeCount] = firstEdge[v0];
firstEdge[v0] = (unsigned short)edgeCount;
edgeCount++;
}
}
}
for (int i = 0; i < npolys; ++i)
{
unsigned short* t = &polys[i*vertsPerPoly*2];
for (int j = 0; j < vertsPerPoly; ++j)
{
if (t[j] == RC_MESH_NULL_IDX) break;
unsigned short v0 = t[j];
unsigned short v1 = (j+1 >= vertsPerPoly || t[j+1] == RC_MESH_NULL_IDX) ? t[0] : t[j+1];
if (v0 > v1)
{
bool found = false;
for (unsigned short e = firstEdge[v1]; e != RC_MESH_NULL_IDX; e = nextEdge[e])
{
rcEdge& edge = edges[e];
if (edge.vert[1] == v0 && edge.poly[0] == edge.poly[1])
{
edge.poly[1] = (unsigned short)i;
edge.polyEdge[1] = (unsigned short)j;
found = true;
break;
}
}
if (!found)
{
// Matching edge not found, it is an open edge, add it.
rcEdge& edge = edges[edgeCount];
edge.vert[0] = v1;
edge.vert[1] = v0;
edge.poly[0] = (unsigned short)i;
edge.polyEdge[0] = (unsigned short)j;
edge.poly[1] = (unsigned short)i;
edge.polyEdge[1] = 0xff;
// Insert edge
nextEdge[edgeCount] = firstEdge[v1];
firstEdge[v1] = (unsigned short)edgeCount;
edgeCount++;
}
}
}
}
// Mark portal edges.
for (int i = 0; i < lcset.nconts; ++i)
{
rcLayerContour& cont = lcset.conts[i];
if (cont.nverts < 3)
continue;
for (int j = 0, k = cont.nverts-1; j < cont.nverts; k=j++)
{
const unsigned char* va = &cont.verts[k*4];
const unsigned char* vb = &cont.verts[j*4];
const unsigned char dir = va[3] & 0xf;
if (dir == 0xf)
continue;
if (dir == 0 || dir == 2)
{
// Find matching vertical edge
const unsigned short x = (unsigned short)va[0];
unsigned short zmin = (unsigned short)va[2];
unsigned short zmax = (unsigned short)vb[2];
if (zmin > zmax)
rcSwap(zmin, zmax);
for (int i = 0; i < edgeCount; ++i)
{
rcEdge& e = edges[i];
// Skip connected edges.
if (e.poly[0] != e.poly[1])
continue;
const unsigned short* eva = &verts[e.vert[0]*3];
const unsigned short* evb = &verts[e.vert[1]*3];
if (eva[0] == x && evb[0] == x)
{
unsigned short ezmin = eva[2];
unsigned short ezmax = evb[2];
if (ezmin > ezmax)
rcSwap(ezmin, ezmax);
if (overlapRange(zmin,zmax, ezmin, ezmax))
{
// Reuse the other polyedge to store dir.
e.polyEdge[1] = dir;
}
}
}
}
else
{
// Find matching vertical edge
const unsigned short z = (unsigned short)va[2];
unsigned short xmin = (unsigned short)va[0];
unsigned short xmax = (unsigned short)vb[0];
if (xmin > xmax)
rcSwap(xmin, xmax);
for (int i = 0; i < edgeCount; ++i)
{
rcEdge& e = edges[i];
// Skip connected edges.
if (e.poly[0] != e.poly[1])
continue;
const unsigned short* eva = &verts[e.vert[0]*3];
const unsigned short* evb = &verts[e.vert[1]*3];
if (eva[2] == z && evb[2] == z)
{
unsigned short exmin = eva[0];
unsigned short exmax = evb[0];
if (exmin > exmax)
rcSwap(exmin, exmax);
if (overlapRange(xmin,xmax, exmin, exmax))
{
// Reuse the other polyedge to store dir.
e.polyEdge[1] = dir;
}
}
}
}
}
}
// Store adjacency
for (int i = 0; i < edgeCount; ++i)
{
const rcEdge& e = edges[i];
if (e.poly[0] != e.poly[1])
{
unsigned short* p0 = &polys[e.poly[0]*vertsPerPoly*2];
unsigned short* p1 = &polys[e.poly[1]*vertsPerPoly*2];
p0[vertsPerPoly + e.polyEdge[0]] = e.poly[1];
p1[vertsPerPoly + e.polyEdge[1]] = e.poly[0];
}
else if (e.polyEdge[1] != 0xff)
{
unsigned short* p0 = &polys[e.poly[0]*vertsPerPoly*2];
p0[vertsPerPoly + e.polyEdge[0]] = 0x8000 | (unsigned short)e.poly[1];
}
}
rcFree(firstEdge);
rcFree(edges);
return true;
}
inline int prev(int i, int n) { return i-1 >= 0 ? i-1 : n-1; }
inline int next(int i, int n) { return i+1 < n ? i+1 : 0; }
inline int area2(const unsigned char* a, const unsigned char* b, const unsigned char* c)
{
return ((int)b[0] - (int)a[0]) * ((int)c[2] - (int)a[2]) - ((int)c[0] - (int)a[0]) * ((int)b[2] - (int)a[2]);
}
// Exclusive or: true iff exactly one argument is true.
// The arguments are negated to ensure that they are 0/1
// values. Then the bitwise Xor operator may apply.
// (This idea is due to Michael Baldwin.)
inline bool xorb(bool x, bool y)
{
return !x ^ !y;
}
// Returns true iff c is strictly to the left of the directed
// line through a to b.
inline bool left(const unsigned char* a, const unsigned char* b, const unsigned char* c)
{
return area2(a, b, c) < 0;
}
inline bool leftOn(const unsigned char* a, const unsigned char* b, const unsigned char* c)
{
return area2(a, b, c) <= 0;
}
inline bool collinear(const unsigned char* a, const unsigned char* b, const unsigned char* c)
{
return area2(a, b, c) == 0;
}
// Returns true iff ab properly intersects cd: they share
// a point interior to both segments. The properness of the
// intersection is ensured by using strict leftness.
static bool intersectProp(const unsigned char* a, const unsigned char* b,
const unsigned char* c, const unsigned char* d)
{
// Eliminate improper cases.
if (collinear(a,b,c) || collinear(a,b,d) ||
collinear(c,d,a) || collinear(c,d,b))
return false;
return xorb(left(a,b,c), left(a,b,d)) && xorb(left(c,d,a), left(c,d,b));
}
// Returns T iff (a,b,c) are collinear and point c lies
// on the closed segement ab.
static bool between(const unsigned char* a, const unsigned char* b, const unsigned char* c)
{
if (!collinear(a, b, c))
return false;
// If ab not vertical, check betweenness on x; else on y.
if (a[0] != b[0])
return ((a[0] <= c[0]) && (c[0] <= b[0])) || ((a[0] >= c[0]) && (c[0] >= b[0]));
else
return ((a[2] <= c[2]) && (c[2] <= b[2])) || ((a[2] >= c[2]) && (c[2] >= b[2]));
}
// Returns true iff segments ab and cd intersect, properly or improperly.
static bool intersect(const unsigned char* a, const unsigned char* b,
const unsigned char* c, const unsigned char* d)
{
if (intersectProp(a, b, c, d))
return true;
else if (between(a, b, c) || between(a, b, d) ||
between(c, d, a) || between(c, d, b))
return true;
else
return false;
}
static bool vequal(const unsigned char* a, const unsigned char* b)
{
return a[0] == b[0] && a[2] == b[2];
}
// Returns T iff (v_i, v_j) is a proper internal *or* external
// diagonal of P, *ignoring edges incident to v_i and v_j*.
static bool diagonalie(int i, int j, int n, const unsigned char* verts, const unsigned short* indices)
{
const unsigned char* d0 = &verts[(indices[i] & 0x7fff) * 4];
const unsigned char* d1 = &verts[(indices[j] & 0x7fff) * 4];
// For each edge (k,k+1) of P
for (int k = 0; k < n; k++)
{
int k1 = next(k, n);
// Skip edges incident to i or j
if (!((k == i) || (k1 == i) || (k == j) || (k1 == j)))
{
const unsigned char* p0 = &verts[(indices[k] & 0x7fff) * 4];
const unsigned char* p1 = &verts[(indices[k1] & 0x7fff) * 4];
if (vequal(d0, p0) || vequal(d1, p0) || vequal(d0, p1) || vequal(d1, p1))
continue;
if (intersect(d0, d1, p0, p1))
return false;
}
}
return true;
}
// Returns true iff the diagonal (i,j) is strictly internal to the
// polygon P in the neighborhood of the i endpoint.
static bool inCone(int i, int j, int n, const unsigned char* verts, const unsigned short* indices)
{
const unsigned char* pi = &verts[(indices[i] & 0x7fff) * 4];
const unsigned char* pj = &verts[(indices[j] & 0x7fff) * 4];
const unsigned char* pi1 = &verts[(indices[next(i, n)] & 0x7fff) * 4];
const unsigned char* pin1 = &verts[(indices[prev(i, n)] & 0x7fff) * 4];
// If P[i] is a convex vertex [ i+1 left or on (i-1,i) ].
if (leftOn(pin1, pi, pi1))
return left(pi, pj, pin1) && left(pj, pi, pi1);
// Assume (i-1,i,i+1) not collinear.
// else P[i] is reflex.
return !(leftOn(pi, pj, pi1) && leftOn(pj, pi, pin1));
}
// Returns T iff (v_i, v_j) is a proper internal
// diagonal of P.
static bool diagonal(int i, int j, int n, const unsigned char* verts, const unsigned short* indices)
{
return inCone(i, j, n, verts, indices) && diagonalie(i, j, n, verts, indices);
}
static int triangulate(int n, const unsigned char* verts, unsigned short* indices, unsigned short* tris)
{
int ntris = 0;
unsigned short* dst = tris;
// The last bit of the index is used to indicate if the vertex can be removed.
for (int i = 0; i < n; i++)
{
int i1 = next(i, n);
int i2 = next(i1, n);
if (diagonal(i, i2, n, verts, indices))
indices[i1] |= 0x8000;
}
while (n > 3)
{
int minLen = -1;
int mini = -1;
for (int i = 0; i < n; i++)
{
int i1 = next(i, n);
if (indices[i1] & 0x8000)
{
const unsigned char* p0 = &verts[(indices[i] & 0x7fff) * 4];
const unsigned char* p2 = &verts[(indices[next(i1, n)] & 0x7fff) * 4];
const int dx = (int)p2[0] - (int)p0[0];
const int dz = (int)p2[2] - (int)p0[2];
const int len = dx*dx + dz*dz;
if (minLen < 0 || len < minLen)
{
minLen = len;
mini = i;
}
}
}
if (mini == -1)
{
// Should not happen.
/* printf("mini == -1 ntris=%d n=%d\n", ntris, n);
for (int i = 0; i < n; i++)
{
printf("%d ", indices[i] & 0x0fffffff);
}
printf("\n");*/
return -ntris;
}
int i = mini;
int i1 = next(i, n);
int i2 = next(i1, n);
*dst++ = indices[i] & 0x7fff;
*dst++ = indices[i1] & 0x7fff;
*dst++ = indices[i2] & 0x7fff;
ntris++;
// Removes P[i1] by copying P[i+1]...P[n-1] left one index.
n--;
for (int k = i1; k < n; k++)
indices[k] = indices[k+1];
if (i1 >= n) i1 = 0;
i = prev(i1,n);
// Update diagonal flags.
if (diagonal(prev(i, n), i1, n, verts, indices))
indices[i] |= 0x8000;
else
indices[i] &= 0x7fff;
if (diagonal(i, next(i1, n), n, verts, indices))
indices[i1] |= 0x8000;
else
indices[i1] &= 0x7fff;
}
// Append the remaining triangle.
*dst++ = indices[0] & 0x7fff;
*dst++ = indices[1] & 0x7fff;
*dst++ = indices[2] & 0x7fff;
ntris++;
return ntris;
}
static const int MAX_VERTS_PER_POLY = 6;
static const int MAX_REM_EDGES = 48;
static int countPolyVerts(const unsigned short* p, const int nvp)
{
for (int i = 0; i < nvp; ++i)
if (p[i] == RC_MESH_NULL_IDX)
return i;
return nvp;
}
inline bool uleft(const unsigned short* a, const unsigned short* b, const unsigned short* c)
{
return ((int)b[0] - (int)a[0]) * ((int)c[2] - (int)a[2]) -
((int)c[0] - (int)a[0]) * ((int)b[2] - (int)a[2]) < 0;
}
static int getPolyMergeValue(unsigned short* pa, unsigned short* pb,
const unsigned short* verts, int& ea, int& eb,
const int nvp)
{
const int na = countPolyVerts(pa, nvp);
const int nb = countPolyVerts(pb, nvp);
// If the merged polygon would be too big, do not merge.
if (na+nb-2 > nvp)
return -1;
// Check if the polygons share an edge.
ea = -1;
eb = -1;
for (int i = 0; i < na; ++i)
{
unsigned short va0 = pa[i];
unsigned short va1 = pa[(i+1) % na];
if (va0 > va1)
rcSwap(va0, va1);
for (int j = 0; j < nb; ++j)
{
unsigned short vb0 = pb[j];
unsigned short vb1 = pb[(j+1) % nb];
if (vb0 > vb1)
rcSwap(vb0, vb1);
if (va0 == vb0 && va1 == vb1)
{
ea = i;
eb = j;
break;
}
}
}
// No common edge, cannot merge.
if (ea == -1 || eb == -1)
return -1;
// Check to see if the merged polygon would be convex.
unsigned short va, vb, vc;
va = pa[(ea+na-1) % na];
vb = pa[ea];
vc = pb[(eb+2) % nb];
if (!uleft(&verts[va*3], &verts[vb*3], &verts[vc*3]))
return -1;
va = pb[(eb+nb-1) % nb];
vb = pb[eb];
vc = pa[(ea+2) % na];
if (!uleft(&verts[va*3], &verts[vb*3], &verts[vc*3]))
return -1;
va = pa[ea];
vb = pa[(ea+1)%na];
int dx = (int)verts[va*3+0] - (int)verts[vb*3+0];
int dy = (int)verts[va*3+2] - (int)verts[vb*3+2];
return dx*dx + dy*dy;
}
static void mergePolys(unsigned short* pa, unsigned short* pb, int ea, int eb, const int nvp)
{
unsigned short tmp[MAX_VERTS_PER_POLY*2];
const int na = countPolyVerts(pa, nvp);
const int nb = countPolyVerts(pb, nvp);
// Merge polygons.
memset(tmp, 0xff, sizeof(unsigned short)*nvp);
int n = 0;
// Add pa
for (int i = 0; i < na-1; ++i)
tmp[n++] = pa[(ea+1+i) % na];
// Add pb
for (int i = 0; i < nb-1; ++i)
tmp[n++] = pb[(eb+1+i) % nb];
memcpy(pa, tmp, sizeof(unsigned short)*nvp);
}
static void pushFront(unsigned short v, unsigned short* arr, int& an)
{
an++;
for (int i = an-1; i > 0; --i)
arr[i] = arr[i-1];
arr[0] = v;
}
static void pushBack(unsigned short v, unsigned short* arr, int& an)
{
arr[an] = v;
an++;
}
static bool canRemoveVertex(rcContext* ctx, rcLayerPolyMesh& mesh, const unsigned short rem)
{
const int nvp = mesh.nvp;
// Count number of polygons to remove.
int numRemovedVerts = 0;
int numTouchedVerts = 0;
int numRemainingEdges = 0;
for (int i = 0; i < mesh.npolys; ++i)
{
unsigned short* p = &mesh.polys[i*nvp*2];
const int nv = countPolyVerts(p, nvp);
int numRemoved = 0;
int numVerts = 0;
for (int j = 0; j < nv; ++j)
{
if (p[j] == rem)
{
numTouchedVerts++;
numRemoved++;
}
numVerts++;
}
if (numRemoved)
{
numRemovedVerts += numRemoved;
numRemainingEdges += numVerts-(numRemoved+1);
}
}
// There would be too few edges remaining to create a polygon.
// This can happen for example when a tip of a triangle is marked
// as deletion, but there are no other polys that share the vertex.
// In this case, the vertex should not be removed.
if (numRemainingEdges <= 2)
return false;
// Check that there is enough memory for the test.
const int maxEdges = numTouchedVerts*2;
if (maxEdges > MAX_REM_EDGES)
return false;
// Find edges which share the removed vertex.
unsigned short edges[MAX_REM_EDGES];
int nedges = 0;
for (int i = 0; i < mesh.npolys; ++i)
{
unsigned short* p = &mesh.polys[i*nvp*2];
const int nv = countPolyVerts(p, nvp);
// Collect edges which touches the removed vertex.
for (int j = 0, k = nv-1; j < nv; k = j++)
{
if (p[j] == rem || p[k] == rem)
{
// Arrange edge so that a=rem.
int a = p[j], b = p[k];
if (b == rem)
rcSwap(a,b);
// Check if the edge exists
bool exists = false;
for (int k = 0; k < nedges; ++k)
{
unsigned short* e = &edges[k*3];
if (e[1] == b)
{
// Exists, increment vertex share count.
e[2]++;
exists = true;
}
}
// Add new edge.
if (!exists)
{
unsigned short* e = &edges[nedges*3];
e[0] = a;
e[1] = b;
e[2] = 1;
nedges++;
}
}
}
}
// There should be no more than 2 open edges.
// This catches the case that two non-adjacent polygons
// share the removed vertex. In that case, do not remove the vertex.
int numOpenEdges = 0;
for (int i = 0; i < nedges; ++i)
{
if (edges[i*3+2] < 2)
numOpenEdges++;
}
if (numOpenEdges > 2)
return false;
return true;
}
static bool removeVertex(rcContext* ctx, rcLayerPolyMesh& mesh, const unsigned short rem, const int maxTris)
{
const int nvp = mesh.nvp;
// Count number of polygons to remove.
int numRemovedVerts = 0;
for (int i = 0; i < mesh.npolys; ++i)
{
unsigned short* p = &mesh.polys[i*nvp*2];
const int nv = countPolyVerts(p, nvp);
for (int j = 0; j < nv; ++j)
{
if (p[j] == rem)
numRemovedVerts++;
}
}
int nedges = 0;
unsigned short edges[MAX_REM_EDGES*3];
int nhole = 0;
unsigned short hole[MAX_REM_EDGES];
int nharea = 0;
unsigned short harea[MAX_REM_EDGES];
for (int i = 0; i < mesh.npolys; ++i)
{
unsigned short* p = &mesh.polys[i*nvp*2];
const int nv = countPolyVerts(p, nvp);
bool hasRem = false;
for (int j = 0; j < nv; ++j)
if (p[j] == rem) hasRem = true;
if (hasRem)
{
// Collect edges which does not touch the removed vertex.
for (int j = 0, k = nv-1; j < nv; k = j++)
{
if (p[j] != rem && p[k] != rem)
{
if (nedges >= MAX_REM_EDGES)
return false;
unsigned short* e = &edges[nedges*3];
e[0] = p[k];
e[1] = p[j];
e[2] = mesh.areas[i];
nedges++;
}
}
// Remove the polygon.
unsigned short* p2 = &mesh.polys[(mesh.npolys-1)*nvp*2];
memcpy(p,p2,sizeof(unsigned short)*nvp);
memset(p+nvp,0xff,sizeof(unsigned short)*nvp);
mesh.areas[i] = mesh.areas[mesh.npolys-1];
mesh.npolys--;
--i;
}
}
// Remove vertex.
for (int i = (int)rem; i < mesh.nverts; ++i)
{
mesh.verts[i*3+0] = mesh.verts[(i+1)*3+0];
mesh.verts[i*3+1] = mesh.verts[(i+1)*3+1];
mesh.verts[i*3+2] = mesh.verts[(i+1)*3+2];
}
mesh.nverts--;
// Adjust indices to match the removed vertex layout.
for (int i = 0; i < mesh.npolys; ++i)
{
unsigned short* p = &mesh.polys[i*nvp*2];
const int nv = countPolyVerts(p, nvp);
for (int j = 0; j < nv; ++j)
if (p[j] > rem) p[j]--;
}
for (int i = 0; i < nedges; ++i)
{
if (edges[i*3+0] > rem) edges[i*3+0]--;
if (edges[i*3+1] > rem) edges[i*3+1]--;
}
if (nedges == 0)
return true;
// Start with one vertex, keep appending connected
// segments to the start and end of the hole.
pushBack(edges[0], hole, nhole);
pushBack(edges[2], harea, nharea);
while (nedges)
{
bool match = false;
for (int i = 0; i < nedges; ++i)
{
const unsigned short ea = edges[i*3+0];
const unsigned short eb = edges[i*3+1];
const unsigned short a = edges[i*3+2];
bool add = false;
if (hole[0] == eb)
{
// The segment matches the beginning of the hole boundary.
if (nhole >= MAX_REM_EDGES)
return false;
pushFront(ea, hole, nhole);
pushFront(a, harea, nharea);
add = true;
}
else if (hole[nhole-1] == ea)
{
// The segment matches the end of the hole boundary.
if (nhole >= MAX_REM_EDGES)
return false;
pushBack(eb, hole, nhole);
pushBack(a, harea, nharea);
add = true;
}
if (add)
{
// The edge segment was added, remove it.
edges[i*3+0] = edges[(nedges-1)*3+0];
edges[i*3+1] = edges[(nedges-1)*3+1];
edges[i*3+2] = edges[(nedges-1)*3+2];
--nedges;
match = true;
--i;
}
}
if (!match)
break;
}
unsigned short tris[MAX_REM_EDGES*3];
unsigned char tverts[MAX_REM_EDGES*3];
unsigned short tpoly[MAX_REM_EDGES*3];
// Generate temp vertex array for triangulation.
for (int i = 0; i < nhole; ++i)
{
const unsigned short pi = hole[i];
tverts[i*4+0] = (unsigned char)mesh.verts[pi*3+0];
tverts[i*4+1] = (unsigned char)mesh.verts[pi*3+1];
tverts[i*4+2] = (unsigned char)mesh.verts[pi*3+2];
tverts[i*4+3] = 0;
tpoly[i] = (unsigned short)i;
}
// Triangulate the hole.
int ntris = triangulate(nhole, tverts, tpoly, tris);
if (ntris < 0)
{
ntris = -ntris;
ctx->log(RC_LOG_WARNING, "removeVertex: triangulate() returned bad results.");
}
if (ntris > MAX_REM_EDGES)
return false;
unsigned short polys[MAX_REM_EDGES*MAX_VERTS_PER_POLY];
unsigned char pareas[MAX_REM_EDGES];
// Build initial polygons.
int npolys = 0;
memset(polys, 0xff, ntris*nvp*sizeof(unsigned short));
for (int j = 0; j < ntris; ++j)
{
unsigned short* t = &tris[j*3];
if (t[0] != t[1] && t[0] != t[2] && t[1] != t[2])
{
polys[npolys*nvp+0] = hole[t[0]];
polys[npolys*nvp+1] = hole[t[1]];
polys[npolys*nvp+2] = hole[t[2]];
pareas[npolys] = (unsigned char)harea[t[0]];
npolys++;
}
}
if (!npolys)
return true;
// Merge polygons.
if (nvp > 3)
{
for (;;)
{
// Find best polygons to merge.
int bestMergeVal = 0;
int bestPa = 0, bestPb = 0, bestEa = 0, bestEb = 0;
for (int j = 0; j < npolys-1; ++j)
{
unsigned short* pj = &polys[j*nvp];
for (int k = j+1; k < npolys; ++k)
{
unsigned short* pk = &polys[k*nvp];
int ea, eb;
int v = getPolyMergeValue(pj, pk, mesh.verts, ea, eb, nvp);
if (v > bestMergeVal)
{
bestMergeVal = v;
bestPa = j;
bestPb = k;
bestEa = ea;
bestEb = eb;
}
}
}
if (bestMergeVal > 0)
{
// Found best, merge.
unsigned short* pa = &polys[bestPa*nvp];
unsigned short* pb = &polys[bestPb*nvp];
mergePolys(pa, pb, bestEa, bestEb, nvp);
memcpy(pb, &polys[(npolys-1)*nvp], sizeof(unsigned short)*nvp);
pareas[bestPb] = pareas[npolys-1];
npolys--;
}
else
{
// Could not merge any polygons, stop.
break;
}
}
}
// Store polygons.
for (int i = 0; i < npolys; ++i)
{
if (mesh.npolys >= maxTris) break;
unsigned short* p = &mesh.polys[mesh.npolys*nvp*2];
memset(p,0xff,sizeof(unsigned short)*nvp*2);
for (int j = 0; j < nvp; ++j)
p[j] = polys[i*nvp+j];
mesh.areas[mesh.npolys] = pareas[i];
mesh.npolys++;
if (mesh.npolys > maxTris)
{
ctx->log(RC_LOG_ERROR, "removeVertex: Too many polygons %d (max:%d).", mesh.npolys, maxTris);
return false;
}
}
return true;
}
bool rcBuildLayerPolyMesh(rcContext* ctx,
rcLayerContourSet& lcset,
const int maxVertsPerPoly,
rcLayerPolyMesh& mesh)
{
rcAssert(ctx);
const int nvp = rcMin(maxVertsPerPoly, MAX_VERTS_PER_POLY);
// ctx->startTimer(RC_TIMER_BUILD_POLYMESH);
rcVcopy(mesh.bmin, lcset.bmin);
rcVcopy(mesh.bmax, lcset.bmax);
mesh.cs = lcset.cs;
mesh.ch = lcset.ch;
int maxVertices = 0;
int maxTris = 0;
int maxVertsPerCont = 0;
for (int i = 0; i < lcset.nconts; ++i)
{
// Skip null contours.
if (lcset.conts[i].nverts < 3) continue;
maxVertices += lcset.conts[i].nverts;
maxTris += lcset.conts[i].nverts - 2;
maxVertsPerCont = rcMax(maxVertsPerCont, lcset.conts[i].nverts);
}
if (maxVertices >= 0xfffe)
{
ctx->log(RC_LOG_ERROR, "rcBuildLayerPolyMesh: Too many vertices %d.", maxVertices);
return false;
}
rcScopedDelete<unsigned char> vflags = (unsigned char*)rcAlloc(sizeof(unsigned char)*maxVertices, RC_ALLOC_TEMP);
if (!vflags)
{
ctx->log(RC_LOG_ERROR, "rcBuildLayerPolyMesh: Out of memory 'vflags' (%d).", maxVertices);
return false;
}
memset(vflags, 0, maxVertices);
mesh.verts = (unsigned short*)rcAlloc(sizeof(unsigned short)*maxVertices*3, RC_ALLOC_PERM);
if (!mesh.verts)
{
ctx->log(RC_LOG_ERROR, "rcBuildLayerPolyMesh: Out of memory 'mesh.verts' (%d).", maxVertices);
return false;
}
mesh.polys = (unsigned short*)rcAlloc(sizeof(unsigned short)*maxTris*nvp*2*2, RC_ALLOC_PERM);
if (!mesh.polys)
{
ctx->log(RC_LOG_ERROR, "rcBuildLayerPolyMesh: Out of memory 'mesh.polys' (%d).", maxTris*nvp*2);
return false;
}
mesh.areas = (unsigned char*)rcAlloc(sizeof(unsigned char)*maxTris, RC_ALLOC_PERM);
if (!mesh.areas)
{
ctx->log(RC_LOG_ERROR, "rcBuildLayerPolyMesh: Out of memory 'mesh.areas' (%d).", maxTris);
return false;
}
mesh.flags = (unsigned short*)rcAlloc(sizeof(unsigned short)*mesh.npolys, RC_ALLOC_PERM);
if (!mesh.flags)
{
ctx->log(RC_LOG_ERROR, "rcBuildLayerPolyMesh: Out of memory 'mesh.flags' (%d).", mesh.npolys);
return false;
}
// Just allocate and clean the mesh flags array. The user is resposible for filling it.
memset(mesh.flags, 0, sizeof(unsigned short) * mesh.npolys);
mesh.nverts = 0;
mesh.npolys = 0;
mesh.nvp = nvp;
mesh.maxpolys = maxTris;
memset(mesh.verts, 0, sizeof(unsigned short)*maxVertices*3);
memset(mesh.polys, 0xff, sizeof(unsigned short)*maxTris*nvp*2);
memset(mesh.areas, 0, sizeof(unsigned char)*maxTris);
unsigned short firstVert[VERTEX_BUCKET_COUNT2];
for (int i = 0; i < VERTEX_BUCKET_COUNT2; ++i)
firstVert[i] = RC_MESH_NULL_IDX;
rcScopedDelete<unsigned short> nextVert = (unsigned short*)rcAlloc(sizeof(unsigned short)*maxVertices, RC_ALLOC_TEMP);
if (!nextVert)
{
ctx->log(RC_LOG_ERROR, "rcBuildLayerPolyMesh: Out of memory 'nextVert' (%d).", maxVertices);
return false;
}
memset(nextVert, 0, sizeof(unsigned short)*maxVertices);
rcScopedDelete<unsigned short> indices = (unsigned short*)rcAlloc(sizeof(unsigned short)*maxVertsPerCont, RC_ALLOC_TEMP);
if (!indices)
{
ctx->log(RC_LOG_ERROR, "rcBuildLayerPolyMesh: Out of memory 'indices' (%d).", maxVertsPerCont);
return false;
}
rcScopedDelete<unsigned short> tris = (unsigned short*)rcAlloc(sizeof(unsigned short)*maxVertsPerCont*3, RC_ALLOC_TEMP);
if (!tris)
{
ctx->log(RC_LOG_ERROR, "rcBuildLayerPolyMesh: Out of memory 'tris' (%d).", maxVertsPerCont*3);
return false;
}
rcScopedDelete<unsigned short> polys = (unsigned short*)rcAlloc(sizeof(unsigned short)*maxVertsPerCont*nvp, RC_ALLOC_TEMP);
if (!polys)
{
ctx->log(RC_LOG_ERROR, "rcBuildLayerPolyMesh: Out of memory 'polys' (%d).", maxVertsPerCont*nvp);
return false;
}
for (int i = 0; i < lcset.nconts; ++i)
{
rcLayerContour& cont = lcset.conts[i];
// Skip null contours.
if (cont.nverts < 3)
continue;
// Triangulate contour
for (int j = 0; j < cont.nverts; ++j)
indices[j] = (unsigned short)j;
int ntris = triangulate(cont.nverts, cont.verts, &indices[0], &tris[0]);
if (ntris <= 0)
{
ctx->log(RC_LOG_WARNING, "rcBuildLayerPolyMesh: Bad triangulation Contour %d.", i);
ntris = -ntris;
}
// Add and merge vertices.
for (int j = 0; j < cont.nverts; ++j)
{
const unsigned char* v = &cont.verts[j*4];
indices[j] = addVertex((unsigned short)v[0], (unsigned short)v[1], (unsigned short)v[2],
mesh.verts, firstVert, nextVert, mesh.nverts);
if (v[3] & 0x80)
{
// This vertex should be removed.
vflags[indices[j]] = 1;
}
}
// Build initial polygons.
int npolys = 0;
memset(polys, 0xff, sizeof(unsigned short) * maxVertsPerCont * nvp);
for (int j = 0; j < ntris; ++j)
{
const unsigned short* t = &tris[j*3];
if (t[0] != t[1] && t[0] != t[2] && t[1] != t[2])
{
polys[npolys*nvp+0] = indices[t[0]];
polys[npolys*nvp+1] = indices[t[1]];
polys[npolys*nvp+2] = indices[t[2]];
npolys++;
}
}
if (!npolys)
continue;
// Merge polygons.
if (nvp > 3)
{
for(;;)
{
// Find best polygons to merge.
int bestMergeVal = 0;
int bestPa = 0, bestPb = 0, bestEa = 0, bestEb = 0;
for (int j = 0; j < npolys-1; ++j)
{
unsigned short* pj = &polys[j*nvp];
for (int k = j+1; k < npolys; ++k)
{
unsigned short* pk = &polys[k*nvp];
int ea, eb;
int v = getPolyMergeValue(pj, pk, mesh.verts, ea, eb, nvp);
if (v > bestMergeVal)
{
bestMergeVal = v;
bestPa = j;
bestPb = k;
bestEa = ea;
bestEb = eb;
}
}
}
if (bestMergeVal > 0)
{
// Found best, merge.
unsigned short* pa = &polys[bestPa*nvp];
unsigned short* pb = &polys[bestPb*nvp];
mergePolys(pa, pb, bestEa, bestEb, nvp);
memcpy(pb, &polys[(npolys-1)*nvp], sizeof(unsigned short)*nvp);
npolys--;
}
else
{
// Could not merge any polygons, stop.
break;
}
}
}
// Store polygons.
for (int j = 0; j < npolys; ++j)
{
unsigned short* p = &mesh.polys[mesh.npolys*nvp*2];
unsigned short* q = &polys[j*nvp];
for (int k = 0; k < nvp; ++k)
p[k] = q[k];
mesh.areas[mesh.npolys] = cont.area;
mesh.npolys++;
if (mesh.npolys > maxTris)
{
ctx->log(RC_LOG_ERROR, "rcBuildLayerPolyMesh: Too many polygons %d (max:%d).", mesh.npolys, maxTris);
return false;
}
}
}
// Remove edge vertices.
for (int i = 0; i < mesh.nverts; ++i)
{
if (vflags[i])
{
if (!canRemoveVertex(ctx, mesh, (unsigned short)i))
continue;
if (!removeVertex(ctx, mesh, (unsigned short)i, maxTris))
{
// Failed to remove vertex
ctx->log(RC_LOG_ERROR, "rcBuildPolyMesh: Failed to remove edge vertex %d.", i);
return false;
}
// Remove vertex
// Note: mesh.nverts is already decremented inside removeVertex()!
for (int j = i; j < mesh.nverts; ++j)
vflags[j] = vflags[j+1];
--i;
}
}
// Calculate adjacency.
if (!buildMeshAdjacency(mesh.polys, mesh.npolys, mesh.verts, mesh.nverts, nvp, lcset))
{
ctx->log(RC_LOG_ERROR, "rcBuildLayerPolyMesh: Adjacency failed.");
return false;
}
if (mesh.nverts > 0xffff)
{
ctx->log(RC_LOG_ERROR, "rcBuildLayerPolyMesh: The resulting mesh has too many vertices %d (max %d). Data can be corrupted.", mesh.nverts, 0xffff);
}
if (mesh.npolys > 0xffff)
{
ctx->log(RC_LOG_ERROR, "rcBuildLayerPolyMesh: The resulting mesh has too many polygons %d (max %d). Data can be corrupted.", mesh.npolys, 0xffff);
}
// ctx->stopTimer(RC_TIMER_BUILD_POLYMESH);
return true;
}