Merge pull request #151 from Janiels/fix-detail-sampling

Use flood fill for potentially overlapping polys
This commit is contained in:
Jakob Botsch Nielsen 2016-01-14 16:48:13 +01:00
commit f002387afc
5 changed files with 214 additions and 169 deletions

View File

@ -513,6 +513,14 @@ void rcFreePolyMeshDetail(rcPolyMeshDetail* dmesh);
/// @see rcCompactSpan::reg
static const unsigned short RC_BORDER_REG = 0x8000;
/// Polygon touches multiple regions.
/// If a polygon has this region ID it was merged with or created
/// from polygons of different regions during the polymesh
/// build step that removes redundant border vertices.
/// (Used during the polymesh and detail polymesh build processes)
/// @see rcPolyMesh::regs
static const unsigned short RC_MULTIPLE_REGS = 0;
/// Border vertex flag.
/// If a region ID has this bit set, then the associated element lies on
/// a tile border. If a contour vertex's region ID has this bit set, the
@ -1059,7 +1067,7 @@ inline int rcGetCon(const rcCompactSpan& s, int dir)
/// in the direction.
inline int rcGetDirOffsetX(int dir)
{
const int offset[4] = { -1, 0, 1, 0, };
static const int offset[4] = { -1, 0, 1, 0, };
return offset[dir&0x03];
}
@ -1069,10 +1077,20 @@ inline int rcGetDirOffsetX(int dir)
/// in the direction.
inline int rcGetDirOffsetY(int dir)
{
const int offset[4] = { 0, 1, 0, -1 };
static const int offset[4] = { 0, 1, 0, -1 };
return offset[dir&0x03];
}
/// Gets the direction for the specified offset. One of x and y should be 0.
/// @param[in] x The x offset. [Limits: -1 <= value <= 1]
/// @param[in] y The y offset. [Limits: -1 <= value <= 1]
/// @return The direction that represents the offset.
inline int rcGetDirForOffset(int x, int y)
{
static const int dirs[5] = { 3, 0, -1, 2, 1 };
return dirs[((y+1)<<1)+x];
}
/// @}
/// @name Layer, Contour, Polymesh, and Detail Mesh Functions
/// @see rcHeightfieldLayer, rcContourSet, rcPolyMesh, rcPolyMeshDetail

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@ -64,40 +64,54 @@ class rcIntArray
int m_size, m_cap;
inline rcIntArray(const rcIntArray&);
inline rcIntArray& operator=(const rcIntArray&);
void doResize(int n);
public:
/// Constructs an instance with an initial array size of zero.
inline rcIntArray() : m_data(0), m_size(0), m_cap(0) {}
rcIntArray() : m_data(0), m_size(0), m_cap(0) {}
/// Constructs an instance initialized to the specified size.
/// @param[in] n The initial size of the integer array.
inline rcIntArray(int n) : m_data(0), m_size(0), m_cap(0) { resize(n); }
inline ~rcIntArray() { rcFree(m_data); }
rcIntArray(int n) : m_data(0), m_size(0), m_cap(0) { resize(n); }
~rcIntArray() { rcFree(m_data); }
/// Specifies the new size of the integer array.
/// @param[in] n The new size of the integer array.
void resize(int n);
void resize(int n)
{
if (n > m_cap)
doResize(n);
m_size = n;
}
/// Push the specified integer onto the end of the array and increases the size by one.
/// @param[in] item The new value.
inline void push(int item) { resize(m_size+1); m_data[m_size-1] = item; }
void push(int item) { resize(m_size+1); m_data[m_size-1] = item; }
/// Returns the value at the end of the array and reduces the size by one.
/// @return The value at the end of the array.
inline int pop() { if (m_size > 0) m_size--; return m_data[m_size]; }
int pop()
{
if (m_size > 0)
m_size--;
return m_data[m_size];
}
/// The value at the specified array index.
/// @warning Does not provide overflow protection.
/// @param[in] i The index of the value.
inline const int& operator[](int i) const { return m_data[i]; }
const int& operator[](int i) const { return m_data[i]; }
/// The value at the specified array index.
/// @warning Does not provide overflow protection.
/// @param[in] i The index of the value.
inline int& operator[](int i) { return m_data[i]; }
int& operator[](int i) { return m_data[i]; }
/// The current size of the integer array.
inline int size() const { return m_size; }
int size() const { return m_size; }
};
/// A simple helper class used to delete an array when it goes out of scope.

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@ -72,17 +72,13 @@ void rcFree(void* ptr)
/// Using this method ensures the array is at least large enough to hold
/// the specified number of elements. This can improve performance by
/// avoiding auto-resizing during use.
void rcIntArray::resize(int n)
void rcIntArray::doResize(int n)
{
if (n > m_cap)
{
if (!m_cap) m_cap = n;
while (m_cap < n) m_cap *= 2;
int* newData = (int*)rcAlloc(m_cap*sizeof(int), RC_ALLOC_TEMP);
if (m_size && newData) memcpy(newData, m_data, m_size*sizeof(int));
rcFree(m_data);
m_data = newData;
}
m_size = n;
}

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@ -528,7 +528,7 @@ static int getPolyMergeValue(unsigned short* pa, unsigned short* pb,
return dx*dx + dy*dy;
}
static void mergePolys(unsigned short* pa, unsigned short* pb, int ea, int eb,
static void mergePolyVerts(unsigned short* pa, unsigned short* pb, int ea, int eb,
unsigned short* tmp, const int nvp)
{
const int na = countPolyVerts(pa, nvp);
@ -895,7 +895,14 @@ static bool removeVertex(rcContext* ctx, rcPolyMesh& mesh, const unsigned short
polys[npolys*nvp+0] = (unsigned short)hole[t[0]];
polys[npolys*nvp+1] = (unsigned short)hole[t[1]];
polys[npolys*nvp+2] = (unsigned short)hole[t[2]];
// If this polygon covers multiple region types then
// mark it as such
if (hreg[t[0]] != hreg[t[1]] || hreg[t[1]] != hreg[t[2]])
pregs[npolys] = RC_MULTIPLE_REGS;
else
pregs[npolys] = (unsigned short)hreg[t[0]];
pareas[npolys] = (unsigned char)harea[t[0]];
npolys++;
}
@ -936,7 +943,10 @@ static bool removeVertex(rcContext* ctx, rcPolyMesh& mesh, const unsigned short
// Found best, merge.
unsigned short* pa = &polys[bestPa*nvp];
unsigned short* pb = &polys[bestPb*nvp];
mergePolys(pa, pb, bestEa, bestEb, tmpPoly, nvp);
mergePolyVerts(pa, pb, bestEa, bestEb, tmpPoly, nvp);
if (pregs[bestPa] != pregs[bestPb])
pregs[bestPa] = RC_MULTIPLE_REGS;
unsigned short* last = &polys[(npolys-1)*nvp];
if (pb != last)
memcpy(pb, last, sizeof(unsigned short)*nvp);
@ -1182,7 +1192,7 @@ bool rcBuildPolyMesh(rcContext* ctx, rcContourSet& cset, const int nvp, rcPolyMe
// Found best, merge.
unsigned short* pa = &polys[bestPa*nvp];
unsigned short* pb = &polys[bestPb*nvp];
mergePolys(pa, pb, bestEa, bestEb, tmpPoly, nvp);
mergePolyVerts(pa, pb, bestEa, bestEb, tmpPoly, nvp);
unsigned short* lastPoly = &polys[(npolys-1)*nvp];
if (pb != lastPoly)
memcpy(pb, lastPoly, sizeof(unsigned short)*nvp);

View File

@ -834,33 +834,25 @@ static bool buildPolyDetail(rcContext* ctx, const float* in, const int nin,
return true;
}
static void getHeightDataSeedsFromVertices(const rcCompactHeightfield& chf,
static void seedArrayWithPolyCenter(rcContext* ctx, const rcCompactHeightfield& chf,
const unsigned short* poly, const int npoly,
const unsigned short* verts, const int bs,
rcHeightPatch& hp, rcIntArray& stack)
rcHeightPatch& hp, rcIntArray& array)
{
// Floodfill the heightfield to get 2D height data,
// starting at vertex locations as seeds.
// Note: Reads to the compact heightfield are offset by border size (bs)
// since border size offset is already removed from the polymesh vertices.
memset(hp.data, 0, sizeof(unsigned short)*hp.width*hp.height);
stack.resize(0);
static const int offset[9*2] =
{
0,0, -1,-1, 0,-1, 1,-1, 1,0, 1,1, 0,1, -1,1, -1,0,
};
// Use poly vertices as seed points for the flood fill.
for (int j = 0; j < npoly; ++j)
{
int cx = 0, cz = 0, ci =-1;
// Find cell closest to a poly vertex
int startCellX = 0, startCellY = 0, startSpanIndex = -1;
int dmin = RC_UNSET_HEIGHT;
for (int k = 0; k < 9; ++k)
for (int j = 0; j < npoly && dmin > 0; ++j)
{
for (int k = 0; k < 9 && dmin > 0; ++k)
{
const int ax = (int)verts[poly[j]*3+0] + offset[k*2+0];
const int ay = (int)verts[poly[j]*3+1];
@ -870,123 +862,139 @@ static void getHeightDataSeedsFromVertices(const rcCompactHeightfield& chf,
continue;
const rcCompactCell& c = chf.cells[(ax+bs)+(az+bs)*chf.width];
for (int i = (int)c.index, ni = (int)(c.index+c.count); i < ni; ++i)
for (int i = (int)c.index, ni = (int)(c.index+c.count); i < ni && dmin > 0; ++i)
{
const rcCompactSpan& s = chf.spans[i];
int d = rcAbs(ay - (int)s.y);
if (d < dmin)
{
cx = ax;
cz = az;
ci = i;
startCellX = ax;
startCellY = az;
startSpanIndex = i;
dmin = d;
}
}
}
if (ci != -1)
{
stack.push(cx);
stack.push(cz);
stack.push(ci);
}
}
// Find center of the polygon using flood fill.
int pcx = 0, pcz = 0;
rcAssert(startSpanIndex != -1);
// Find center of the polygon
int pcx = 0, pcy = 0;
for (int j = 0; j < npoly; ++j)
{
pcx += (int)verts[poly[j]*3+0];
pcz += (int)verts[poly[j]*3+2];
pcy += (int)verts[poly[j]*3+2];
}
pcx /= npoly;
pcz /= npoly;
pcy /= npoly;
for (int i = 0; i < stack.size(); i += 3)
{
int cx = stack[i+0];
int cy = stack[i+1];
int idx = cx-hp.xmin+(cy-hp.ymin)*hp.width;
hp.data[idx] = 1;
}
// Use seeds array as a stack for DFS
array.resize(0);
array.push(startCellX);
array.push(startCellY);
array.push(startSpanIndex);
while (stack.size() > 0)
int dirs[] = { 0, 1, 2, 3 };
memset(hp.data, 0, sizeof(unsigned short)*hp.width*hp.height);
// DFS to move to the center. Note that we need a DFS here and can not just move
// directly towards the center without recording intermediate nodes, even though the polygons
// are convex. In very rare we can get stuck due to contour simplification if we do not
// record nodes.
int cx = -1, cy = -1, ci = -1;
while (true)
{
int ci = stack.pop();
int cy = stack.pop();
int cx = stack.pop();
// Check if close to center of the polygon.
if (rcAbs(cx-pcx) <= 1 && rcAbs(cy-pcz) <= 1)
if (array.size() < 3)
{
stack.resize(0);
stack.push(cx);
stack.push(cy);
stack.push(ci);
ctx->log(RC_LOG_WARNING, "Walk towards polygon center failed to reach center");
break;
}
ci = array.pop();
cy = array.pop();
cx = array.pop();
if (cx == pcx && cy == pcy)
break;
// If we are already at the correct X-position, prefer direction
// directly towards the center in the Y-axis; otherwise prefer
// direction in the X-axis
int directDir;
if (cx == pcx)
directDir = rcGetDirForOffset(0, pcy > cy ? 1 : -1);
else
directDir = rcGetDirForOffset(pcx > cx ? 1 : -1, 0);
// Push the direct dir last so we start with this on next iteration
rcSwap(dirs[directDir], dirs[3]);
const rcCompactSpan& cs = chf.spans[ci];
for (int dir = 0; dir < 4; ++dir)
for (int i = 0; i < 4; i++)
{
if (rcGetCon(cs, dir) == RC_NOT_CONNECTED) continue;
const int ax = cx + rcGetDirOffsetX(dir);
const int ay = cy + rcGetDirOffsetY(dir);
if (ax < hp.xmin || ax >= (hp.xmin+hp.width) ||
ay < hp.ymin || ay >= (hp.ymin+hp.height))
int dir = dirs[i];
if (rcGetCon(cs, dir) == RC_NOT_CONNECTED)
continue;
if (hp.data[ax-hp.xmin+(ay-hp.ymin)*hp.width] != 0)
int newX = cx + rcGetDirOffsetX(dir);
int newY = cy + rcGetDirOffsetY(dir);
int hpx = newX - hp.xmin;
int hpy = newY - hp.ymin;
if (hpx < 0 || hpx >= hp.width || hpy < 0 || hpy >= hp.height)
continue;
const int ai = (int)chf.cells[(ax+bs)+(ay+bs)*chf.width].index + rcGetCon(cs, dir);
if (hp.data[hpx+hpy*hp.width] != 0)
continue;
int idx = ax-hp.xmin+(ay-hp.ymin)*hp.width;
hp.data[idx] = 1;
hp.data[hpx+hpy*hp.width] = 1;
array.push(newX);
array.push(newY);
array.push((int)chf.cells[(newX+bs)+(newY+bs)*chf.width].index + rcGetCon(cs, dir));
}
stack.push(ax);
stack.push(ay);
stack.push(ai);
}
rcSwap(dirs[directDir], dirs[3]);
}
array.resize(0);
// getHeightData seeds are given in coordinates with borders
array.push(cx+bs);
array.push(cy+bs);
array.push(ci);
memset(hp.data, 0xff, sizeof(unsigned short)*hp.width*hp.height);
// Mark start locations.
for (int i = 0; i < stack.size(); i += 3)
{
int cx = stack[i+0];
int cy = stack[i+1];
int ci = stack[i+2];
int idx = cx-hp.xmin+(cy-hp.ymin)*hp.width;
const rcCompactSpan& cs = chf.spans[ci];
hp.data[idx] = cs.y;
// getHeightData seeds are given in coordinates with borders
stack[i+0] += bs;
stack[i+1] += bs;
}
hp.data[cx-hp.xmin+(cy-hp.ymin)*hp.width] = cs.y;
}
static void push3(rcIntArray& queue, int v1, int v2, int v3)
{
queue.resize(queue.size() + 3);
queue[queue.size() - 3] = v1;
queue[queue.size() - 2] = v2;
queue[queue.size() - 1] = v3;
}
static void getHeightData(const rcCompactHeightfield& chf,
static void getHeightData(rcContext* ctx, const rcCompactHeightfield& chf,
const unsigned short* poly, const int npoly,
const unsigned short* verts, const int bs,
rcHeightPatch& hp, rcIntArray& stack,
rcHeightPatch& hp, rcIntArray& queue,
int region)
{
// Note: Reads to the compact heightfield are offset by border size (bs)
// since border size offset is already removed from the polymesh vertices.
stack.resize(0);
queue.resize(0);
// Set all heights to RC_UNSET_HEIGHT.
memset(hp.data, 0xff, sizeof(unsigned short)*hp.width*hp.height);
bool empty = true;
// We cannot sample from this poly if it was created from polys
// of different regions. If it was then it could potentially be overlapping
// with polys of that region and the heights sampled here could be wrong.
if (region != RC_MULTIPLE_REGS)
{
// Copy the height from the same region, and mark region borders
// as seed points to fill the rest.
for (int hy = 0; hy < hp.height; hy++)
@ -995,8 +1003,8 @@ static void getHeightData(const rcCompactHeightfield& chf,
for (int hx = 0; hx < hp.width; hx++)
{
int x = hp.xmin + hx + bs;
const rcCompactCell& c = chf.cells[x+y*chf.width];
for (int i = (int)c.index, ni = (int)(c.index+c.count); i < ni; ++i)
const rcCompactCell& c = chf.cells[x + y*chf.width];
for (int i = (int)c.index, ni = (int)(c.index + c.count); i < ni; ++i)
{
const rcCompactSpan& s = chf.spans[i];
if (s.reg == region)
@ -1014,7 +1022,7 @@ static void getHeightData(const rcCompactHeightfield& chf,
{
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);
const int ai = (int)chf.cells[ax + ay*chf.width].index + rcGetCon(s, dir);
const rcCompactSpan& as = chf.spans[ai];
if (as.reg != region)
{
@ -1024,37 +1032,38 @@ static void getHeightData(const rcCompactHeightfield& chf,
}
}
if (border)
{
stack.push(x);
stack.push(y);
stack.push(i);
}
push3(queue, x, y, i);
break;
}
}
}
}
}
// if the polygon does not contian any points from the current region (rare, but happens)
// then use the cells closest to the polygon vertices as seeds to fill the height field
// if the polygon does not contain any points from the current region (rare, but happens)
// or if it could potentially be overlapping polygons of the same region,
// then use the center as the seed point.
if (empty)
getHeightDataSeedsFromVertices(chf, poly, npoly, verts, bs, hp, stack);
seedArrayWithPolyCenter(ctx, chf, poly, npoly, verts, bs, hp, queue);
static const int RETRACT_SIZE = 256;
int head = 0;
while (head*3 < stack.size())
// We assume the seed is centered in the polygon, so a BFS to collect
// height data will ensure we do not move onto overlapping polygons and
// sample wrong heights.
while (head*3 < queue.size())
{
int cx = stack[head*3+0];
int cy = stack[head*3+1];
int ci = stack[head*3+2];
int cx = queue[head*3+0];
int cy = queue[head*3+1];
int ci = queue[head*3+2];
head++;
if (head >= RETRACT_SIZE)
{
head = 0;
if (stack.size() > RETRACT_SIZE*3)
memmove(&stack[0], &stack[RETRACT_SIZE*3], sizeof(int)*(stack.size()-RETRACT_SIZE*3));
stack.resize(stack.size()-RETRACT_SIZE*3);
if (queue.size() > RETRACT_SIZE*3)
memmove(&queue[0], &queue[RETRACT_SIZE*3], sizeof(int)*(queue.size()-RETRACT_SIZE*3));
queue.resize(queue.size()-RETRACT_SIZE*3);
}
const rcCompactSpan& cs = chf.spans[ci];
@ -1067,7 +1076,7 @@ static void getHeightData(const rcCompactHeightfield& chf,
const int hx = ax - hp.xmin - bs;
const int hy = ay - hp.ymin - bs;
if (hx < 0 || hx >= hp.width || hy < 0 || hy >= hp.height)
if ((unsigned int)hx >= (unsigned int)hp.width || (unsigned int)hy >= (unsigned int)hp.height)
continue;
if (hp.data[hx + hy*hp.width] != RC_UNSET_HEIGHT)
@ -1078,9 +1087,7 @@ static void getHeightData(const rcCompactHeightfield& chf,
hp.data[hx + hy*hp.width] = as.y;
stack.push(ax);
stack.push(ay);
stack.push(ai);
push3(queue, ax, ay, ai);
}
}
}
@ -1133,7 +1140,7 @@ bool rcBuildPolyMeshDetail(rcContext* ctx, const rcPolyMesh& mesh, const rcCompa
rcIntArray edges(64);
rcIntArray tris(512);
rcIntArray stack(512);
rcIntArray arr(512);
rcIntArray samples(512);
float verts[256*3];
rcHeightPatch hp;
@ -1240,7 +1247,7 @@ bool rcBuildPolyMeshDetail(rcContext* ctx, const rcPolyMesh& mesh, const rcCompa
hp.ymin = bounds[i*4+2];
hp.width = bounds[i*4+1]-bounds[i*4+0];
hp.height = bounds[i*4+3]-bounds[i*4+2];
getHeightData(chf, p, npoly, mesh.verts, borderSize, hp, stack, mesh.regs[i]);
getHeightData(ctx, chf, p, npoly, mesh.verts, borderSize, hp, arr, mesh.regs[i]);
// Build detail mesh.
int nverts = 0;