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fix bug w/ large clumps per cluster;

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reduce time spent on global union-find by skipping clumps that don't touch edges
This commit is contained in:
Sean Barrett 2016-04-17 08:12:52 -07:00
parent 484605343f
commit d1eba33305
2 changed files with 133 additions and 13 deletions
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120
stb_connected_components.h
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@ -353,7 +353,7 @@ static void stbcc__build_connected_components_for_clumps(stbcc_grid *g)
for (j=0; j < STBCC__CLUSTER_COUNT_Y; ++j) {
for (i=0; i < STBCC__CLUSTER_COUNT_X; ++i) {
stbcc__cluster *cluster = &g->cluster[j][i];
for (k=0; k < (int) cluster->num_clumps; ++k) {
for (k=0; k < (int) cluster->num_edge_clumps; ++k) {
stbcc__global_clumpid m;
m.f.clump_index = k;
m.f.cluster_x = i;
@ -367,7 +367,7 @@ static void stbcc__build_connected_components_for_clumps(stbcc_grid *g)
for (j=0; j < STBCC__CLUSTER_COUNT_Y; ++j) {
for (i=0; i < STBCC__CLUSTER_COUNT_X; ++i) {
stbcc__cluster *cluster = &g->cluster[j][i];
for (k=0; k < (int) cluster->num_clumps; ++k) {
for (k=0; k < (int) cluster->num_edge_clumps; ++k) {
stbcc__clump *clump = &cluster->clump[k];
stbcc__unpacked_clumpid m;
stbcc__relative_clumpid *adj;
@ -388,7 +388,7 @@ static void stbcc__build_connected_components_for_clumps(stbcc_grid *g)
for (j=0; j < STBCC__CLUSTER_COUNT_Y; ++j) {
for (i=0; i < STBCC__CLUSTER_COUNT_X; ++i) {
stbcc__cluster *cluster = &g->cluster[j][i];
for (k=0; k < (int) cluster->num_clumps; ++k) {
for (k=0; k < (int) cluster->num_edge_clumps; ++k) {
stbcc__global_clumpid m;
m.f.clump_index = k;
m.f.cluster_x = i;
@ -507,10 +507,15 @@ static void stbcc__build_all_connections_for_cluster(stbcc_grid *g, int cx, int
}
assert(total <= STBCC__CLUSTER_ADJACENCY_COUNT);
assert(g->w);
stbcc__add_connections_to_adjacent_cluster(g, cx, cy, -1, 0);
assert(g->w);
stbcc__add_connections_to_adjacent_cluster(g, cx, cy, 1, 0);
assert(g->w);
stbcc__add_connections_to_adjacent_cluster(g, cx, cy, 0,-1);
assert(g->w);
stbcc__add_connections_to_adjacent_cluster(g, cx, cy, 0, 1);
assert(g->w);
// make sure all of the above succeeded.
assert(g->cluster[cy][cx].rebuild_adjacency == 0);
}
@ -654,11 +659,13 @@ static void stbcc__add_clump_connection(stbcc_grid *g, int x1, int y1, int x2, i
cluster = &g->cluster[cy1][cx1];
clump = &cluster->clump[c1];
assert(clump->num_adjacent <= clump->max_adjacent);
if (clump->num_adjacent == clump->max_adjacent)
g->cluster[cy1][cx1].rebuild_adjacency = 1;
else {
stbcc__relative_clumpid *adj = &cluster->adjacency_storage[clump->adjacent_clump_list_index];
assert(clump->num_adjacent < STBCC__MAX_EXITS_PER_CLUMP);
assert(clump->adjacent_clump_list_index + clump->num_adjacent <= STBCC__CLUSTER_ADJACENCY_COUNT);
adj[clump->num_adjacent++] = rc;
}
}
@ -755,6 +762,7 @@ static void stbcc__add_connections_to_adjacent_cluster(stbcc_grid *g, int cx, in
if (STBCC__MAP_OPEN(g, x+i, y+j) && STBCC__MAP_OPEN(g, x+i+dx, y+j+dy)) {
stbcc__clumpid c = g->clump_for_node[y+j+dy][x+i+dx];
if (0 == (connected[c>>3] & (1 << (c & 7)))) {
assert((c>>3) < sizeof(connected));
connected[c>>3] |= 1 << (c & 7);
stbcc__add_clump_connection(g, x+i, y+j, x+i+dx, y+j+dy);
if (g->cluster[cy][cx].rebuild_adjacency)
@ -844,6 +852,14 @@ static void stbcc__incluster_union(stbcc__cluster_build_info *cbi, int x1, int y
cbi->parent[p.y][p.x] = q;
}
static void stbcc__switch_root(stbcc__cluster_build_info *cbi, int x, int y, stbcc__tinypoint p)
{
cbi->parent[p.y][p.x].x = x;
cbi->parent[p.y][p.x].y = y;
cbi->parent[y][x].x = x;
cbi->parent[y][x].y = y;
}
static void stbcc__build_clumps_for_cluster(stbcc_grid *g, int cx, int cy)
{
stbcc__cluster *c;
@ -874,9 +890,69 @@ static void stbcc__build_clumps_for_cluster(stbcc_grid *g, int cx, int cy)
stbcc__incluster_union(&cbi, i,j, i+1,j);
}
// label all non-empty leaders
// label all non-empty clumps along edges so that all edge clumps are first
// in list; this means in degenerate case we can skip traversing non-edge clumps.
// because in the first pass we only label leaders, we swap the leader to the
// edge first
// first put solid labels on all the edges; these will get overwritten if they're open
for (j=0; j < STBCC__CLUSTER_SIZE_Y; ++j)
cbi.label[j][0] = cbi.label[j][STBCC__CLUSTER_SIZE_X-1] = STBCC__NULL_CLUMPID;
for (i=0; i < STBCC__CLUSTER_SIZE_X; ++i)
cbi.label[0][i] = cbi.label[STBCC__CLUSTER_SIZE_Y-1][i] = STBCC__NULL_CLUMPID;
for (j=0; j < STBCC__CLUSTER_SIZE_Y; ++j) {
for (i=0; i < STBCC__CLUSTER_SIZE_X; ++i) {
i = 0;
if (STBCC__MAP_OPEN(g, x+i, y+j)) {
stbcc__tinypoint p = stbcc__incluster_find(&cbi, i,j);
if (p.x == i && p.y == j)
// if this is the leader, give it a label
cbi.label[j][i] = label++;
else if (!(p.x == 0 || p.x == STBCC__CLUSTER_SIZE_X-1 || p.y == 0 || p.y == STBCC__CLUSTER_SIZE_Y-1)) {
// if leader is in interior, promote this edge node to leader and label
stbcc__switch_root(&cbi, i, j, p);
cbi.label[j][i] = label++;
}
// else if leader is on edge, do nothing (it'll get labelled when we reach it)
}
i = STBCC__CLUSTER_SIZE_X-1;
if (STBCC__MAP_OPEN(g, x+i, y+j)) {
stbcc__tinypoint p = stbcc__incluster_find(&cbi, i,j);
if (p.x == i && p.y == j)
cbi.label[j][i] = label++;
else if (!(p.x == 0 || p.x == STBCC__CLUSTER_SIZE_X-1 || p.y == 0 || p.y == STBCC__CLUSTER_SIZE_Y-1)) {
stbcc__switch_root(&cbi, i, j, p);
cbi.label[j][i] = label++;
}
}
}
for (i=1; i < STBCC__CLUSTER_SIZE_Y-1; ++i) {
j = 0;
if (STBCC__MAP_OPEN(g, x+i, y+j)) {
stbcc__tinypoint p = stbcc__incluster_find(&cbi, i,j);
if (p.x == i && p.y == j)
cbi.label[j][i] = label++;
else if (!(p.x == 0 || p.x == STBCC__CLUSTER_SIZE_X-1 || p.y == 0 || p.y == STBCC__CLUSTER_SIZE_Y-1)) {
stbcc__switch_root(&cbi, i, j, p);
cbi.label[j][i] = label++;
}
}
j = STBCC__CLUSTER_SIZE_Y-1;
if (STBCC__MAP_OPEN(g, x+i, y+j)) {
stbcc__tinypoint p = stbcc__incluster_find(&cbi, i,j);
if (p.x == i && p.y == j)
cbi.label[j][i] = label++;
else if (!(p.x == 0 || p.x == STBCC__CLUSTER_SIZE_X-1 || p.y == 0 || p.y == STBCC__CLUSTER_SIZE_Y-1)) {
stbcc__switch_root(&cbi, i, j, p);
cbi.label[j][i] = label++;
}
}
}
// label any internal clusters
for (j=1; j < STBCC__CLUSTER_SIZE_Y-1; ++j) {
for (i=1; i < STBCC__CLUSTER_SIZE_X-1; ++i) {
stbcc__tinypoint p = cbi.parent[j][i];
if (p.x == i && p.y == j)
if (STBCC__MAP_OPEN(g,x+i,y+j))
@ -894,13 +970,17 @@ static void stbcc__build_clumps_for_cluster(stbcc_grid *g, int cx, int cy)
if (STBCC__MAP_OPEN(g,x+i,y+j))
cbi.label[j][i] = cbi.label[p.y][p.x];
}
if (STBCC__MAP_OPEN(g,x+i,y+j))
assert(cbi.label[j][i] != STBCC__NULL_CLUMPID);
}
}
c = &g->cluster[cy][cx];
c->num_clumps = label;
for (i=0; i < label; ++i)
for (i=0; i < label; ++i) {
c->clump[i].num_adjacent = 0;
c->clump[i].on_edge = 0;
}
for (j=0; j < STBCC__CLUSTER_SIZE_Y; ++j)
for (i=0; i < STBCC__CLUSTER_SIZE_X; ++i) {
@ -910,20 +990,24 @@ static void stbcc__build_clumps_for_cluster(stbcc_grid *g, int cx, int cy)
for (i=0; i < STBCC__CLUSTER_SIZE_X; ++i) {
int d = cbi.label[0][i];
if (d != STBCC__NULL_CLUMPID)
if (d != STBCC__NULL_CLUMPID) {
c->clump[d].on_edge = 1;
}
d = cbi.label[STBCC__CLUSTER_SIZE_Y-1][i];
if (d != STBCC__NULL_CLUMPID)
if (d != STBCC__NULL_CLUMPID) {
c->clump[d].on_edge = 1;
}
}
for (j=0; j < STBCC__CLUSTER_SIZE_Y; ++j) {
for (j=1; j < STBCC__CLUSTER_SIZE_Y-1; ++j) {
int d = cbi.label[j][0];
if (d != STBCC__NULL_CLUMPID)
if (d != STBCC__NULL_CLUMPID) {
c->clump[d].on_edge = 1;
}
d = cbi.label[j][STBCC__CLUSTER_SIZE_X-1];
if (d != STBCC__NULL_CLUMPID)
if (d != STBCC__NULL_CLUMPID) {
c->clump[d].on_edge = 1;
}
}
num_on_edge = 0;
@ -931,6 +1015,20 @@ static void stbcc__build_clumps_for_cluster(stbcc_grid *g, int cx, int cy)
num_on_edge += c->clump[i].on_edge;
c->num_edge_clumps = num_on_edge;
for (i=0; i < (int) c->num_edge_clumps; ++i)
assert(c->clump[i].on_edge);
for (; i < (int) c->num_clumps; ++i)
assert(!c->clump[i].on_edge);
// set the global label for all interior clumps since they can't have connections, so we don't have to do this on the global pass
for (i=(int) c->num_edge_clumps; i < (int) c->num_clumps; ++i) {
stbcc__global_clumpid gc;
gc.f.cluster_x = cx;
gc.f.cluster_y = cy;
gc.f.clump_index = i;
c->clump[i].global_label = gc;
}
c->rebuild_adjacency = 1; // flag that it has no valid adjacency data
}

26
tests/grid_reachability.c
View File

@ -143,12 +143,16 @@ int main(int argc, char **argv)
assert(map);
stbi_write_png("tests/output/stbcc/reference.png", w, h, 1, map, 0);
for (j=0; j < h; ++j)
for (i=0; i < w; ++i)
map[j*w+i] = ~map[j*w+i];
for (i=0; i < w; ++i)
for (j=0; j < h; ++j)
map[j*w+i] = (i ^ j) & 1 ? 255 : 0;
stbi_write_png("tests/output/stbcc/reference.png", w, h, 1, map, 0);
//reference(map, w, h);
_mkdir("tests/output/stbcc");
@ -183,6 +187,24 @@ int main(int argc, char **argv)
printf("Cluster size: %d,%d\n", STBCC__CLUSTER_SIZE_X, STBCC__CLUSTER_SIZE_Y);
#if 1
for (j=0; j < 10; ++j) {
for (i=0; i < 5000; ++i) {
loc[i][0] = stb_rand() % w;
loc[i][1] = stb_rand() % h;
}
start_timer("updating 500");
for (i=0; i < 500; ++i) {
if (stbcc_query_grid_open(g, loc[i][0], loc[i][1]))
stbcc_update_grid(g, loc[i][0], loc[i][1], 1);
else
stbcc_update_grid(g, loc[i][0], loc[i][1], 0);
}
end_timer();
write_map(g, w, h, stb_sprintf("tests/output/stbcc/update_random_%d.png", j*i));
}
#endif
#if 0
start_timer("removing");
count = 0;
for (i=0; i < 1800; ++i) {