vcglib/apps/nexus/extraction.cpp

158 lines
4.0 KiB
C++

#include "extraction.h"
#include "metric.h"
#include "nexusmt.h"
#include <algorithm>
using namespace std;
using namespace nxs;
Extraction::Extraction(): target_error(4.0f), extr_max(0xffffffff),
draw_max(640), disk_max(100) {
metric = new FrustumMetric;
}
Extraction::~Extraction() {
if(metric) delete metric;
}
void Extraction::Extract(NexusMt *_mt) {
mt = _mt;
//clear statistics
extr_used = draw_used = disk_used = 0;
//first we clear the visited flags
visited.clear();
visited.resize(mt->history.n_nodes(), false);
heap.clear();
History::Node *root = mt->history.Root();
HeapNode hroot(root, 0);
Diff(hroot);
extr_used += hroot.extr;
draw_used += hroot.draw;
disk_used += hroot.disk;
Visit(root);
while(heap.size()) {
pop_heap(heap.begin(), heap.end());
HeapNode hnode = heap.back();
heap.pop_back();
History::Node *node = hnode.node;
unsigned int id = node - root;
if(visited[id]) continue;
if(Expand(hnode)) {
extr_used += hnode.extr;
draw_used += hnode.draw;
disk_used += hnode.disk;
Visit(node);
}
}
Select();
}
void Extraction::Select() {
selected.clear();
History::Node *root = mt->history.Root();
History::Node *nodes = mt->history.nodes;
for(unsigned int i = 0; i < visited.size(); i++) {
if(!visited[i]) continue;
History::Node &node = nodes[i];
History::Node::iterator n;
for(n = node.out_begin(); n != node.out_end(); n++) {
unsigned int n_out = (*n).node - root;
if(!visited[n_out]) {
History::Link &link = *n;
for(History::Link::iterator k = link.begin(); k != link.end(); k++) {
unsigned int patch = (*k).patch;
selected.push_back(patch);
}
}
}
}
}
void Extraction::Visit(History::Node *node) {
History::Node *root = mt->history.Root();
unsigned int n_node = node - root;
if(visited[n_node]) return;
visited[n_node] = true;
History::Node::iterator i;
for(i = node->in_begin(); i != node->in_end(); i++) {
unsigned int n_in = (*i).node - root;
if(visited[n_in]) continue;
HeapNode hin((*i).node, 0);
Diff(hin);
extr_used += hin.extr;
draw_used += hin.draw;
disk_used += hin.disk;
Visit((*i).node);
}
for(i = node->out_begin(); i != node->out_end(); i++) {
float maxerror = 0;
History::Link &link = *i;
for(History::Link::iterator k = link.begin(); k != link.end(); k++) {
Entry &entry = (*mt)[(*k).patch];
float error = metric->GetError(entry);
if(error > maxerror) maxerror = error;
}
//TODO this check may be dangerous for non saturating things...
if(maxerror > target_error) {
HeapNode hnode((*i).node, maxerror);
Diff(hnode);
heap.push_back(hnode);
push_heap(heap.begin(), heap.end());
}
}
}
bool Extraction::Expand(HeapNode &node) {
if(extr_used >= extr_max) return false;
if(draw_used >= draw_max) return false;
// if(disk_used >= disk_max) return false;
return node.error > target_error;
}
void Extraction::Diff(HeapNode &hnode) {
History::Node &node = *(hnode.node);
History::Node::iterator i;
for(i = node.in_begin(); i != node.in_end(); i++) {
History::Link &link = *i;
for(History::Link::iterator k = link.begin(); k != link.end(); k++) {
unsigned int patch = (*k).patch;
Entry &entry = (*mt)[patch];
hnode.extr -= entry.ram_size;
vcg::Sphere3f &sphere = entry.sphere;
if(!frustum.IsOutside(sphere.Center(), sphere.Radius()))
hnode.draw -= entry.ram_size;
if(!entry.patch)
hnode.disk -= entry.disk_size;
}
}
for(i = node.out_begin(); i != node.out_end(); i++) {
History::Link &link = *i;
for(History::Link::iterator k = link.begin(); k != link.end(); k++) {
unsigned int patch = (*k).patch;
Entry &entry = (*mt)[patch];
hnode.extr += entry.ram_size;
vcg::Sphere3f &sphere = entry.sphere;
if(!frustum.IsOutside(sphere.Center(), sphere.Radius()))
hnode.draw += entry.ram_size;
if(!entry.patch)
hnode.disk += entry.disk_size;
}
}
}