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-rw-r--r--src/3rdparty/adaptagrams/libvpsc/cbuffer.cpp95
1 files changed, 95 insertions, 0 deletions
diff --git a/src/3rdparty/adaptagrams/libvpsc/cbuffer.cpp b/src/3rdparty/adaptagrams/libvpsc/cbuffer.cpp
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+++ b/src/3rdparty/adaptagrams/libvpsc/cbuffer.cpp
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+/*
+ * vim: ts=4 sw=4 et tw=0 wm=0
+ *
+ * libvpsc - A solver for the problem of Variable Placement with
+ * Separation Constraints.
+ *
+ * Copyright (C) 2005-2008 Monash University
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ * See the file LICENSE.LGPL distributed with the library.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ *
+ * Author(s): Tim Dwyer
+ *
+*/
+
+#include <cfloat>
+
+#include "libvpsc/cbuffer.h"
+#include "libvpsc/constraint.h"
+#include "libvpsc/assertions.h"
+
+namespace vpsc {
+ static const double ZERO_UPPERBOUND=-0.0000001;
+ void CBuffer::load() {
+ size=0;
+ double buffMaxSlack=-DBL_MAX;
+ unsigned buffMaxSlackPos=0;
+ for(Constraints::iterator i=master_list.begin();
+ i!=master_list.end();++i) {
+ Constraint *c=*i;
+ double slack = c->slack();
+ if(c->equality||slack<ZERO_UPPERBOUND) {
+ if(size<maxsize) {
+ // make sure buffer is full
+ buffer[size]=c;
+ if(slack>buffMaxSlack) {
+ buffMaxSlack=slack;
+ buffMaxSlackPos=size;
+ }
+ size++;
+ } else {
+ // if c is more violated than the least violated
+ // constraint in the buffer then replace it
+ buffer[buffMaxSlackPos]=c;
+ // need to search the buffer for the new least
+ // violated constraint
+ buffMaxSlack=-DBL_MAX;
+ for(unsigned i=0;i<size;i++) {
+ c=buffer[i];
+ if(!c->equality&&buffMaxSlack < c->slack()) {
+ buffMaxSlack = slack;
+ buffMaxSlackPos = i;
+ }
+ }
+ }
+ }
+ }
+ }
+ Constraint* CBuffer::mostViolated() {
+ Constraint* v=nullptr;
+ while(true) {
+ if(size==0) {
+ load();
+ if(size==0) break;
+ }
+ double minSlack=DBL_MAX;
+ int i,deletePos=-1;
+ for(i=0;i<(int)size;i++) {
+ Constraint *c=buffer[i];
+ double slack = c->slack();
+ if(!(c->equality||slack < ZERO_UPPERBOUND)) {
+ COLA_ASSERT(size>0);
+ buffer[i--]=buffer[--size];
+ } else if(c->equality||slack < minSlack) {
+ v=c;
+ deletePos=i;
+ minSlack=slack;
+ }
+ }
+ if(deletePos>=0) {
+ COLA_ASSERT(size>0);
+ buffer[deletePos]=buffer[--size];
+ break;
+ }
+ }
+ return v;
+ }
+}