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Modularized fork of Processing Core libraries.
/*
* Portions Copyright (C) 2003-2006 Sun Microsystems, Inc.
* All rights reserved.
*/
/*
** License Applicability. Except to the extent portions of this file are
** made subject to an alternative license as permitted in the SGI Free
** Software License B, Version 2.0 (the "License"), the contents of this
** file are subject only to the provisions of the License. You may not use
** this file except in compliance with the License. You may obtain a copy
** of the License at Silicon Graphics, Inc., attn: Legal Services, 1600
** Amphitheatre Parkway, Mountain View, CA 94043-1351, or at:
**
** http://oss.sgi.com/projects/FreeB
**
** Note that, as provided in the License, the Software is distributed on an
** "AS IS" basis, with ALL EXPRESS AND IMPLIED WARRANTIES AND CONDITIONS
** DISCLAIMED, INCLUDING, WITHOUT LIMITATION, ANY IMPLIED WARRANTIES AND
** CONDITIONS OF MERCHANTABILITY, SATISFACTORY QUALITY, FITNESS FOR A
** PARTICULAR PURPOSE, AND NON-INFRINGEMENT.
**
** NOTE: The Original Code (as defined below) has been licensed to Sun
** Microsystems, Inc. ("Sun") under the SGI Free Software License B
** (Version 1.1), shown above ("SGI License"). Pursuant to Section
** 3.2(3) of the SGI License, Sun is distributing the Covered Code to
** you under an alternative license ("Alternative License"). This
** Alternative License includes all of the provisions of the SGI License
** except that Section 2.2 and 11 are omitted. Any differences between
** the Alternative License and the SGI License are offered solely by Sun
** and not by SGI.
**
** Original Code. The Original Code is: OpenGL Sample Implementation,
** Version 1.2.1, released January 26, 2000, developed by Silicon Graphics,
** Inc. The Original Code is Copyright (c) 1991-2000 Silicon Graphics, Inc.
** Copyright in any portions created by third parties is as indicated
** elsewhere herein. All Rights Reserved.
**
** Additional Notice Provisions: The application programming interfaces
** established by SGI in conjunction with the Original Code are The
** OpenGL(R) Graphics System: A Specification (Version 1.2.1), released
** April 1, 1999; The OpenGL(R) Graphics System Utility Library (Version
** 1.3), released November 4, 1998; and OpenGL(R) Graphics with the X
** Window System(R) (Version 1.3), released October 19, 1998. This software
** was created using the OpenGL(R) version 1.2.1 Sample Implementation
** published by SGI, but has not been independently verified as being
** compliant with the OpenGL(R) version 1.2.1 Specification.
**
** Author: Eric Veach, July 1994
** Java Port: Pepijn Van Eeckhoudt, July 2003
** Java Port: Nathan Parker Burg, August 2003
** Processing integration: Andres Colubri, February 2012
*/
package processing.lwjgl.tess;
class PriorityQHeap extends PriorityQ {
PriorityQ.PQnode[] nodes;
PriorityQ.PQhandleElem[] handles;
int size, max;
int freeList;
boolean initialized;
PriorityQ.Leq leq;
/* really __gl_pqHeapNewPriorityQ */
public PriorityQHeap(PriorityQ.Leq leq) {
size = 0;
max = PriorityQ.INIT_SIZE;
nodes = new PriorityQ.PQnode[PriorityQ.INIT_SIZE + 1];
for (int i = 0; i < nodes.length; i++) {
nodes[i] = new PQnode();
}
handles = new PriorityQ.PQhandleElem[PriorityQ.INIT_SIZE + 1];
for (int i = 0; i < handles.length; i++) {
handles[i] = new PQhandleElem();
}
initialized = false;
freeList = 0;
this.leq = leq;
nodes[1].handle = 1; /* so that Minimum() returns NULL */
handles[1].key = null;
}
/* really __gl_pqHeapDeletePriorityQ */
@Override
void pqDeletePriorityQ() {
handles = null;
nodes = null;
}
void FloatDown(int curr) {
PriorityQ.PQnode[] n = nodes;
PriorityQ.PQhandleElem[] h = handles;
int hCurr, hChild;
int child;
hCurr = n[curr].handle;
for (; ;) {
child = curr << 1;
if (child < size && LEQ(leq, h[n[child + 1].handle].key,
h[n[child].handle].key)) {
++child;
}
assert (child <= max);
hChild = n[child].handle;
if (child > size || LEQ(leq, h[hCurr].key, h[hChild].key)) {
n[curr].handle = hCurr;
h[hCurr].node = curr;
break;
}
n[curr].handle = hChild;
h[hChild].node = curr;
curr = child;
}
}
void FloatUp(int curr) {
PriorityQ.PQnode[] n = nodes;
PriorityQ.PQhandleElem[] h = handles;
int hCurr, hParent;
int parent;
hCurr = n[curr].handle;
for (; ;) {
parent = curr >> 1;
hParent = n[parent].handle;
if (parent == 0 || LEQ(leq, h[hParent].key, h[hCurr].key)) {
n[curr].handle = hCurr;
h[hCurr].node = curr;
break;
}
n[curr].handle = hParent;
h[hParent].node = curr;
curr = parent;
}
}
/* really __gl_pqHeapInit */
@Override
boolean pqInit() {
int i;
/* This method of building a heap is O(n), rather than O(n lg n). */
for (i = size; i >= 1; --i) {
FloatDown(i);
}
initialized = true;
return true;
}
/* really __gl_pqHeapInsert */
/* returns LONG_MAX iff out of memory */
@Override
int pqInsert(Object keyNew) {
int curr;
int free;
curr = ++size;
if ((curr * 2) > max) {
PriorityQ.PQnode[] saveNodes = nodes;
PriorityQ.PQhandleElem[] saveHandles = handles;
/* If the heap overflows, double its size. */
max <<= 1;
// pq->nodes = (PQnode *)memRealloc( pq->nodes, (size_t) ((pq->max + 1) * sizeof( pq->nodes[0] )));
PriorityQ.PQnode[] pqNodes = new PriorityQ.PQnode[max + 1];
System.arraycopy( nodes, 0, pqNodes, 0, nodes.length );
for (int i = nodes.length; i < pqNodes.length; i++) {
pqNodes[i] = new PQnode();
}
nodes = pqNodes;
if (nodes == null) {
nodes = saveNodes; /* restore ptr to free upon return */
return Integer.MAX_VALUE;
}
// pq->handles = (PQhandleElem *)memRealloc( pq->handles,(size_t)((pq->max + 1) * sizeof( pq->handles[0] )));
PriorityQ.PQhandleElem[] pqHandles = new PriorityQ.PQhandleElem[max + 1];
System.arraycopy( handles, 0, pqHandles, 0, handles.length );
for (int i = handles.length; i < pqHandles.length; i++) {
pqHandles[i] = new PQhandleElem();
}
handles = pqHandles;
if (handles == null) {
handles = saveHandles; /* restore ptr to free upon return */
return Integer.MAX_VALUE;
}
}
if (freeList == 0) {
free = curr;
} else {
free = freeList;
freeList = handles[free].node;
}
nodes[curr].handle = free;
handles[free].node = curr;
handles[free].key = keyNew;
if (initialized) {
FloatUp(curr);
}
assert (free != Integer.MAX_VALUE);
return free;
}
/* really __gl_pqHeapExtractMin */
@Override
Object pqExtractMin() {
PriorityQ.PQnode[] n = nodes;
PriorityQ.PQhandleElem[] h = handles;
int hMin = n[1].handle;
Object min = h[hMin].key;
if (size > 0) {
n[1].handle = n[size].handle;
h[n[1].handle].node = 1;
h[hMin].key = null;
h[hMin].node = freeList;
freeList = hMin;
if (--size > 0) {
FloatDown(1);
}
}
return min;
}
/* really __gl_pqHeapDelete */
@Override
void pqDelete(int hCurr) {
PriorityQ.PQnode[] n = nodes;
PriorityQ.PQhandleElem[] h = handles;
int curr;
assert (hCurr >= 1 && hCurr <= max && h[hCurr].key != null);
curr = h[hCurr].node;
n[curr].handle = n[size].handle;
h[n[curr].handle].node = curr;
if (curr <= --size) {
if (curr <= 1 || LEQ(leq, h[n[curr >> 1].handle].key, h[n[curr].handle].key)) {
FloatDown(curr);
} else {
FloatUp(curr);
}
}
h[hCurr].key = null;
h[hCurr].node = freeList;
freeList = hCurr;
}
@Override
Object pqMinimum() {
return handles[nodes[1].handle].key;
}
@Override
boolean pqIsEmpty() {
return size == 0;
}
}
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