summaryrefslogtreecommitdiff
path: root/src/glu/sgi/libnurbs/nurbtess/searchTree.cc
blob: 1865755a484a2ad7cdd151a7cbbf0a72a5b82f77 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
/*
** 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 1.1 (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.
** 
** 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.
**
*/
/*
*/

#include <stdlib.h>
#include <stdio.h>
#include "zlassert.h"

#include "searchTree.h"

#define max(a,b) ((a>b)? a:b)

treeNode* TreeNodeMake(void *key)
{
  treeNode *ret = (treeNode*) malloc(sizeof(treeNode));
  assert(ret);
  ret->key = key;
  ret->parent = NULL;
  ret->left = NULL;
  ret->right = NULL;
  return ret;
}

void TreeNodeDeleteSingleNode(treeNode* node)
{
  free(node);
}

void TreeNodeDeleteWholeTree(treeNode* node)
{
  if(node == NULL) return;
  TreeNodeDeleteWholeTree(node->left);
  TreeNodeDeleteWholeTree(node->right);
  TreeNodeDeleteSingleNode(node);
}

void TreeNodePrint(treeNode* node, 
		   void (*keyPrint) (void*))
{
  if(node ==NULL) return;
  TreeNodePrint(node->left, keyPrint);
  keyPrint(node->key);
  TreeNodePrint(node->right, keyPrint);  
}

int TreeNodeDepth(treeNode* root)
{
  if(root == NULL) return 0;
  else{
    int leftdepth = TreeNodeDepth(root->left);
    int rightdepth = TreeNodeDepth(root->right);  
    return 1 + max(leftdepth, rightdepth);
  }
}

/*return the node with the key.
 *NULL is returned if not found
 */
treeNode* TreeNodeFind(treeNode* tree, void* key,
		       int (*compkey) (void*, void*)) 	       
{
  if(tree == NULL) 
    return NULL;
  if(key == tree->key)
    return tree;
  else if(compkey(key, tree->key) < 0)
    return TreeNodeFind(tree->left, key, compkey);
  else 
    return TreeNodeFind(tree->right, key, compkey);    
}


treeNode* TreeNodeInsert(treeNode* root, treeNode* newnode,
		    int (*compkey) (void *, void *))
{
  treeNode *y = NULL;
  treeNode *x = root;
  /*going down the tree from the root.
   *x traces the path, y is the parent of x.
   */
  while (x != NULL){
    y = x;
    if(compkey(newnode->key,x->key) < 0) /*if newnode < x*/
      x = x->left;
    else 
      x = x->right;
  }

  /*now y has the property that 
   * if newnode < y, then y->left is NULL
   * if newnode > y, then y->right is NULL.
   *So we want to isnert newnode to be the child of y
   */
  newnode->parent = y;
  if(y == NULL) 
    return newnode;
  else if( compkey(newnode->key, y->key) <0)
    {
      y->left = newnode;
    }
  else
    {
      y->right = newnode;
    }

  return root;
}
    
treeNode* TreeNodeDeleteSingleNode(treeNode* tree, treeNode* node)
{
  treeNode* y;
  treeNode* x;
  treeNode* ret;
  if(node==NULL) return tree;

  if(node->left == NULL || node->right == NULL) {

    y = node;
    if(y->left != NULL) 
      x = y->left;
    else
      x = y->right;

    if( x != NULL)
      x->parent = y->parent;

    if(y->parent == NULL) /*y is the root which has at most one child x*/
      ret = x;
    else /*y is not the root*/
      {
	if(y == y->parent->left) 
	  y->parent->left = x;
	else
	  y->parent->right = x;
	ret =  tree;
      }
  }
  else { /*node has two children*/

     y = TreeNodeSuccessor(node);
     assert(y->left == NULL);

     if(y == node->right) /*y is the right child if node*/
       {
	 y->parent = node->parent;
	 y->left = node->left;
	 node->left->parent = y;
	 
       }
     else  /*y != node->right*/
       {
	 x = y->right;
	 if(x!= NULL)
	   x->parent = y->parent;

	 assert(y->parent != NULL);
	 if(y == y->parent->left) 
	   y->parent->left = x;
	 else
	   y->parent->right = x;
	 /*move y to the position of node*/
	 y->parent = node->parent;
	 y->left = node->left;
	 y->right = node->right;
	 node->left->parent = y;
	 node->right->parent = y;
       }
    if(node->parent != NULL) {
      if(node->parent->left == node)
	node->parent->left = y;
      else
	node->parent->right = y;
      ret = tree; /*the root if the tree doesn't change*/
    }
    else /*node->parent is NULL: node is the root*/
      ret = y;    
  }

  /*finally free the node, and return the new root*/
  TreeNodeDeleteSingleNode(node);
  return ret;
}
     

/*the minimum node in the tree rooted by node
 */
treeNode* TreeNodeMinimum(treeNode* node)
{
  treeNode* temp = node;
  if(temp == NULL) return NULL;
  while(temp->left != NULL) {
    temp = temp->left;
  }
  return temp;
}

/*the maximum node in the tree rooted by node
 */
treeNode* TreeNodeMaximum(treeNode* node)
{
  treeNode* temp = node;
  if(temp == NULL) return NULL;
  while(temp->right != NULL) {
    temp = temp->right;
  }
  return temp;
}

/*return the first node (in sorted order) which is to the right of this node
 */
treeNode* TreeNodeSuccessor(treeNode* node)
{
  if(node == NULL) return NULL;
  if(node->right != NULL)
    return TreeNodeMinimum(node->right);
  else{ /*node->right is NULL*/

    /*find the first right-ancestor*/
    treeNode *y = node->parent;
    treeNode* x = node;
    while(y != NULL && x == y->right) /*if y is a left parent of x*/
      {

	x = y;
	y = y->parent;
      }
    return y;
  }
}

/*return the first node (in sorted order) which is to the left of this node
 */
treeNode* TreeNodePredecessor(treeNode* node)
{
  if(node == NULL) return NULL;
  if(node->left != NULL)
    return TreeNodeMaximum(node->left);
  else{ /*node->left is NULL*/
    /*find the first left-ancestor*/
    treeNode *y = node->parent;
    treeNode *x = node;
    while(y != NULL && x == y->left) /*if y is a right parent of x*/
      {
	x = y;
	y = y->parent;
      }
    return y;
  }
}