ReactOS  0.4.11-dev-721-g95bc44e
hull.cc
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1 /*
2 ** License Applicability. Except to the extent portions of this file are
3 ** made subject to an alternative license as permitted in the SGI Free
4 ** Software License B, Version 1.1 (the "License"), the contents of this
5 ** file are subject only to the provisions of the License. You may not use
6 ** this file except in compliance with the License. You may obtain a copy
7 ** of the License at Silicon Graphics, Inc., attn: Legal Services, 1600
8 ** Amphitheatre Parkway, Mountain View, CA 94043-1351, or at:
9 **
10 ** http://oss.sgi.com/projects/FreeB
11 **
12 ** Note that, as provided in the License, the Software is distributed on an
13 ** "AS IS" basis, with ALL EXPRESS AND IMPLIED WARRANTIES AND CONDITIONS
14 ** DISCLAIMED, INCLUDING, WITHOUT LIMITATION, ANY IMPLIED WARRANTIES AND
15 ** CONDITIONS OF MERCHANTABILITY, SATISFACTORY QUALITY, FITNESS FOR A
16 ** PARTICULAR PURPOSE, AND NON-INFRINGEMENT.
17 **
18 ** Original Code. The Original Code is: OpenGL Sample Implementation,
19 ** Version 1.2.1, released January 26, 2000, developed by Silicon Graphics,
20 ** Inc. The Original Code is Copyright (c) 1991-2000 Silicon Graphics, Inc.
21 ** Copyright in any portions created by third parties is as indicated
22 ** elsewhere herein. All Rights Reserved.
23 **
24 ** Additional Notice Provisions: The application programming interfaces
25 ** established by SGI in conjunction with the Original Code are The
26 ** OpenGL(R) Graphics System: A Specification (Version 1.2.1), released
27 ** April 1, 1999; The OpenGL(R) Graphics System Utility Library (Version
28 ** 1.3), released November 4, 1998; and OpenGL(R) Graphics with the X
29 ** Window System(R) (Version 1.3), released October 19, 1998. This software
30 ** was created using the OpenGL(R) version 1.2.1 Sample Implementation
31 ** published by SGI, but has not been independently verified as being
32 ** compliant with the OpenGL(R) version 1.2.1 Specification.
33 */
34 
35 /*
36  * hull.c++
37  *
38  */
39 
40 //#include "glimports.h"
41 //#include "myassert.h"
42 //#include "mystdio.h"
43 #include "hull.h"
44 //#include "gridvertex.h"
45 //#include "gridtrimvertex.h"
46 //#include "gridline.h"
47 //#include "trimline.h"
48 //#include "uarray.h"
49 //#include "trimregion.h"
50 
51 Hull::Hull( void )
52 {}
53 
54 Hull::~Hull( void )
55 {}
56 
57 /*----------------------------------------------------------------------
58  * Hull:init - this routine does the initialization needed before any
59  * calls to nextupper or nextlower can be made.
60  *----------------------------------------------------------------------
61  */
62 void
63 Hull::init( void )
64 {
65  TrimVertex *lfirst = left.first();
66  TrimVertex *llast = left.last();
67  if( lfirst->param[0] <= llast->param[0] ) {
68  fakeleft.init( left.first() );
69  upper.left = &fakeleft;
70  lower.left = &left;
71  } else {
72  fakeleft.init( left.last() );
73  lower.left = &fakeleft;
74  upper.left = &left;
75  }
76  upper.left->last();
77  lower.left->first();
78 
79  if( top.ustart <= top.uend ) {
80  upper.line = &top;
81  upper.index = top.ustart;
82  } else
83  upper.line = 0;
84 
85  if( bot.ustart <= bot.uend ) {
86  lower.line = &bot;
88  } else
89  lower.line = 0;
90 
91  TrimVertex *rfirst = right.first();
92  TrimVertex *rlast = right.last();
93  if( rfirst->param[0] <= rlast->param[0] ) {
94  fakeright.init( right.last() );
96  upper.right = &right;
97  } else {
98  fakeright.init( right.first() );
100  lower.right = &right;
101  }
102  upper.right->first();
103  lower.right->last();
104 }
105 
106 /*----------------------------------------------------------------------
107  * nextupper - find next vertex on upper hull of trim region.
108  * - if vertex is on trim curve, set vtop point to
109  * that vertex. if vertex is on grid, set vtop to
110  * point to temporary area and stuff coordinants into
111  * temporary vertex. Also, place grid coords in temporary
112  * grid vertex.
113  *----------------------------------------------------------------------
114  */
117 {
118  if( upper.left ) {
119  gv->set( upper.left->prev() );
120  if( gv->isTrimVert() ) return gv;
121  upper.left = 0;
122  }
123 
124  if( upper.line ) {
125  assert( upper.index <= upper.line->uend );
127  gv->set( upper.index, upper.line->vindex );
128  if( upper.index++ == upper.line->uend ) upper.line = 0;
129  return gv;
130  }
131 
132  if( upper.right ) {
133  gv->set( upper.right->next() );
134  if( gv->isTrimVert() ) return gv;
135  upper.right = 0;
136  }
137 
138  return 0;
139 }
140 
143 {
144  if( lower.left ) {
145  gv->set( lower.left->next() );
146  if( gv->isTrimVert() ) return gv;
147  lower.left = 0;
148  }
149 
150  if( lower.line ) {
152  gv->set( lower.index, lower.line->vindex );
153  if( lower.index++ == lower.line->uend ) lower.line = 0;
154  return gv;
155  }
156 
157  if( lower.right ) {
158  gv->set( lower.right->prev() );
159  if( gv->isTrimVert() ) return gv;
160  lower.right = 0;
161  }
162 
163  return 0;
164 }
165 
GridTrimVertex * nextupper(GridTrimVertex *)
Definition: hull.cc:116
Gridline * line
Definition: hull.h:57
TrimVertex * prev(void)
Definition: trimline.h:87
long uend
Definition: gridline.h:44
Gridline bot
Definition: trimregion.h:56
long ustart
Definition: gridline.h:43
void init(TrimVertex *)
Definition: trimline.cc:58
TrimVertex * first(void)
Definition: trimline.h:93
Trimline * left
Definition: hull.h:56
#define assert(x)
Definition: debug.h:53
long index
Definition: hull.h:59
Hull(void)
Definition: hull.cc:51
Side upper
Definition: hull.h:63
Trimline right
Definition: trimregion.h:54
GridTrimVertex * nextlower(GridTrimVertex *)
Definition: hull.cc:142
REAL * uarray
Definition: uarray.h:52
Side lower
Definition: hull.h:62
GLint left
Definition: glext.h:7726
GLdouble GLdouble right
Definition: glext.h:10859
Uarray uarray
Definition: trimregion.h:57
Trimline left
Definition: trimregion.h:53
void set(long, long)
void init(void)
Definition: hull.cc:63
REAL vval
Definition: gridline.h:41
TrimVertex * next(void)
Definition: trimline.h:81
REAL param[2]
Definition: trimvertex.h:45
Trimline fakeright
Definition: hull.h:65
long vindex
Definition: gridline.h:42
Gridline top
Definition: trimregion.h:55
Trimline * right
Definition: hull.h:58
GLdouble GLdouble GLdouble GLdouble top
Definition: glext.h:10859
Trimline fakeleft
Definition: hull.h:64
~Hull(void)
Definition: hull.cc:54
TrimVertex * last(void)
Definition: trimline.h:99