src/glu/sgi/libnurbs/nurbtess/gridWrap.h

   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 */
  37
  38 #ifndef _GRIDWRAP_H
  39 #define _GRIDWRAP_H
  40
  41 #include <stdio.h>
  42 #include "definitions.h"
  43
  44 #include "primitiveStream.h"
  45 #include "zlassert.h"
  46
  47 class gridWrap{
  48   Int n_ulines;
  49   Int n_vlines;
  50   Real u_min, u_max;
  51   Real v_min, v_max;
  52
  53   /*cache the coordinate values for efficiency.
  54    *these are redundant information when
  55    *the grid is uniform.
  56    */
  57   Real* u_values; /*size is n_ulines*/
  58   Real* v_values; /*size is n_vlines*/
  59
  60   Int is_uniform;
  61
  62 public:
  63   //uniform grid constructor
  64   gridWrap(Int nUlines, Int nVlines,
  65            Real uMin, Real uMax,
  66            Real vMin, Real vMax
  67            );
  68
  69   //nonuniform grid constructor.
  70   gridWrap(Int nUlines, Real *uvals,
  71            Int nVlines, Real *vvlas
  72            );
  73   ~gridWrap();
  74
  75   void print();
  76   Int get_n_ulines() {return n_ulines;}
  77   Int get_n_vlines() {return n_vlines;}
  78   Real get_u_min() {return u_min;}
  79   Real get_u_max() {return u_max;}
  80   Real get_v_min() {return v_min;}
  81   Real get_v_max() {return v_max;}
  82
  83   Real get_u_value(Int i)
  84     {
  85       assert(i<n_ulines);
  86       /*if(i>=n_ulines){printf("ERROR, n_ulines=%i,i=%i\n",n_ulines,i);exit(0);}*/
  87       return u_values[i];}
  88   Real get_v_value(Int j) {return v_values[j];}
  89
  90   Real* get_u_values() {return u_values;}
  91   Real* get_v_values() {return v_values;}
  92
  93   void outputFanWithPoint(Int v, Int uleft, Int uright,
  94                           Real vert[2], primStream* pStream);
  95
  96   void draw();
  97
  98   Int isUniform() {return is_uniform;}
  99 };
 100
 101 class gridBoundaryChain{
 102   gridWrap* grid;
 103   Int firstVlineIndex;
 104   Int nVlines;
 105   Int* ulineIndices; /*each v line has a boundary*/
 106   Int* innerIndices; /*the segment of the vertical gridline from */
 107                      /*(innerIndices[i], i) to (innerIndices[i+1], i-1) */
 108                      /*is inside the polygon: i=1,...,nVlines-1*/
 109
 110   Real2* vertices; /*one grid point at each grid V-line, cached for efficiency*/
 111
 112 public:
 113   gridBoundaryChain(gridWrap* gr, Int first_vline_index, Int n_vlines, Int* uline_indices, Int* inner_indices);
 114
 115   ~gridBoundaryChain()
 116     {
 117       free(innerIndices);
 118       free(ulineIndices);
 119       free(vertices);
 120     }
 121
 122   /*i indexes the vlines in this chain.
 123    */
 124   Int getVlineIndex(Int i) {return firstVlineIndex-i;}
 125   Int getUlineIndex(Int i) {return ulineIndices[i];}
 126   Real get_u_value(Int i) {return vertices[i][0];}
 127   Real get_v_value(Int i) {return vertices[i][1];}
 128   Int get_nVlines() {return nVlines;}
 129   Int getInnerIndex(Int i) {return innerIndices[i];}
 130   Real getInner_u_value(Int i) {return grid->get_u_value(innerIndices[i]);}
 131
 132   Real* get_vertex(Int i) {return vertices[i];}
 133   gridWrap* getGrid() {return grid;}
 134   void leftEndFan(Int i, primStream* pStream);
 135   void rightEndFan(Int i, primStream* pStream);
 136
 137   Int lookfor(Real v, Int i1, Int i2); //find i in [i1,i2] so that  vertices[i][1]>= v > vertices[i+1][1]
 138   void draw();
 139   void drawInner();
 140 };
 141
 142 #endif