glsurfeval.cc

winNT技术操作系统,国外开放的原代码和LIUX一样

/*
** 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.
*/

/*
 * glsurfeval.c++
 *
 */

/* Polynomial Evaluator Interface */
#include "gluos.h"
#include <stdio.h>
#include "glimports.h"
#include "glrenderer.h"
#include "glsurfeval.h"
#include "nurbsconsts.h"
#include "bezierPatchMesh.h"


//extern int surfcount;
//int surfcount=0;

/*#define USE_INTERNAL_EVAL*/ //use internal evaluator

/*whether do evaluation or not*/
/*#define NO_EVALUATION*/

//#define USE_LOD //for LOD test, have to turn on USE_LOD in insurfeval.c++ too

/*for statistics*/
//#define STATISTICS
#ifdef STATISTICS
static int STAT_num_of_triangles=0;
static int STAT_num_of_eval_vertices=0;
static int STAT_num_of_quad_strips=0;
#endif

/*for output triangles*/
/*#define OUTPUT_TRIANGLES*/


/*#define FOR_CHRIS*/
#ifdef FOR_CHRIS
extern "C"  {  void                evalUStripExt(int n_upper, REAL v_upper, REAL* upper_val,
				   int n_lower, REAL v_lower, REAL* lower_val);}

extern "C" {   void                evalVStripExt(int n_left, REAL u_left, REAL* left_val,
				   int n_right, REAL u_right, REAL* right_val);
	     }
#endif


/**************begin for LOD_eval_list***********/
void OpenGLSurfaceEvaluator::LOD_eval_list(int level)
{
  if(level == 0)
    LOD_eval_level = 1;
  else if(level == 1)
    LOD_eval_level = 2;
  else if(level == 2)
    LOD_eval_level = 4;
  else
    LOD_eval_level = 8;

  inBPMListEvalEM(global_bpm);
}


OpenGLSurfaceEvaluator::OpenGLSurfaceEvaluator()
{
    int i;

    for (i=0; i<VERTEX_CACHE_SIZE; i++) {
	vertexCache[i] = new StoredVertex;
    }
    tmeshing = 0;
    which = 0;
    vcount = 0;

    global_uorder = 0;
    global_vorder = 0;
    global_uprime = -1.0;
    global_vprime = -1.0;
    global_vprime_BV = -1.0;
    global_uprime_BU = -1.0;
    global_uorder_BU = 0;
    global_vorder_BU = 0;
    global_uorder_BV = 0;
    global_vorder_BV = 0;
    global_baseData = NULL;
        
    global_bpm = NULL;
    output_triangles = 0; //don't output triangles by default

    //no default callback functions
    beginCallBackN = NULL;
    endCallBackN = NULL;
    vertexCallBackN = NULL;
    normalCallBackN = NULL;
    colorCallBackN = NULL;
    texcoordCallBackN = NULL;
    beginCallBackData = NULL;
    endCallBackData = NULL;
    vertexCallBackData = NULL;
    normalCallBackData = NULL;
    colorCallBackData = NULL;
    texcoordCallBackData = NULL;

    userData = NULL;

    auto_normal_flag = 0;
    callback_auto_normal = 0; //default of GLU_CALLBACK_AUTO_NORMAL is 0
    vertex_flag = 0;
    normal_flag = 0;
    color_flag = 0;
    texcoord_flag = 0;

    em_vertex.uprime = -1.0;
    em_vertex.vprime = -1.0;
    em_normal.uprime = -1.0;
    em_normal.vprime = -1.0;
    em_color.uprime = -1.0;
    em_color.vprime = -1.0;
    em_texcoord.uprime = -1.0;
    em_texcoord.vprime = -1.0;

#ifdef USE_LOD
    LOD_eval_level = 1;
#endif
}

OpenGLSurfaceEvaluator::~OpenGLSurfaceEvaluator()
{
   for (int ii= 0; ii< VERTEX_CACHE_SIZE; ii++) {
      delete vertexCache[ii];
      vertexCache[ii]= 0;
   }
}

/*---------------------------------------------------------------------------
 * disable - turn off a map
 *---------------------------------------------------------------------------
 */
void
OpenGLSurfaceEvaluator::disable(long type)
{
    glDisable((GLenum) type);
}

/*---------------------------------------------------------------------------
 * enable - turn on a map
 *---------------------------------------------------------------------------
 */
void
OpenGLSurfaceEvaluator::enable(long type)
{
    glEnable((GLenum) type);
}

/*-------------------------------------------------------------------------
 * mapgrid2f - define a lattice of points with origin and offset
 *-------------------------------------------------------------------------
 */
void
OpenGLSurfaceEvaluator::mapgrid2f(long nu, REAL u0, REAL u1, long nv, REAL v0, REAL v1)
{
#ifdef USE_INTERNAL_EVAL
  inMapGrid2f((int) nu, (REAL) u0, (REAL) u1, (int) nv,
	      (REAL) v0, (REAL) v1);
#else

  if(output_triangles)  
    {
      global_grid_u0 = u0;
      global_grid_u1 = u1;
      global_grid_nu = nu;
      global_grid_v0 = v0;
      global_grid_v1 = v1;
      global_grid_nv = nv;
    }
  else
    glMapGrid2d((GLint) nu, (GLdouble) u0, (GLdouble) u1, (GLint) nv,
	    (GLdouble) v0, (GLdouble) v1);

#endif
}

void
OpenGLSurfaceEvaluator::polymode(long style)
{
  if(! output_triangles)
    {
      switch(style) {
      default:
      case N_MESHFILL:
        
	glPolygonMode((GLenum) GL_FRONT_AND_BACK, (GLenum) GL_FILL);
	break;
      case N_MESHLINE:
	glPolygonMode((GLenum) GL_FRONT_AND_BACK, (GLenum) GL_LINE);
	break;
      case N_MESHPOINT:
	glPolygonMode((GLenum) GL_FRONT_AND_BACK, (GLenum) GL_POINT);
	break;
      }
    }
}

void
OpenGLSurfaceEvaluator::bgnline(void)
{
  if(output_triangles)
    bezierPatchMeshBeginStrip(global_bpm, GL_LINE_STRIP);
  else
    glBegin((GLenum) GL_LINE_STRIP);
}

void
OpenGLSurfaceEvaluator::endline(void)
{
  if(output_triangles)
    bezierPatchMeshEndStrip(global_bpm);
  else
    glEnd();
}

void
OpenGLSurfaceEvaluator::range2f(long type, REAL *from, REAL *to)
{
}

void
OpenGLSurfaceEvaluator::domain2f(REAL ulo, REAL uhi, REAL vlo, REAL vhi)
{
}

void
OpenGLSurfaceEvaluator::bgnclosedline(void)
{
  if(output_triangles)
    bezierPatchMeshBeginStrip(global_bpm, GL_LINE_LOOP);
  else
    glBegin((GLenum) GL_LINE_LOOP);
}

void
OpenGLSurfaceEvaluator::endclosedline(void)
{
  if(output_triangles)
    bezierPatchMeshEndStrip(global_bpm);
  else
    glEnd();
}





void
OpenGLSurfaceEvaluator::bgntmesh(void)
{

    tmeshing = 1;
    which = 0;
    vcount = 0;

    if(output_triangles)
      bezierPatchMeshBeginStrip(global_bpm, GL_TRIANGLES);
    else
      glBegin((GLenum) GL_TRIANGLES);

}

void
OpenGLSurfaceEvaluator::swaptmesh(void)
{
    which = 1 - which;

}

void
OpenGLSurfaceEvaluator::endtmesh(void)
{
    tmeshing = 0;


    if(output_triangles)
      bezierPatchMeshEndStrip(global_bpm);
    else
      glEnd();
}

void
OpenGLSurfaceEvaluator::bgntfan(void)
{

  if(output_triangles)
    bezierPatchMeshBeginStrip(global_bpm, GL_TRIANGLE_FAN);
  else
    glBegin((GLenum) GL_TRIANGLE_FAN);

}
void
OpenGLSurfaceEvaluator::endtfan(void)
{
  if(output_triangles)
	bezierPatchMeshEndStrip(global_bpm);
  else
    glEnd();
}

void
OpenGLSurfaceEvaluator::evalUStrip(int n_upper, REAL v_upper, REAL* upper_val, int n_lower, REAL v_lower, REAL* lower_val)
{
#ifdef USE_INTERNAL_EVAL
  inEvalUStrip(n_upper, v_upper, upper_val,
	n_lower, v_lower, lower_val);
#else

#ifdef FOR_CHRIS
  evalUStripExt(n_upper, v_upper, upper_val,
		 n_lower, v_lower, lower_val);
  return;

#endif
  int i,j,k,l;
  REAL leftMostV[2];

  /*
   *the algorithm works by scanning from left to right.
   *leftMostV: the left most of the remaining verteces (on both upper and lower).
   *	       it could an element of upperVerts or lowerVerts.
   *i: upperVerts[i] is the first vertex to the right of leftMostV on upper line
   *j: lowerVerts[j] is the first vertex to the right of leftMostV on lower line
   */

  /*initialize i,j,and leftMostV
   */
  if(upper_val[0] <= lower_val[0])
    {
      i=1;
      j=0;

      leftMostV[0] = upper_val[0];
      leftMostV[1] = v_upper;
    }
  else
    {
      i=0;
      j=1;

      leftMostV[0] = lower_val[0];
      leftMostV[1] = v_lower;

    }

  /*the main loop.
   *the invariance is that:
   *at the beginning of each loop, the meaning of i,j,and leftMostV are
   *maintained
   */
  while(1)
    {
      if(i >= n_upper) /*case1: no more in upper*/
	{
	  if(j<n_lower-1) /*at least two vertices in lower*/
	    {
	      bgntfan();
	      coord2f(leftMostV[0], leftMostV[1]);
//	      glNormal3fv(leftMostNormal);
//		glVertex3fv(leftMostXYZ);

	      while(j<n_lower){
		coord2f(lower_val[j], v_lower);
//		glNormal3fv(lowerNormal[j]);
//		glVertex3fv(lowerXYZ[j]);
		j++;

	      }
	      endtfan();
	    }
	  break; /*exit the main loop*/
	}
      else if(j>= n_lower) /*case2: no more in lower*/
	{
	  if(i<n_upper-1) /*at least two vertices in upper*/
	    {
	      bgntfan();
	      coord2f(leftMostV[0], leftMostV[1]);
//	      glNormal3fv(leftMostNormal);
//	      glVertex3fv(leftMostXYZ);
        
	      for(k=n_upper-1; k>=i; k--) /*reverse order for two-side lighting*/
		{
		  coord2f(upper_val[k], v_upper);
//		  glNormal3fv(upperNormal[k]);
//		  glVertex3fv(upperXYZ[k]);
		}

	      endtfan();
	    }