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/*
** 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.
*/
/*
* backend.c++
*
*/
/* Bezier surface backend
- interprets display mode (wireframe,shaded,...)
*/
#include <stdio.h>
#include "glimports.h"
#include "mystdio.h"
#include "backend.h"
#include "basiccrveval.h"
#include "basicsurfeval.h"
#include "nurbsconsts.h"
#define NOWIREFRAME
/*-------------------------------------------------------------------------
* bgnsurf - preamble to surface definition and evaluations
*-------------------------------------------------------------------------
*/
void
Backend::bgnsurf( int wiretris, int wirequads, long nuid )
{
/*#ifndef NOWIREFRAME*/ //need this for old version
wireframetris = wiretris;
wireframequads = wirequads;
/*#endif*/
/*in the spec, GLU_DISPLAY_MODE is either
* GLU_FILL
* GLU_OUTLINE_POLY
* GLU_OUTLINE_PATCH.
*In fact, GLU_FLL is has the same effect as
* set GL_FRONT_AND_BACK to be GL_FILL
* and GLU_OUTLINE_POLY is the same as set
* GL_FRONT_AND_BACK to be GL_LINE
*It is more efficient to do this once at the beginning of
*each surface than to do it for each primitive.
* The internal has more options: outline_triangle and outline_quad
*can be seperated. But since this is not in spec, and more importantly,
*this is not so useful, so we don't need to keep this option.
*/
surfaceEvaluator.bgnmap2f( nuid );
if(wiretris)
surfaceEvaluator.polymode(N_MESHLINE);
else
surfaceEvaluator.polymode(N_MESHFILL);
}
void
Backend::patch( REAL ulo, REAL uhi, REAL vlo, REAL vhi )
{
surfaceEvaluator.domain2f( ulo, uhi, vlo, vhi );
}
void
Backend::surfbbox( long type, REAL *from, REAL *to )
{
surfaceEvaluator.range2f( type, from, to );
}
/*-------------------------------------------------------------------------
* surfpts - pass a desription of a surface map
*-------------------------------------------------------------------------
*/
void
Backend::surfpts(
long type, /* geometry, color, texture, normal */
REAL *pts, /* control points */
long ustride, /* distance to next point in u direction */
long vstride, /* distance to next point in v direction */
int uorder, /* u parametric order */
int vorder, /* v parametric order */
REAL ulo, /* u lower bound */
REAL uhi, /* u upper bound */
REAL vlo, /* v lower bound */
REAL vhi ) /* v upper bound */
{
surfaceEvaluator.map2f( type,ulo,uhi,ustride,uorder,vlo,vhi,vstride,vorder,pts );
surfaceEvaluator.enable( type );
}
/*-------------------------------------------------------------------------
* surfgrid - define a lattice of points with origin and offset
*-------------------------------------------------------------------------
*/
void
Backend::surfgrid( REAL u0, REAL u1, long nu, REAL v0, REAL v1, long nv )
{
surfaceEvaluator.mapgrid2f( nu, u0, u1, nv, v0, v1 );
}
/*-------------------------------------------------------------------------
* surfmesh - evaluate a mesh of points on lattice
*-------------------------------------------------------------------------
*/
void
Backend::surfmesh( long u, long v, long n, long m )
{
#ifndef NOWIREFRAME
if( wireframequads ) {
long v0, v1;
long u0f = u, u1f = u+n;
long v0f = v, v1f = v+m;
long parity = (u & 1);
for( v0 = v0f, v1 = v0f++ ; v0<v1f; v0 = v1, v1++ ) {
surfaceEvaluator.bgnline();
for( long u = u0f; u<=u1f; u++ ) {
if( parity ) {
surfaceEvaluator.evalpoint2i( u, v0 );
surfaceEvaluator.evalpoint2i( u, v1 );
} else {
surfaceEvaluator.evalpoint2i( u, v1 );
surfaceEvaluator.evalpoint2i( u, v0 );
}
parity = 1 - parity;
}
surfaceEvaluator.endline();
}
} else {
surfaceEvaluator.mapmesh2f( N_MESHFILL, u, u+n, v, v+m );
}
#else
if( wireframequads ) {
surfaceEvaluator.mapmesh2f( N_MESHLINE, u, u+n, v, v+m );
} else {
surfaceEvaluator.mapmesh2f( N_MESHFILL, u, u+n, v, v+m );
}
#endif
}
/*-------------------------------------------------------------------------
* endsurf - postamble to surface
*-------------------------------------------------------------------------
*/
void
Backend::endsurf( void )
{
surfaceEvaluator.endmap2f();
}
/***************************************/
void
Backend::bgntfan( void )
{
surfaceEvaluator.bgntfan();
/*
if(wireframetris)
surfaceEvaluator.polymode( N_MESHLINE );
else
surfaceEvaluator.polymode( N_MESHFILL );
*/
}
void
Backend::endtfan( void )
{
surfaceEvaluator.endtfan();
}
void
Backend::bgnqstrip( void )
{
surfaceEvaluator.bgnqstrip();
/*
if(wireframequads)
surfaceEvaluator.polymode( N_MESHLINE );
else
surfaceEvaluator.polymode( N_MESHFILL );
*/
}
void
Backend::endqstrip( void )
{
surfaceEvaluator.endqstrip();
}
void
Backend::evalUStrip(int n_upper, REAL v_upper, REAL* upper_val,
int n_lower, REAL v_lower, REAL* lower_val
)
{
surfaceEvaluator.evalUStrip(n_upper, v_upper, upper_val,
n_lower, v_lower, lower_val);
}
void
Backend::evalVStrip(int n_left, REAL u_left, REAL* left_val,
int n_right, REAL u_right, REAL* right_val
)
{
surfaceEvaluator.evalVStrip(n_left, u_left, left_val,
n_right, u_right, right_val);
}
/***************************************/
/*-------------------------------------------------------------------------
* bgntmesh - preamble to a triangle mesh
*-------------------------------------------------------------------------
*/
void
Backend::bgntmesh( const char * )
{
#ifndef NOWIREFRAME
meshindex = 0; /* I think these need to be initialized to zero */
npts = 0;
if( !wireframetris ) {
surfaceEvaluator.bgntmesh();
}
#else
if( wireframetris ) {
surfaceEvaluator.bgntmesh();
surfaceEvaluator.polymode( N_MESHLINE );
} else {
surfaceEvaluator.bgntmesh();
surfaceEvaluator.polymode( N_MESHFILL );
}
#endif
}
void
Backend::tmeshvert( GridTrimVertex *v )
{
if( v->isGridVert() ) {
tmeshvert( v->g );
} else {
tmeshvert( v->t );
}
}
void
Backend::tmeshvertNOGE(TrimVertex *t)
{
// surfaceEvaluator.inDoEvalCoord2NOGE( t->param[0], t->param[1], temp, ttt);
#ifdef USE_OPTTT
surfaceEvaluator.inDoEvalCoord2NOGE( t->param[0], t->param[1], t->cache_point, t->cache_normal);
#endif
}
//opt for a line with the same u.
void
Backend::tmeshvertNOGE_BU(TrimVertex *t)
{
#ifdef USE_OPTTT
surfaceEvaluator.inDoEvalCoord2NOGE_BU( t->param[0], t->param[1], t->cache_point, t->cache_normal);
#endif
}
//opt for a line with the same v.
void
Backend::tmeshvertNOGE_BV(TrimVertex *t)
{
#ifdef USE_OPTTT
surfaceEvaluator.inDoEvalCoord2NOGE_BV( t->param[0], t->param[1], t->cache_point, t->cache_normal);
#endif
}
void
Backend::preEvaluateBU(REAL u)
{
surfaceEvaluator.inPreEvaluateBU_intfac(u);
}
void
Backend::preEvaluateBV(REAL v)
{
surfaceEvaluator.inPreEvaluateBV_intfac(v);
}
/*-------------------------------------------------------------------------
* tmeshvert - evaluate a point on a triangle mesh
*-------------------------------------------------------------------------
*/
void
Backend::tmeshvert( TrimVertex *t )
{
#ifndef NOWIREFRAME
const long nuid = t->nuid;
#endif
const REAL u = t->param[0];
const REAL v = t->param[1];
#ifndef NOWIREFRAME
npts++;
if( wireframetris ) {
if( npts >= 3 ) {
surfaceEvaluator.bgnclosedline();
if( mesh[0][2] == 0 )
surfaceEvaluator.evalcoord2f( mesh[0][3], mesh[0][0], mesh[0][1] );
else
surfaceEvaluator.evalpoint2i( (long) mesh[0][0], (long) mesh[0][1] );
if( mesh[1][2] == 0 )
surfaceEvaluator.evalcoord2f( mesh[1][3], mesh[1][0], mesh[1][1] );
else
surfaceEvaluator.evalpoint2i( (long) mesh[1][0], (long) mesh[1][1] );
surfaceEvaluator.evalcoord2f( nuid, u, v );
surfaceEvaluator.endclosedline();
}
mesh[meshindex][0] = u;
mesh[meshindex][1] = v;
mesh[meshindex][2] = 0;
mesh[meshindex][3] = nuid;
meshindex = (meshindex+1) % 2;
} else {
surfaceEvaluator.evalcoord2f( nuid, u, v );
}
#else
surfaceEvaluator.evalcoord2f( 0, u, v );
//for uninitial memory read surfaceEvaluator.evalcoord2f( nuid, u, v );
#endif
}
//the same as tmeshvert(trimvertex), for efficiency purpose
void
Backend::tmeshvert( REAL u, REAL v )
{
#ifndef NOWIREFRAME
const long nuid = 0;
npts++;
if( wireframetris ) {
if( npts >= 3 ) {
surfaceEvaluator.bgnclosedline();
if( mesh[0][2] == 0 )
surfaceEvaluator.evalcoord2f( mesh[0][3], mesh[0][0], mesh[0][1] );
else
surfaceEvaluator.evalpoint2i( (long) mesh[0][0], (long) mesh[0][1] );
if( mesh[1][2] == 0 )
surfaceEvaluator.evalcoord2f( mesh[1][3], mesh[1][0], mesh[1][1] );
else
surfaceEvaluator.evalpoint2i( (long) mesh[1][0], (long) mesh[1][1] );
surfaceEvaluator.evalcoord2f( nuid, u, v );
surfaceEvaluator.endclosedline();
}
mesh[meshindex][0] = u;
mesh[meshindex][1] = v;
mesh[meshindex][2] = 0;
mesh[meshindex][3] = nuid;
meshindex = (meshindex+1) % 2;
} else {
surfaceEvaluator.evalcoord2f( nuid, u, v );
}
#else
surfaceEvaluator.evalcoord2f( 0, u, v );
#endif
}
/*-------------------------------------------------------------------------
* tmeshvert - evaluate a grid point of a triangle mesh
*-------------------------------------------------------------------------
*/
void
Backend::tmeshvert( GridVertex *g )
{
const long u = g->gparam[0];
const long v = g->gparam[1];
#ifndef NOWIREFRAME
npts++;
if( wireframetris ) {
if( npts >= 3 ) {
surfaceEvaluator.bgnclosedline();
if( mesh[0][2] == 0 )
surfaceEvaluator.evalcoord2f( (long) mesh[0][3], mesh[0][0], mesh[0][1] );
else
surfaceEvaluator.evalpoint2i( (long) mesh[0][0], (long) mesh[0][1] );
if( mesh[1][2] == 0 )
surfaceEvaluator.evalcoord2f( (long) mesh[1][3], mesh[1][0], mesh[1][1] );
else
surfaceEvaluator.evalpoint2i( (long) mesh[1][0], (long) mesh[1][1] );
surfaceEvaluator.evalpoint2i( u, v );
surfaceEvaluator.endclosedline();
}
mesh[meshindex][0] = u;
mesh[meshindex][1] = v;
mesh[meshindex][2] = 1;
meshindex = (meshindex+1) % 2;
} else {
surfaceEvaluator.evalpoint2i( u, v );
}
#else
surfaceEvaluator.evalpoint2i( u, v );
#endif
}
/*-------------------------------------------------------------------------
* swaptmesh - perform a swap of the triangle mesh pointers
*-------------------------------------------------------------------------
*/
void
Backend::swaptmesh( void )
{
#ifndef NOWIREFRAME
if( wireframetris ) {
meshindex = 1 - meshindex;
} else {
surfaceEvaluator.swaptmesh();
}
#else
surfaceEvaluator.swaptmesh();
#endif
}
/*-------------------------------------------------------------------------
* endtmesh - postamble to triangle mesh
*-------------------------------------------------------------------------
*/
void
Backend::endtmesh( void )
{
#ifndef NOWIREFRAME
if( ! wireframetris )
surfaceEvaluator.endtmesh();
#else
surfaceEvaluator.endtmesh();
/* surfaceEvaluator.polymode( N_MESHFILL );*/
#endif
}
/*-------------------------------------------------------------------------
* bgnoutline - preamble to outlined rendering
*-------------------------------------------------------------------------
*/
void
Backend::bgnoutline( void )
{
surfaceEvaluator.bgnline();
}
/*-------------------------------------------------------------------------
* linevert - evaluate a point on an outlined contour
*-------------------------------------------------------------------------
*/
void
Backend::linevert( TrimVertex *t )
{
surfaceEvaluator.evalcoord2f( t->nuid, t->param[0], t->param[1] );
}
/*-------------------------------------------------------------------------
* linevert - evaluate a grid point of an outlined contour
*-------------------------------------------------------------------------
*/
void
Backend::linevert( GridVertex *g )
{
surfaceEvaluator.evalpoint2i( g->gparam[0], g->gparam[1] );
}
/*-------------------------------------------------------------------------
* endoutline - postamble to outlined rendering
*-------------------------------------------------------------------------
*/
void
Backend::endoutline( void )
{
surfaceEvaluator.endline();
}
/*-------------------------------------------------------------------------
* triangle - output a triangle
*-------------------------------------------------------------------------
*/
void
Backend::triangle( TrimVertex *a, TrimVertex *b, TrimVertex *c )
{
/* bgntmesh( "spittriangle" );*/
bgntfan();
tmeshvert( a );
tmeshvert( b );
tmeshvert( c );
endtfan();
/* endtmesh();*/
}
void
Backend::bgncurv( void )
{
curveEvaluator.bgnmap1f( 0 );
}
void
Backend::segment( REAL ulo, REAL uhi )
{
curveEvaluator.domain1f( ulo, uhi );
}
void
Backend::curvpts(
long type, /* geometry, color, texture, normal */
REAL *pts, /* control points */
long stride, /* distance to next point */
int order, /* parametric order */
REAL ulo, /* lower parametric bound */
REAL uhi ) /* upper parametric bound */
{
curveEvaluator.map1f( type, ulo, uhi, stride, order, pts );
curveEvaluator.enable( type );
}
void
Backend::curvgrid( REAL u0, REAL u1, long nu )
{
curveEvaluator.mapgrid1f( nu, u0, u1 );
}
void
Backend::curvmesh( long from, long n )
{
curveEvaluator.mapmesh1f( N_MESHFILL, from, from+n );
}
void
Backend::curvpt(REAL u)
{
curveEvaluator.evalcoord1f( 0, u );
}
void
Backend::bgnline( void )
{
curveEvaluator.bgnline();
}
void
Backend::endline( void )
{
curveEvaluator.endline();
}
void
Backend::endcurv( void )
{
curveEvaluator.endmap1f();
}
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