coveandtiler.cc

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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.
*/

/*
 * coveandtiler.c++
 *
 */

#include "glimports.h"
#include "myassert.h"
#include "mystdio.h"
#include "coveandtiler.h"
#include "gridvertex.h"
#include "gridtrimvertex.h"
#include "uarray.h"
#include "backend.h"


const int CoveAndTiler::MAXSTRIPSIZE = 1000;

CoveAndTiler::CoveAndTiler( Backend& b )
        : backend( b )
{ }

CoveAndTiler::~CoveAndTiler( void )
{ }

inline void
CoveAndTiler::output( GridVertex &gv )
{
    backend.tmeshvert( &gv );
}

inline void
CoveAndTiler::output( TrimVertex *tv )
{
    backend.tmeshvert( tv );
}

inline void
CoveAndTiler::output( GridTrimVertex& g )
{
    backend.tmeshvert( &g );
}

void
CoveAndTiler::coveAndTile( void )
{
    long ustart = (top.ustart >= bot.ustart) ? top.ustart : bot.ustart;
    long uend   = (top.uend <= bot.uend)     ? top.uend   : bot.uend;
    if( ustart <= uend ) {
    tile( bot.vindex, ustart, uend );
    if( top.ustart >= bot.ustart )
        coveUpperLeft();
    else
        coveLowerLeft();

    if( top.uend <= bot.uend )
        coveUpperRight();
    else
        coveLowerRight();
    } else {
    TrimVertex blv, tlv, *bl, *tl;
    GridTrimVertex bllv, tllv;
    TrimVertex *lf = left.first();
    TrimVertex *ll = left.last();
    if( lf->param[0] >= ll->param[0] ) {
        blv.param[0] = lf->param[0];
        blv.param[1] = ll->param[1];
        blv.nuid = 0; // XXX
        assert( blv.param[1] == bot.vval );
        bl = &blv;
        tl = lf;
        tllv.set( lf );
        if( ll->param[0] > uarray.uarray[top.ustart-1] ) {
        bllv.set( ll );
        assert( ll->param[0] <= uarray.uarray[bot.ustart] );
        } else {
        bllv.set( top.ustart-1, bot.vindex );
        }
        coveUpperLeftNoGrid( bl );
    } else {
        tlv.param[0] = ll->param[0];
        tlv.param[1] = lf->param[1];
        tlv.nuid = 0; // XXX
        assert( tlv.param[1] == top.vval );
        tl = &tlv;
        bl = ll;
        bllv.set( ll );
        if( lf->param[0] > uarray.uarray[bot.ustart-1] ) {
        assert( lf->param[0] <= uarray.uarray[bot.ustart] );
        tllv.set( lf );
        } else {
        tllv.set( bot.ustart-1, top.vindex );
        }
        coveLowerLeftNoGrid( tl );
    }

    TrimVertex brv, trv, *br, *tr;
    GridTrimVertex brrv, trrv;
    TrimVertex *rf = right.first();
    TrimVertex *rl = right.last();

    if( rf->param[0] <= rl->param[0] ) {
        brv.param[0] = rf->param[0];
        brv.param[1] = rl->param[1];
        brv.nuid = 0; // XXX
        assert( brv.param[1] == bot.vval );
        br = &brv;
        tr = rf;
        trrv.set( rf );
        if( rl->param[0] < uarray.uarray[top.uend+1] ) {
        assert( rl->param[0] >= uarray.uarray[top.uend] );
        brrv.set( rl );
        } else {
        brrv.set( top.uend+1, bot.vindex );
        }
        coveUpperRightNoGrid( br );
    } else {
        trv.param[0] = rl->param[0];
        trv.param[1] = rf->param[1];
        trv.nuid = 0; // XXX
        assert( trv.param[1] == top.vval );
        tr = &trv;
        br = rl;
        brrv.set( rl );
        if( rf->param[0] < uarray.uarray[bot.uend+1] ) {
        assert( rf->param[0] >= uarray.uarray[bot.uend] );
        trrv.set( rf );
        } else {
        trrv.set( bot.uend+1, top.vindex );
        }
        coveLowerRightNoGrid( tr );
    }

    backend.bgntmesh( "doit" );
    output(trrv);
    output(tllv);
    output( tr );
    output( tl );
    output( br );
    output( bl );
    output(brrv);
    output(bllv);
    backend.endtmesh();
    }
}

void
CoveAndTiler::tile( long vindex, long ustart, long uend )
{
    long numsteps = uend - ustart;

    if( numsteps == 0 ) return;

    if( numsteps > MAXSTRIPSIZE ) {
    long umid = ustart + (uend - ustart) / 2;
    tile( vindex, ustart, umid );
    tile( vindex, umid, uend );
    } else {
    backend.surfmesh( ustart, vindex-1, numsteps, 1 );
    }
}

void
CoveAndTiler::coveUpperRight( void )
{
    GridVertex tgv( top.uend, top.vindex );
    GridVertex gv( top.uend, bot.vindex );

    right.first();
    backend.bgntmesh( "coveUpperRight" );
    output( right.next() );
    output( tgv );
    backend.swaptmesh();
    output( gv );
    coveUR();
    backend.endtmesh();
}

void
CoveAndTiler::coveUpperRightNoGrid( TrimVertex* br )
{
    backend.bgntmesh( "coveUpperRight" );
    output( right.first() );
    output( right.next() );
    backend.swaptmesh();
    output( br );
    coveUR();
    backend.endtmesh();
}

void
CoveAndTiler::coveUR( )
{
    GridVertex gv( top.uend, bot.vindex );
    TrimVertex *vert = right.next();
    if( vert == NULL ) return;

    assert( vert->param[0] >= uarray.uarray[gv.gparam[0]]  );

    if( gv.nextu() >= bot.uend ) {
    for( ; vert; vert = right.next() ) {
        output( vert );
        backend.swaptmesh();
    }
    } else while( 1 ) {
    if( vert->param[0] < uarray.uarray[gv.gparam[0]]  ) {
        output( vert );
        backend.swaptmesh();
        vert = right.next();
        if( vert == NULL ) break;
    } else {
        backend.swaptmesh();
        output( gv );
        if( gv.nextu() == bot.uend ) {
        for( ; vert; vert = right.next() ) {
            output( vert );
            backend.swaptmesh();
        }
        break;
        }
    }
    }
}

void
CoveAndTiler::coveUpperLeft( void )
{
    GridVertex tgv( top.ustart, top.vindex );
    GridVertex gv( top.ustart, bot.vindex );

    left.first();
    backend.bgntmesh( "coveUpperLeft" );
    output( tgv );
    output( left.next() );
    output( gv );
    backend.swaptmesh();
    coveUL();
    backend.endtmesh();
}

void
CoveAndTiler::coveUpperLeftNoGrid( TrimVertex* bl )
{
    backend.bgntmesh( "coveUpperLeftNoGrid" );
    output( left.first() );
    output( left.next() );
    output( bl );
    backend.swaptmesh();
    coveUL();
    backend.endtmesh();
}

void
CoveAndTiler::coveUL()
{
    GridVertex gv( top.ustart, bot.vindex );
    TrimVertex *vert = left.next();
    if( vert == NULL ) return;
    assert( vert->param[0] <= uarray.uarray[gv.gparam[0]]  );

    if( gv.prevu() <= bot.ustart ) {
    for( ; vert; vert = left.next() ) {
        backend.swaptmesh();
        output( vert );
    }
    } else while( 1 ) {
    if( vert->param[0] > uarray.uarray[gv.gparam[0]]  ) {
        backend.swaptmesh();
        output( vert );
        vert = left.next();
        if( vert == NULL ) break;
    } else {
        output( gv );
        backend.swaptmesh();
        if( gv.prevu() == bot.ustart ) {
        for( ; vert; vert = left.next() ) {
            backend.swaptmesh();
            output( vert );
        }
        break;
        }
    }
    }
}

void
CoveAndTiler::coveLowerLeft( void )
{
    GridVertex bgv( bot.ustart, bot.vindex );
    GridVertex gv( bot.ustart, top.vindex );

    left.last();
    backend.bgntmesh( "coveLowerLeft" );
    output( left.prev() );
    output( bgv );
    backend.swaptmesh();
    output( gv );
    coveLL();
    backend.endtmesh();
}

void
CoveAndTiler::coveLowerLeftNoGrid( TrimVertex* tl )
{
    backend.bgntmesh( "coveLowerLeft" );
    output( left.last() );
    output( left.prev() );
    backend.swaptmesh();
    output( tl );
    coveLL( );
    backend.endtmesh();
}

void
CoveAndTiler::coveLL()
{
    GridVertex gv( bot.ustart, top.vindex );
    TrimVertex *vert = left.prev();
    if( vert == NULL ) return;
    assert( vert->param[0] <= uarray.uarray[gv.gparam[0]]  );

    if( gv.prevu() <= top.ustart ) {
    for( ; vert; vert = left.prev() ) {
        output( vert );
        backend.swaptmesh();
    }
    } else while( 1 ) {
    if( vert->param[0] > uarray.uarray[gv.gparam[0]] ){
        output( vert );
        backend.swaptmesh();
        vert = left.prev();
        if( vert == NULL ) break;
    } else {
        backend.swaptmesh();
        output( gv );
        if( gv.prevu() == top.ustart ) {
        for( ; vert; vert = left.prev() ) {
            output( vert );
            backend.swaptmesh();
        }
        break;
        }
    }
    }
}

void
CoveAndTiler::coveLowerRight( void )
{
    GridVertex bgv( bot.uend, bot.vindex );
    GridVertex gv( bot.uend, top.vindex );

    right.last();
    backend.bgntmesh( "coveLowerRight" );       
    output( bgv );
    output( right.prev() );
    output( gv );
    backend.swaptmesh();
    coveLR();
    backend.endtmesh( );
}

void
CoveAndTiler::coveLowerRightNoGrid( TrimVertex* tr )
{
    backend.bgntmesh( "coveLowerRIght" );
    output( right.last() );
    output( right.prev() );
    output( tr );
    backend.swaptmesh();
    coveLR();
    backend.endtmesh();
}

void
CoveAndTiler::coveLR( )
{
    GridVertex gv( bot.uend, top.vindex );
    TrimVertex *vert = right.prev();
    if( vert == NULL ) return;
    assert( vert->param[0] >= uarray.uarray[gv.gparam[0]]  );

    if( gv.nextu() >= top.uend ) {
    for( ; vert; vert = right.prev() ) {
        backend.swaptmesh();
        output( vert );
    }
    } else while( 1 ) {
    if( vert->param[0] < uarray.uarray[gv.gparam[0]]  ) {
        backend.swaptmesh();
        output( vert );
        vert = right.prev();
        if( vert == NULL ) break;
    } else {
        output( gv );
        backend.swaptmesh();
        if( gv.nextu() == top.uend ) {
        for( ; vert; vert = right.prev() ) {
            backend.swaptmesh();
            output( vert );
        }
        break;
        }
    }
    }
}