diff options
author | Norbert Preining <norbert@preining.info> | 2019-09-02 13:46:59 +0900 |
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committer | Norbert Preining <norbert@preining.info> | 2019-09-02 13:46:59 +0900 |
commit | e0c6872cf40896c7be36b11dcc744620f10adf1d (patch) | |
tree | 60335e10d2f4354b0674ec22d7b53f0f8abee672 /graphics/epix/clipping.cc |
Initial commit
Diffstat (limited to 'graphics/epix/clipping.cc')
-rw-r--r-- | graphics/epix/clipping.cc | 136 |
1 files changed, 136 insertions, 0 deletions
diff --git a/graphics/epix/clipping.cc b/graphics/epix/clipping.cc new file mode 100644 index 0000000000..8da785d2f5 --- /dev/null +++ b/graphics/epix/clipping.cc @@ -0,0 +1,136 @@ +/* + * clipping.cc -- Implementation of ePiX's current drawing state + * + * This file is part of ePiX, a C++ library for creating high-quality + * figures in LaTeX + * + * Version 1.1.13 + * Last Change: August 23, 2007 + */ + +/* + * Copyright (C) 2001, 2002, 2003, 2004, 2005, 2006, 2007 + * Andrew D. Hwang <rot 13 nujnat at zngupf dot ubylpebff dot rqh> + * Department of Mathematics and Computer Science + * College of the Holy Cross + * Worcester, MA, 01610-2395, USA + */ + +/* + * ePiX is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * ePiX is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY + * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public + * License for more details. + * + * You should have received a copy of the GNU General Public License + * along with ePiX; if not, write to the Free Software Foundation, Inc., + * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + */ +#include <list> + +#include "constants.h" +#include "triples.h" +#include "functions.h" +#include "clipping.h" + +namespace ePiX { + + typedef std::list<halfspace>::const_iterator Hp; + static const double INF(EPIX_INFTY); + + clip_state::clip_state(const P& arg1, const P& arg2) + { + double min1(min(arg1.x1(), arg2.x1())), max1(max(arg1.x1(), arg2.x1())); + double min2(min(arg1.x2(), arg2.x2())), max2(max(arg1.x2(), arg2.x2())); + double min3(min(arg1.x3(), arg2.x3())), max3(max(arg1.x3(), arg2.x3())); + + double avg1(0.5*(min1+max1)), avg2(0.5*(min2+max2)), avg3(0.5*(min3+max3)); + + // inward-pointing faces of clip_box + m_walls.push_back(halfspace(P(max1,avg2,avg3), P(-1, 0, 0))); + m_walls.push_back(halfspace(P(min1,avg2,avg3), P( 1, 0, 0))); + + m_walls.push_back(halfspace(P(avg1,max2,avg3), P( 0,-1, 0))); + m_walls.push_back(halfspace(P(avg1,min2,avg3), P( 0, 1, 0))); + + m_walls.push_back(halfspace(P(avg1,avg2,max3), P( 0, 0,-1))); + m_walls.push_back(halfspace(P(avg1,avg2,min3), P( 0, 0, 1))); + } + + clip_state::clip_state() + { + m_walls.push_back(halfspace(P( INF, 0, 0), P(-1, 0, 0))); + m_walls.push_back(halfspace(P(-INF, 0, 0), P( 1, 0, 0))); + + m_walls.push_back(halfspace(P( 0, INF, 0), P( 0,-1, 0))); + m_walls.push_back(halfspace(P( 0,-INF, 0), P( 0, 1, 0))); + + m_walls.push_back(halfspace(P( 0, 0, INF), P( 0, 0,-1))); + m_walls.push_back(halfspace(P( 0, 0,-INF), P( 0, 0, 1))); + } + + + clip_state& clip_state::add_face(const P& loc, const P& perp) + { + if (EPIX_EPSILON < norm(perp)) + m_extras.push_back(halfspace(loc, perp)); + + return *this; + } + + + clip_state& clip_state::clear_extras() + { + m_extras.clear(); + + return *this; + } + + + bool clip_state::clips(const P& arg) const + { + for (Hp p=m_walls.begin(); p != m_walls.end(); ++p) + if ( (*p).clips(arg) ) + return true; + + for (Hp p=m_extras.begin(); p != m_extras.end(); ++p) + if ( (*p).clips(arg) ) + return true; + + return false; + } + + // return reference to clipped argument + std::list<edge3d>& clip_state::clip_path(std::list<edge3d>& L) const + { + for (Hp p=m_walls.begin(); p != m_walls.end(); ++p) + (*p).clip_path(L); + + for (Hp p=m_extras.begin(); p != m_extras.end(); ++p) + (*p).clip_path(L); + + return L; + } + + std::list<edge3d>& clip_state::clip_loop(std::list<edge3d>& L) const + { + for (Hp p=m_walls.begin(); p != m_walls.end(); ++p) + (*p).clip_loop(L); + + for (Hp p=m_extras.begin(); p != m_extras.end(); ++p) + (*p).clip_loop(L); + + return L; + } + + clip_state& the_clip_box() + { + static clip_state* the_clip_state(new clip_state()); + return *the_clip_state; + } +} // end of namespace |