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Diffstat (limited to 'trunk/glagen/3d/triangle_gl.cc')
| -rw-r--r-- | trunk/glagen/3d/triangle_gl.cc | 180 |
1 files changed, 180 insertions, 0 deletions
diff --git a/trunk/glagen/3d/triangle_gl.cc b/trunk/glagen/3d/triangle_gl.cc new file mode 100644 index 0000000..173db4f --- /dev/null +++ b/trunk/glagen/3d/triangle_gl.cc @@ -0,0 +1,180 @@ +//============================================================================= +// +// Glagen : a planet sized landscape generator +// Copyright (C) 2002 Julien Guertault, Hugues Hiegel, Meng-Tih Lam +// +// This program 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. +// +// This program 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 this program; if not, write to the Free Software +// Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. +// +//============================================================================= +// +// Glagen : GPL LAndscape GENerator +// +// triangle.cc for Glagen : made by Zavie (Julien Guertault) +// +// www.glagen.org +// +//============================================================================= + +#ifndef DARWIN +# include <GL/gl.h> +# include <GL/glu.h> +#else +# include <gl.h> +# include <glu.h> +#endif + +#include "data_glagen.hh" +#include "dot.hh" +#include "triangle.hh" + +// +// Manage the T-case (when the has a 4th point) +// +bool Triangle :: T_case (const unsigned int id) +{ + Dot *middle; + Triangle *child1; + Triangle *child2; + + // Is there a triangle on this side ? + if (_neighbor_ab != NULL) + + // Then is it split ? + if (_neighbor_ab->Is_split ()) + { + // Find the dangling vertex + child1 = _neighbor_ab->Child (_a); + child2 = _neighbor_ab->Child (_b); + if (child1->B () == child2->C ()) + middle = child1->B (); + else + middle = child1->C (); + + // Display two triangles instead of just one + glBegin (GL_TRIANGLES); + _b->Display (id); + _c->Display (id); + middle->Display (id); + _c->Display (id); + _a->Display (id); + middle->Display (id); + glEnd (); + + // The T case is fixed + return true; + } + if (_neighbor_bc != NULL) + if (_neighbor_bc->Is_split ()) + { + child1 = _neighbor_bc->Child (_b); + child2 = _neighbor_bc->Child (_c); + if (child1->B () == child2->C ()) + middle = child1->B (); + else + middle = child1->C (); + glBegin (GL_TRIANGLES); + _a->Display (id); + _b->Display (id); + middle->Display (id); + _c->Display (id); + _a->Display (id); + middle->Display (id); + glEnd (); + return true; + } + if (_neighbor_ca != NULL) + if (_neighbor_ca->Is_split ()) + { + child1 = _neighbor_ca->Child (_c); + child2 = _neighbor_ca->Child (_a); + if (child1->B () == child2->C ()) + middle = child1->B (); + else + middle = child1->C (); + glBegin (GL_TRIANGLES); + _b->Display (id); + _c->Display (id); + middle->Display (id); + _a->Display (id); + _b->Display (id); + middle->Display (id); + glEnd (); + return true; + } + // In fact there's no T-case for this triangle + return false; +} + +// +// Display the faces included in the triangle (general case) +// +void Triangle :: Display (const unsigned int id) +{ + // Test if this triangle has been visited yet + if (step == glagen.step) + return; + step = glagen.step; + + if (glagen.display_all == true || _visible == true) + { + // If the triangle has childs, we visit them instead + if (_child_center != NULL) + { + _child_a->Display (id); + _child_b->Display (id); + _child_c->Display (id); + _child_center->Display (id); + } + else + { + // T-case managment + if (false == T_case (id)) + { + if (glagen.display_normal == true) + { + float x = (_a->x () + _b->x () + _c->x ()) / 3; + float y = (_a->y () + _b->y () + _c->y ()) / 3; + float z = (_a->z () + _b->z () + _c->z ()) / 3; + + // Display the normal vector + if (glagen.light) + glDisable(GL_LIGHTING); + glBegin (GL_LINES); + glColor3f(1.0, 0.2, 0.0); + glVertex3f(x, y, z); + glVertex3f(x + _normal_real.X () / 100, + y + _normal_real.Y () / 100, + z + _normal_real.Z () / 100); + glEnd (); + if (glagen.light) + glEnable(GL_LIGHTING); + } + // Could it be more simple ? + glBegin (GL_TRIANGLES); + _a->Display (id); + _b->Display (id); + _c->Display (id); + glEnd (); + } + } + } + // Recursive call at the top of the three + if (NULL == Father ()) + { + _neighbor_ab->Display (id); + _neighbor_bc->Display (id); + _neighbor_ca->Display (id); + } +} |