152 lines
4.3 KiB
C
152 lines
4.3 KiB
C
/**************************************************************************
|
|
* mesh2GL.c -- walk through a mesh data structure and make GL calls
|
|
*
|
|
* Written by Curtis Olson, started May 1997.
|
|
*
|
|
* Copyright (C) 1997 Curtis L. Olson - curt@infoplane.com
|
|
*
|
|
* 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., 675 Mass Ave, Cambridge, MA 02139, USA.
|
|
*
|
|
* $Id$
|
|
* (Log is kept at end of this file)
|
|
**************************************************************************/
|
|
|
|
|
|
#ifdef GLUT
|
|
#include <GL/glut.h>
|
|
#elif TIGER
|
|
/* assumes -I/usr/include/mesa in compile command */
|
|
#include "gltk.h"
|
|
#endif
|
|
|
|
#include "../scenery/mesh.h"
|
|
#include "mat3.h"
|
|
|
|
|
|
/* Sets the first vector to be the cross-product of the last two
|
|
vectors. */
|
|
static void mat3_cross_product(float result_vec[3], register float vec1[3],
|
|
register float vec2[3]) {
|
|
float tempvec[3];
|
|
register float *temp = tempvec;
|
|
|
|
temp[0] = vec1[1] * vec2[2] - vec1[2] * vec2[1];
|
|
temp[1] = vec1[2] * vec2[0] - vec1[0] * vec2[2];
|
|
temp[2] = vec1[0] * vec2[1] - vec1[1] * vec2[0];
|
|
|
|
MAT3_COPY_VEC(result_vec, temp);
|
|
}
|
|
|
|
|
|
/* walk through mesh and make ogl calls */
|
|
GLint mesh2GL(struct mesh *m) {
|
|
GLint mesh;
|
|
|
|
float x1, y1, x2, y2, z11, z12, z21, z22;
|
|
float v1[3], v2[3], normal[3];
|
|
int i, j, istep, jstep, iend, jend;
|
|
float temp;
|
|
|
|
istep = jstep = 5; /* Detail level 1 - 1200 ... */
|
|
|
|
mesh = glGenLists(1);
|
|
glNewList(mesh, GL_COMPILE);
|
|
|
|
iend = m->cols - 1;
|
|
jend = m->rows - 1;
|
|
|
|
y1 = m->originy;
|
|
y2 = y1 + (m->col_step * istep);
|
|
|
|
for ( i = 0; i < iend; i += istep ) {
|
|
x1 = m->originx;
|
|
x2 = x1 + (m->row_step * jstep);
|
|
|
|
glBegin(GL_TRIANGLE_STRIP);
|
|
|
|
for ( j = 0; j < jend; j += jstep ) {
|
|
z11 = 0.03 * m->mesh_data[j * m->rows + i ];
|
|
z12 = 0.03 * m->mesh_data[j * m->rows + (i+istep)];
|
|
z21 = 0.03 * m->mesh_data[(j+jstep) * m->rows + i ];
|
|
z22 = 0.03 * m->mesh_data[(j+jstep) * m->rows + (i+istep)];
|
|
|
|
v1[0] = x2 - x1; v1[1] = 0; v1[2] = z21 - z11;
|
|
v2[0] = 0; v2[1] = y2 - y1; v2[2] = z12 - z11;
|
|
mat3_cross_product(normal, v1, v2);
|
|
MAT3_NORMALIZE_VEC(normal,temp);
|
|
glNormal3fv(normal);
|
|
|
|
if ( j == 0 ) {
|
|
/* first time through */
|
|
glVertex3f(x1, y1, z11);
|
|
glVertex3f(x1, y2, z12);
|
|
}
|
|
|
|
glVertex3f(x2, y1, z21);
|
|
|
|
v1[0] = x2 - x1; v1[1] = y1 - y2; v1[2] = z21 - z12;
|
|
v2[0] = x2 - x1; v2[1] = 0; v2[2] = z22 - z12;
|
|
mat3_cross_product(normal, v1, v2);
|
|
MAT3_NORMALIZE_VEC(normal,temp);
|
|
glNormal3fv(normal);
|
|
glVertex3f(x2, y2, z22);
|
|
|
|
x1 = x2;
|
|
x2 = x1 + (m->row_step * jstep);
|
|
}
|
|
glEnd();
|
|
|
|
y1 = y2;
|
|
y2 = y1 + (m->col_step * istep);
|
|
}
|
|
|
|
glEndList();
|
|
|
|
return(mesh);
|
|
}
|
|
|
|
|
|
/* $Log$
|
|
/* Revision 1.6 1997/05/27 17:44:32 curt
|
|
/* Renamed & rearranged variables and routines. Added some initial simple
|
|
/* timer/alarm routines so the flight model can be updated on a regular interval.
|
|
/*
|
|
* Revision 1.5 1997/05/24 01:45:32 curt
|
|
* Fixed surface normals for triangle mesh.
|
|
*
|
|
* Revision 1.4 1997/05/23 20:05:24 curt
|
|
* First stab at using GL_TRIANGLE_STRIP's instead of GL_POLYGONS (to conserve
|
|
* memory)
|
|
*
|
|
* Revision 1.3 1997/05/23 15:40:26 curt
|
|
* Added GNU copyright headers.
|
|
* Fog now works!
|
|
*
|
|
* Revision 1.2 1997/05/23 00:35:13 curt
|
|
* Trying to get fog to work ...
|
|
*
|
|
* Revision 1.1 1997/05/21 15:57:52 curt
|
|
* Renamed due to added GLUT support.
|
|
*
|
|
* Revision 1.3 1997/05/19 18:22:42 curt
|
|
* Parameter tweaking ... starting to stub in fog support.
|
|
*
|
|
* Revision 1.2 1997/05/17 00:17:35 curt
|
|
* Trying to stub in support for standard OpenGL.
|
|
*
|
|
* Revision 1.1 1997/05/16 16:05:52 curt
|
|
* Initial revision.
|
|
*
|
|
*/
|