*
* 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)
**************************************************************************/
-#include <malloc.h>
+#ifndef __CYGWIN32__
+# include <malloc.h>
+#endif
+
+#ifdef WIN32
+# include <windows.h>
+#endif
+
#include <stdio.h>
#include <stdlib.h> /* atof(), atoi() */
#include <string.h>
+#include <GL/glut.h>
+
+#include "../constants.h"
+#include "../types.h"
+#include "../Math/fg_geodesy.h"
+#include "../Math/fg_random.h"
+#include "../Math/mat3.h"
+#include "../Math/polar.h"
+
#include "mesh.h"
#include "common.h"
+#include "scenery.h"
+
+
+/* Temporary hack until we get the scenery management system running */
+extern GLint mesh_hack;
+extern struct MESH eg;
+
+/* initialize the non-array mesh values */
+void mesh_init(struct MESH *m) {
+ m->originx = 0.0;
+ m->originy = 0.0;
+
+ m->rows = 0;
+ m->cols = 0;
+
+ m->row_step = 0.0;
+ m->col_step = 0.0;
+
+ m->cur_row = 0;
+ m->cur_col = 0;
+ m->do_data = 0;
+}
/* return a pointer to a new mesh structure (no data array allocated yet) */
-struct mesh *(new_mesh)() {
- struct mesh *mesh_ptr;
+struct MESH *(new_mesh)() {
+ struct MESH *mesh_ptr;
- mesh_ptr = (struct mesh *)malloc(sizeof(struct mesh));
+ mesh_ptr = (struct MESH *)malloc(sizeof(struct MESH));
if ( mesh_ptr == 0 ) {
printf("Virtual memory exceeded\n");
/* set the option name in the mesh data structure */
-void mesh_set_option_name(struct mesh *m, char *name) {
+void mesh_set_option_name(struct MESH *m, char *name) {
if ( strlen(name) < MAX_IDENT_LEN ) {
strcpy(m->option_name, name);
} else {
strncpy(m->option_name, name, MAX_IDENT_LEN - 1);
m->option_name[MAX_IDENT_LEN - 1] = '\0';
}
+ if ( strcmp(m->option_name, "do_data") == 0 ) {
+ m->do_data = 1;
+ } else {
+ m->do_data = 0;
+ }
}
+
/* set an option value in the mesh data structure */
-void mesh_set_option_value(struct mesh *m, char *value) {
- printf("Setting %s to %s\n", m->option_name, value);
+void mesh_set_option_value(struct MESH *m, char *value) {
+ /* printf("Setting %s to %s\n", m->option_name, value); */
- if ( strcmp(m->option_name, "origin_lat") == 0 ) {
- m->originx = atof(value);
+ if ( m->do_data ) {
+ /* mesh data is a pseudo 2d array */
+ /* printf("Setting mesh_data[%d][%d] to %s\n", m->cur_row, m->cur_col,
+ value); */
+ m->mesh_data[m->cur_row * m->cols + m->cur_col] = atof(value);
+ m->cur_col++;
+ if ( m->cur_col >= m->cols ) {
+ m->cur_col = 0;
+ m->cur_row++;
+ if ( m->cur_row > m->rows ) {
+ m->do_data = 0;
+ }
+ }
} else if ( strcmp(m->option_name, "origin_lon") == 0 ) {
+ m->originx = atof(value);
+ } else if ( strcmp(m->option_name, "origin_lat") == 0 ) {
m->originy = atof(value);
} else if ( strcmp(m->option_name, "rows") == 0 ) {
m->rows = atoi(value);
}
+/* do whatever needs to be done with the mesh now that it's been
+ loaded, such as generating the OpenGL call list. */
+void mesh_do_it(struct MESH *m) {
+ mesh_hack = mesh_to_OpenGL(m);
+}
+
+
+/* return the current altitude based on mesh data. We should rewrite
+ * this to interpolate exact values, but for now this is good enough */
+double mesh_altitude(double lon, double lat) {
+ /* we expect incoming (lon,lat) to be in arcsec for now */
+
+ double xlocal, ylocal, dx, dy, zA, zB, elev;
+ int x1, y1, z1, x2, y2, z2, x3, y3, z3;
+ int xindex, yindex;
+ int skip;
+
+ skip = scenery.terrain_skip;
+ /* determine if we are in the lower triangle or the upper triangle
+ ______
+ | /|
+ | / |
+ | / |
+ |/ |
+ ------
+
+ then calculate our end points
+ */
+
+ xlocal = (lon - eg.originx) / eg.col_step;
+ ylocal = (lat - eg.originy) / eg.row_step;
+
+ xindex = (int)(xlocal / skip) * skip;
+ yindex = (int)(ylocal / skip) * skip;
+
+ if ( (xindex < 0) || (xindex + skip >= eg.cols) ||
+ (yindex < 0) || (yindex + skip >= eg.rows) ) {
+ return(-9999);
+ }
+
+ dx = xlocal - xindex;
+ dy = ylocal - yindex;
+
+ if ( dx > dy ) {
+ /* lower triangle */
+ /* printf(" Lower triangle\n"); */
+
+ x1 = xindex;
+ y1 = yindex;
+ z1 = eg.mesh_data[y1 * eg.cols + x1];
+
+ x2 = xindex + skip;
+ y2 = yindex;
+ z2 = eg.mesh_data[y2 * eg.cols + x2];
+
+ x3 = xindex + skip;
+ y3 = yindex + skip;
+ z3 = eg.mesh_data[y3 * eg.cols + x3];
+
+ /* printf(" dx = %.2f dy = %.2f\n", dx, dy);
+ printf(" (x1,y1,z1) = (%d,%d,%d)\n", x1, y1, z1);
+ printf(" (x2,y2,z2) = (%d,%d,%d)\n", x2, y2, z2);
+ printf(" (x3,y3,z3) = (%d,%d,%d)\n", x3, y3, z3); */
+
+ zA = dx * (z2 - z1) / skip + z1;
+ zB = dx * (z3 - z1) / skip + z1;
+
+ /* printf(" zA = %.2f zB = %.2f\n", zA, zB); */
+
+ if ( dx > EPSILON ) {
+ elev = dy * (zB - zA) / dx + zA;
+ } else {
+ elev = zA;
+ }
+ } else {
+ /* upper triangle */
+ /* printf(" Upper triangle\n"); */
+
+ x1 = xindex;
+ y1 = yindex;
+ z1 = eg.mesh_data[y1 * eg.cols + x1];
+
+ x2 = xindex;
+ y2 = yindex + skip;
+ z2 = eg.mesh_data[y2 * eg.cols + x2];
+
+ x3 = xindex + skip;
+ y3 = yindex + skip;
+ z3 = eg.mesh_data[y3 * eg.cols + x3];
+
+ /* printf(" dx = %.2f dy = %.2f\n", dx, dy);
+ printf(" (x1,y1,z1) = (%d,%d,%d)\n", x1, y1, z1);
+ printf(" (x2,y2,z2) = (%d,%d,%d)\n", x2, y2, z2);
+ printf(" (x3,y3,z3) = (%d,%d,%d)\n", x3, y3, z3); */
+
+ zA = dy * (z2 - z1) / skip + z1;
+ zB = dy * (z3 - z1) / skip + z1;
+
+ /* printf(" zA = %.2f zB = %.2f\n", zA, zB );
+ printf(" xB - xA = %.2f\n", eg.col_step * dy / eg.row_step); */
+
+ if ( dy > EPSILON ) {
+ elev = dx * (zB - zA) / dy + zA;
+ } else {
+ elev = zA;
+ }
+ }
+
+ return(elev);
+}
+
+
+/* walk through mesh and make opengl calls */
+GLint mesh_to_OpenGL(struct MESH *m) {
+ GLint mesh;
+ /* static GLfloat color[4] = { 0.5, 0.4, 0.25, 1.0 }; */ /* dark desert */
+ static GLfloat color[4] = { 0.5, 0.5, 0.25, 1.0 };
+ double centerx, centery;
+ double randx, randy;
+
+ float x1, y1, x2, y2, z11, z12, z21, z22;
+ struct fgCartesianPoint p11, p12, p21, p22, c;
+ double gc_lon, gc_lat, sl_radius;
+
+ MAT3vec v1, v2, normal;
+ int i, j, istep, jstep, iend, jend;
+ float temp;
+
+ printf("In mesh2GL(), generating GL call list.\n");
+
+ /* Detail level. This is how big a step we take as we walk
+ * through the DEM data set. This value is initialized in
+ * .../Scenery/scenery.c:fgSceneryInit() */
+ istep = jstep = scenery.terrain_skip ;
+
+ centerx = m->originx + (m->rows * m->row_step) / 2.0;
+ centery = m->originy + (m->cols * m->col_step) / 2.0;
+ fgGeodToGeoc(centery*ARCSEC_TO_RAD, 0, &sl_radius, &gc_lat);
+ c = fgPolarToCart(centerx*ARCSEC_TO_RAD, gc_lat, sl_radius);
+ scenery.center = c;
+
+ mesh = glGenLists(1);
+ glNewList(mesh, GL_COMPILE);
+
+ /* glMaterialfv( GL_FRONT, GL_AMBIENT_AND_DIFFUSE, color ); */
+ glColor3fv(color);
+
+ 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 = m->mesh_data[i * m->cols + j ];
+ z12 = m->mesh_data[(i+istep) * m->cols + j ];
+ z21 = m->mesh_data[i * m->cols + (j+jstep)];
+ z22 = m->mesh_data[(i+istep) * m->cols + (j+jstep)];
+
+ /* printf("A geodetic point is (%.2f, %.2f, %.2f)\n",
+ x1, y1, z11); */
+ gc_lon = x1*ARCSEC_TO_RAD;
+ fgGeodToGeoc(y1*ARCSEC_TO_RAD, z11, &sl_radius, &gc_lat);
+ /* printf("A geocentric point is (%.2f, %.2f, %.2f)\n", gc_lon,
+ gc_lat, sl_radius+z11); */
+ p11 = fgPolarToCart(gc_lon, gc_lat, sl_radius+z11);
+ /* printf("A cart point is (%.8f, %.8f, %.8f)\n",
+ p11.x, p11.y, p11.z); */
+
+ gc_lon = x1*ARCSEC_TO_RAD;
+ fgGeodToGeoc(y2*ARCSEC_TO_RAD, z12, &sl_radius, &gc_lat);
+ p12 = fgPolarToCart(gc_lon, gc_lat, sl_radius+z12);
+
+ gc_lon = x2*ARCSEC_TO_RAD;
+ fgGeodToGeoc(y1*ARCSEC_TO_RAD, z21, &sl_radius, &gc_lat);
+ p21 = fgPolarToCart(gc_lon, gc_lat, sl_radius+z21);
+
+ gc_lon = x2*ARCSEC_TO_RAD;
+ fgGeodToGeoc(y2*ARCSEC_TO_RAD, z22, &sl_radius, &gc_lat);
+ p22 = fgPolarToCart(gc_lon, gc_lat, sl_radius+z22);
+
+ v1[0] = p22.y - p11.y; v1[1] = p22.z - p11.z; v1[2] = z22 - z11;
+ v2[0] = p12.y - p11.y; v2[1] = p12.z - p11.z; v2[2] = z12 - z11;
+ MAT3cross_product(normal, v1, v2);
+ MAT3_NORMALIZE_VEC(normal,temp);
+ glNormal3d(normal[0], normal[1], normal[2]);
+ /* printf("normal 1 = (%.2f %.2f %.2f\n", normal[0], normal[1],
+ normal[2]); */
+
+ if ( j == 0 ) {
+ /* first time through */
+ glVertex3d(p12.x - c.x, p12.y - c.y, p12.z - c.z);
+ glVertex3d(p11.x - c.x, p11.y - c.y, p11.z - c.z);
+ }
+
+ glVertex3d(p22.x - c.x, p22.y - c.y, p22.z - c.z);
+
+ v2[0] = p21.y - p11.y; v2[1] = p21.z - p11.z; v2[2] = z21 - z11;
+ MAT3cross_product(normal, v2, v1);
+ MAT3_NORMALIZE_VEC(normal,temp);
+ glNormal3d(normal[0], normal[1], normal[2]);
+ /* printf("normal 2 = (%.2f %.2f %.2f\n", normal[0], normal[1],
+ normal[2]); */
+
+ glVertex3d(p21.x - c.x, p21.y - c.y, p21.z - c.z);
+
+ x1 += m->row_step * jstep;
+ x2 += m->row_step * jstep;
+ }
+ glEnd();
+
+ y1 += m->col_step * istep;
+ y2 += m->col_step * istep;
+ }
+
+ /* this will go, it's only here for testing/debugging */
+
+ for ( i = 0; i < 200; i++ ) {
+ randx = fg_random() * 3600.0;
+ randy = fg_random() * 3600.0;
+
+ /* mesh_make_test_object(m->originx + randx, m->originy + randy); */
+ }
+
+ glEndList();
+
+ return(mesh);
+}
+
+
/* $Log$
-/* Revision 1.2 1997/05/19 18:20:50 curt
-/* Slight change to origin key words.
+/* Revision 1.21 1997/08/27 03:30:27 curt
+/* Changed naming scheme of basic shared structures.
/*
+ * Revision 1.20 1997/08/19 23:55:08 curt
+ * Worked on better simulating real lighting.
+ *
+ * Revision 1.19 1997/08/06 00:24:28 curt
+ * Working on correct real time sun lighting.
+ *
+ * Revision 1.18 1997/08/02 19:10:14 curt
+ * Incorporated mesh2GL.c into mesh.c
+ *
+ * Revision 1.17 1997/07/18 23:41:26 curt
+ * Tweaks for building with Cygnus Win32 compiler.
+ *
+ * Revision 1.16 1997/07/16 20:04:51 curt
+ * Minor tweaks to aid Win32 port.
+ *
+ * Revision 1.15 1997/07/14 16:26:04 curt
+ * Testing/playing -- placed objects randomly across the entire terrain.
+ *
+ * Revision 1.14 1997/07/12 04:01:14 curt
+ * Added #include <Windows32/Base.h> to help Win32 compiling.
+ *
+ * Revision 1.13 1997/07/12 02:27:11 curt
+ * Looking at potential scenery transformation/coordinate system problems.
+ *
+ * Revision 1.12 1997/07/11 03:23:19 curt
+ * Solved some scenery display/orientation problems. Still have a positioning
+ * (or transformation?) problem.
+ *
+ * Revision 1.11 1997/07/11 01:30:02 curt
+ * More tweaking of terrian floor.
+ *
+ * Revision 1.10 1997/07/10 04:26:38 curt
+ * We now can interpolated ground elevation for any position in the grid. We
+ * can use this to enforce a "hard" ground. We still need to enforce some
+ * bounds checking so that we don't try to lookup data points outside the
+ * grid data set.
+ *
+ * Revision 1.9 1997/07/10 02:22:10 curt
+ * Working on terrain elevation interpolation routine.
+ *
+ * Revision 1.8 1997/07/09 21:31:15 curt
+ * Working on making the ground "hard."
+ *
+ * Revision 1.7 1997/07/08 18:20:13 curt
+ * Working on establishing a hard ground.
+ *
+ * Revision 1.6 1997/06/29 21:16:49 curt
+ * More twiddling with the Scenery Management system.
+ *
+ * Revision 1.5 1997/06/22 21:44:41 curt
+ * Working on intergrating the VRML (subset) parser.
+ *
+ * Revision 1.4 1997/05/30 19:30:17 curt
+ * The LaRCsim flight model is starting to look like it is working.
+ *
+ * Revision 1.3 1997/05/23 15:40:41 curt
+ * Added GNU copyright headers.
+ *
+ * Revision 1.2 1997/05/19 18:20:50 curt
+ * Slight change to origin key words.
+ *
* Revision 1.1 1997/05/16 16:07:04 curt
* Initial revision.
*
projects / flightgear.git / blobdiff