2 // views.cxx -- data structures and routines for managing and view parameters.
4 // Written by Curtis Olson, started August 1997.
6 // Copyright (C) 1997 Curtis L. Olson - curt@infoplane.com
8 // This program is free software; you can redistribute it and/or
9 // modify it under the terms of the GNU General Public License as
10 // published by the Free Software Foundation; either version 2 of the
11 // License, or (at your option) any later version.
13 // This program is distributed in the hope that it will be useful, but
14 // WITHOUT ANY WARRANTY; without even the implied warranty of
15 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 // General Public License for more details.
18 // You should have received a copy of the GNU General Public License
19 // along with this program; if not, write to the Free Software
20 // Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
23 // (Log is kept at end of this file)
31 #include <Debug/fg_debug.h>
32 #include <Flight/flight.h>
33 #include <Include/fg_constants.h>
34 #include <Math/mat3.h>
35 #include <Math/polar.h>
36 #include <Math/vector.h>
37 #include <Scenery/scenery.h>
38 #include <Time/fg_time.hxx>
43 // This is a record containing current view parameters
44 struct fgVIEW current_view;
47 // Initialize a view structure
48 void fgViewInit(struct fgVIEW *v) {
49 fgPrintf( FG_VIEW, FG_INFO, "Initializing View parameters\n");
52 v->goal_view_offset = 0.0;
56 // Update the view parameters
57 void fgViewUpdate(fgFLIGHT *f, struct fgVIEW *v, fgLIGHT *l) {
58 MAT3vec vec, forward, v0, minus_z;
59 MAT3mat R, TMP, UP, LOCAL, VIEW;
62 scenery.center.x = scenery.next_center.x;
63 scenery.center.y = scenery.next_center.y;
64 scenery.center.z = scenery.next_center.z;
66 // calculate the cartesion coords of the current lat/lon/0 elev
67 v->cur_zero_elev = fgPolarToCart(FG_Longitude, FG_Lat_geocentric,
68 FG_Sea_level_radius * FEET_TO_METER);
69 v->cur_zero_elev.x -= scenery.center.x;
70 v->cur_zero_elev.y -= scenery.center.y;
71 v->cur_zero_elev.z -= scenery.center.z;
73 // calculate view position in current FG view coordinate system
74 v->abs_view_pos = fgPolarToCart(FG_Longitude, FG_Lat_geocentric,
75 FG_Radius_to_vehicle * FEET_TO_METER + 1.0);
76 v->view_pos.x = v->abs_view_pos.x - scenery.center.x;
77 v->view_pos.y = v->abs_view_pos.y - scenery.center.y;
78 v->view_pos.z = v->abs_view_pos.z - scenery.center.z;
80 fgPrintf( FG_VIEW, FG_DEBUG, "Absolute view pos = %.4f, %.4f, %.4f\n",
81 v->abs_view_pos.x, v->abs_view_pos.y, v->abs_view_pos.z);
82 fgPrintf( FG_VIEW, FG_DEBUG, "Relative view pos = %.4f, %.4f, %.4f\n",
83 v->view_pos.x, v->view_pos.y, v->view_pos.z);
85 // Derive the LOCAL aircraft rotation matrix (roll, pitch, yaw)
86 // from FG_T_local_to_body[3][3]
88 // Question: Why is the LaRCsim matrix arranged so differently
89 // than the one we need???
90 LOCAL[0][0] = FG_T_local_to_body_33;
91 LOCAL[0][1] = -FG_T_local_to_body_32;
92 LOCAL[0][2] = -FG_T_local_to_body_31;
94 LOCAL[1][0] = -FG_T_local_to_body_23;
95 LOCAL[1][1] = FG_T_local_to_body_22;
96 LOCAL[1][2] = FG_T_local_to_body_21;
98 LOCAL[2][0] = -FG_T_local_to_body_13;
99 LOCAL[2][1] = FG_T_local_to_body_12;
100 LOCAL[2][2] = FG_T_local_to_body_11;
102 LOCAL[3][0] = LOCAL[3][1] = LOCAL[3][2] = LOCAL[3][3] = 0.0;
104 printf("LaRCsim LOCAL matrix\n");
105 MAT3print(LOCAL, stdout);
107 #ifdef OLD_LOCAL_TO_BODY_CODE
108 // old code to calculate LOCAL matrix calculated from Phi,
109 // Theta, and Psi (roll, pitch, yaw)
111 MAT3_SET_VEC(vec, 0.0, 0.0, 1.0);
112 MAT3rotate(R, vec, FG_Phi);
113 /* printf("Roll matrix\n"); */
114 /* MAT3print(R, stdout); */
116 MAT3_SET_VEC(vec, 0.0, 1.0, 0.0);
117 /* MAT3mult_vec(vec, vec, R); */
118 MAT3rotate(TMP, vec, FG_Theta);
119 /* printf("Pitch matrix\n"); */
120 /* MAT3print(TMP, stdout); */
123 MAT3_SET_VEC(vec, 1.0, 0.0, 0.0);
124 /* MAT3mult_vec(vec, vec, R); */
125 /* MAT3rotate(TMP, vec, FG_Psi - FG_PI_2); */
126 MAT3rotate(TMP, vec, -FG_Psi);
127 /* printf("Yaw matrix\n");
128 MAT3print(TMP, stdout); */
129 MAT3mult(LOCAL, R, TMP);
130 printf("FG derived LOCAL matrix\n");
131 MAT3print(LOCAL, stdout);
132 #endif // OLD_LOCAL_TO_BODY_CODE
134 // Derive the local UP transformation matrix based on *geodetic*
136 MAT3_SET_VEC(vec, 0.0, 0.0, 1.0);
137 MAT3rotate(R, vec, FG_Longitude); // R = rotate about Z axis
138 // printf("Longitude matrix\n");
139 // MAT3print(R, stdout);
141 MAT3_SET_VEC(vec, 0.0, 1.0, 0.0);
142 MAT3mult_vec(vec, vec, R);
143 MAT3rotate(TMP, vec, -FG_Latitude); // TMP = rotate about X axis
144 // printf("Latitude matrix\n");
145 // MAT3print(TMP, stdout);
147 MAT3mult(UP, R, TMP);
148 // printf("Local up matrix\n");
149 // MAT3print(UP, stdout);
151 MAT3_SET_VEC(v->local_up, 1.0, 0.0, 0.0);
152 MAT3mult_vec(v->local_up, v->local_up, UP);
154 // printf( "Local Up = (%.4f, %.4f, %.4f)\n",
155 // v->local_up[0], v->local_up[1], v->local_up[2]);
157 // Alternative method to Derive local up vector based on
158 // *geodetic* coordinates
159 // alt_up = fgPolarToCart(FG_Longitude, FG_Latitude, 1.0);
160 // printf( " Alt Up = (%.4f, %.4f, %.4f)\n",
161 // alt_up.x, alt_up.y, alt_up.z);
163 // Calculate the VIEW matrix
164 MAT3mult(VIEW, LOCAL, UP);
165 // printf("VIEW matrix\n");
166 // MAT3print(VIEW, stdout);
168 // generate the current up, forward, and fwrd-view vectors
169 MAT3_SET_VEC(vec, 1.0, 0.0, 0.0);
170 MAT3mult_vec(v->view_up, vec, VIEW);
172 MAT3_SET_VEC(vec, 0.0, 0.0, 1.0);
173 MAT3mult_vec(forward, vec, VIEW);
174 // printf( "Forward vector is (%.2f,%.2f,%.2f)\n", forward[0], forward[1],
177 MAT3rotate(TMP, v->view_up, v->view_offset);
178 MAT3mult_vec(v->view_forward, forward, TMP);
180 // make a vector to the current view position
181 MAT3_SET_VEC(v0, v->view_pos.x, v->view_pos.y, v->view_pos.z);
183 // Given a vector pointing straight down (-Z), map into onto the
184 // local plane representing "horizontal". This should give us the
185 // local direction for moving "south".
186 MAT3_SET_VEC(minus_z, 0.0, 0.0, -1.0);
187 map_vec_onto_cur_surface_plane(v->local_up, v0, minus_z, v->surface_south);
188 MAT3_NORMALIZE_VEC(v->surface_south, ntmp);
189 // printf( "Surface direction directly south %.2f %.2f %.2f\n",
190 // v->surface_south[0], v->surface_south[1], v->surface_south[2]);
192 // now calculate the surface east vector
193 MAT3rotate(TMP, v->view_up, FG_PI_2);
194 MAT3mult_vec(v->surface_east, v->surface_south, TMP);
195 // printf( "Surface direction directly east %.2f %.2f %.2f\n",
196 // v->surface_east[0], v->surface_east[1], v->surface_east[2]);
197 // printf( "Should be close to zero = %.2f\n",
198 // MAT3_DOT_PRODUCT(v->surface_south, v->surface_east));
203 // Revision 1.4 1998/04/25 22:04:53 curt
204 // Use already calculated LaRCsim values to create the roll/pitch/yaw
205 // transformation matrix (we call it LOCAL)
207 // Revision 1.3 1998/04/25 20:24:02 curt
208 // Cleaned up initialization sequence to eliminate interdependencies
209 // between sun position, lighting, and view position. This creates a
210 // valid single pass initialization path.
212 // Revision 1.2 1998/04/24 00:49:22 curt
213 // Wrapped "#include <config.h>" in "#ifdef HAVE_CONFIG_H"
214 // Trying out some different option parsing code.
215 // Some code reorganization.
217 // Revision 1.1 1998/04/22 13:25:45 curt
218 // C++ - ifing the code.
219 // Starting a bit of reorganization of lighting code.
221 // Revision 1.16 1998/04/18 04:11:29 curt
222 // Moved fg_debug to it's own library, added zlib support.
224 // Revision 1.15 1998/02/20 00:16:24 curt
225 // Thursday's tweaks.
227 // Revision 1.14 1998/02/09 15:07:50 curt
230 // Revision 1.13 1998/02/07 15:29:45 curt
231 // Incorporated HUD changes and struct/typedef changes from Charlie Hotchkiss
232 // <chotchkiss@namg.us.anritsu.com>
234 // Revision 1.12 1998/01/29 00:50:28 curt
235 // Added a view record field for absolute x, y, z position.
237 // Revision 1.11 1998/01/27 00:47:58 curt
238 // Incorporated Paul Bleisch's <pbleisch@acm.org> new debug message
239 // system and commandline/config file processing code.
241 // Revision 1.10 1998/01/19 19:27:09 curt
242 // Merged in make system changes from Bob Kuehne <rpk@sgi.com>
243 // This should simplify things tremendously.
245 // Revision 1.9 1998/01/13 00:23:09 curt
246 // Initial changes to support loading and management of scenery tiles. Note,
247 // there's still a fair amount of work left to be done.
249 // Revision 1.8 1997/12/30 22:22:33 curt
250 // Further integration of event manager.
252 // Revision 1.7 1997/12/30 20:47:45 curt
253 // Integrated new event manager with subsystem initializations.
255 // Revision 1.6 1997/12/22 04:14:32 curt
256 // Aligned sky with sun so dusk/dawn effects can be correct relative to the sun.
258 // Revision 1.5 1997/12/18 04:07:02 curt
259 // Worked on properly translating and positioning the sky dome.
261 // Revision 1.4 1997/12/17 23:13:36 curt
262 // Began working on rendering a sky.
264 // Revision 1.3 1997/12/15 23:54:50 curt
265 // Add xgl wrappers for debugging.
266 // Generate terrain normals on the fly.
268 // Revision 1.2 1997/12/10 22:37:48 curt
269 // Prepended "fg" on the name of all global structures that didn't have it yet.
270 // i.e. "struct WEATHER {}" became "struct fgWEATHER {}"
272 // Revision 1.1 1997/08/27 21:31:17 curt