1 // views.hxx -- data structures and routines for managing and view parameters.
3 // Written by Curtis Olson, started August 1997.
5 // Copyright (C) 1997 Curtis L. Olson - curt@infoplane.com
7 // This program is free software; you can redistribute it and/or
8 // modify it under the terms of the GNU General Public License as
9 // published by the Free Software Foundation; either version 2 of the
10 // License, or (at your option) any later version.
12 // This program is distributed in the hope that it will be useful, but
13 // WITHOUT ANY WARRANTY; without even the implied warranty of
14 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 // General Public License for more details.
17 // You should have received a copy of the GNU General Public License
18 // along with this program; if not, write to the Free Software
19 // Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
22 // (Log is kept at end of this file)
30 # error This library requires C++
34 #include <Flight/flight.hxx>
35 #include <Math/mat3.h>
36 #include <Math/point3d.hxx>
37 #include <Time/fg_time.hxx>
38 #include <Time/light.hxx>
40 #include "options.hxx"
43 // used in views.cxx and tilemgr.cxx
44 #define USE_FAST_FOV_CLIP
47 // Define a structure containing view information
52 // the current offset from forward for viewing
55 // the goal view offset for viewing (used for smooth view changes)
56 double goal_view_offset;
58 // flag forcing update of fov related stuff
61 // fov of view is specified in the y direction, win_ratio is used to
62 // calculate the fov in the X direction = width/height
65 // width & height of window
66 int winWidth, winHeight;
68 // sin and cos of (fov / 2) in Y axis
69 double sin_fov_y, cos_fov_y;
70 double sinlon, coslon;
72 // slope of view frustum edge in eye space Y axis
75 // sin and cos of (fov / 2) in X axis
76 double sin_fov_x, cos_fov_x;
78 // slope of view frustum edge in eye space X axis
81 #if defined( USE_FAST_FOV_CLIP )
82 double fov_x_clip, fov_y_clip;
83 #endif // USE_FAST_FOV_CLIP
85 // View frustum cull ratio (% of tiles culled ... used for
86 // reporting purposes)
89 // Number of triangles rendered;
92 // absolute view position
95 // view position translated to scenery.center
98 // cartesion coordinates of current lon/lat if at sea level
99 // translated to scenery.center*/
100 Point3D cur_zero_elev;
102 // vector in cartesian coordinates from current position to the
103 // postion on the earth's surface the sun is directly over
106 // surface direction to go to head towards sun
107 MAT3vec surface_to_sun;
109 // surface vector heading south
110 MAT3vec surface_south;
112 // surface vector heading east (used to unambiguously align sky
114 MAT3vec surface_east;
116 // local up vector (normal to the plane tangent to the earth's
117 // surface at the spot we are directly above
120 // up vector for the view (usually point straight up through the
121 // top of the aircraft
124 // the vector pointing straight out the nose of the aircraft
125 MAT3vec view_forward;
127 // Transformation matrix for eye coordinates to aircraft coordinates
130 // Transformation matrix for aircraft coordinates to world
134 // Combined transformation from eye coordinates to world coordinates
135 MAT3mat EYE_TO_WORLD;
137 // Inverse of EYE_TO_WORLD which is a transformation from world
138 // coordinates to eye coordinates
139 MAT3mat WORLD_TO_EYE;
141 // Current model view matrix;
142 GLdouble MODEL_VIEW[16];
147 // Initialize a view class
150 void update_globals( FGState *f );
152 // Basically, this is a modified version of the Mesa gluLookAt()
153 // function that's been modified slightly so we can capture the
154 // result (and use it later) otherwise this all gets calculated in
155 // OpenGL land and we don't have access to the results.
156 void LookAt( GLdouble eyex, GLdouble eyey, GLdouble eyez,
157 GLdouble centerx, GLdouble centery, GLdouble centerz,
158 GLdouble upx, GLdouble upy, GLdouble upz );
160 // Update the view volume, position, and orientation
161 void UpdateViewParams( void );
163 // Update the view parameters
164 void UpdateViewMath( FGState *f );
166 // Update the "World to Eye" transformation matrix
167 void UpdateWorldToEye( FGState *f );
169 // Update the field of view parameters
170 void UpdateFOV( fgOPTIONS *o );
177 extern fgVIEW current_view;
184 // Revision 1.16 1998/12/05 15:54:25 curt
185 // Renamed class fgFLIGHT to class FGState as per request by JSB.
187 // Revision 1.15 1998/10/16 23:27:56 curt
190 // Revision 1.14 1998/10/16 00:54:04 curt
191 // Converted to Point3D class.
193 // Revision 1.13 1998/09/08 15:04:36 curt
194 // Optimizations by Norman Vine.
196 // Revision 1.12 1998/08/24 20:11:15 curt
197 // Added i/I to toggle full vs. minimal HUD.
198 // Added a --hud-tris vs --hud-culled option.
199 // Moved options accessor funtions to options.hxx.
201 // Revision 1.11 1998/08/20 20:32:35 curt
202 // Reshuffled some of the code in and around views.[ch]xx
204 // Revision 1.10 1998/07/08 14:45:09 curt
205 // polar3d.h renamed to polar3d.hxx
206 // vector.h renamed to vector.hxx
207 // updated audio support so it waits to create audio classes (and tie up
208 // /dev/dsp) until the mpg123 player is finished.
210 // Revision 1.9 1998/07/04 00:52:27 curt
211 // Add my own version of gluLookAt() (which is nearly identical to the
212 // Mesa/glu version.) But, by calculating the Model View matrix our selves
213 // we can save this matrix without having to read it back in from the video
214 // card. This hopefully allows us to save a few cpu cycles when rendering
215 // out the fragments because we can just use glLoadMatrixd() with the
216 // precalculated matrix for each tile rather than doing a push(), translate(),
217 // pop() for every fragment.
219 // Panel status defaults to off for now until it gets a bit more developed.
221 // Extract OpenGL driver info on initialization.
223 // Revision 1.8 1998/05/27 02:24:06 curt
224 // View optimizations by Norman Vine.
226 // Revision 1.7 1998/05/17 16:59:04 curt
227 // First pass at view frustum culling now operational.
229 // Revision 1.6 1998/05/16 13:08:37 curt
230 // C++ - ified views.[ch]xx
231 // Shuffled some additional view parameters into the fgVIEW class.
232 // Changed tile-radius to tile-diameter because it is a much better
234 // Added a WORLD_TO_EYE transformation to views.cxx. This allows us
235 // to transform world space to eye space for view frustum culling.
237 // Revision 1.5 1998/05/02 01:51:02 curt
238 // Updated polartocart conversion routine.
240 // Revision 1.4 1998/04/28 01:20:24 curt
241 // Type-ified fgTIME and fgVIEW.
242 // Added a command line option to disable textures.
244 // Revision 1.3 1998/04/25 22:06:31 curt
245 // Edited cvs log messages in source files ... bad bad bad!
247 // Revision 1.2 1998/04/24 00:49:22 curt
248 // Wrapped "#include <config.h>" in "#ifdef HAVE_CONFIG_H"
249 // Trying out some different option parsing code.
250 // Some code reorganization.
252 // Revision 1.1 1998/04/22 13:25:46 curt
253 // C++ - ifing the code.
254 // Starting a bit of reorganization of lighting code.
256 // Revision 1.11 1998/04/21 17:02:42 curt
257 // Prepairing for C++ integration.
259 // Revision 1.10 1998/02/07 15:29:45 curt
260 // Incorporated HUD changes and struct/typedef changes from Charlie Hotchkiss
261 // <chotchkiss@namg.us.anritsu.com>
263 // Revision 1.9 1998/01/29 00:50:29 curt
264 // Added a view record field for absolute x, y, z position.
266 // Revision 1.8 1998/01/27 00:47:58 curt
267 // Incorporated Paul Bleisch's <pbleisch@acm.org> new debug message
268 // system and commandline/config file processing code.
270 // Revision 1.7 1998/01/22 02:59:38 curt
271 // Changed #ifdef FILE_H to #ifdef _FILE_H
273 // Revision 1.6 1998/01/19 19:27:10 curt
274 // Merged in make system changes from Bob Kuehne <rpk@sgi.com>
275 // This should simplify things tremendously.
277 // Revision 1.5 1997/12/22 04:14:32 curt
278 // Aligned sky with sun so dusk/dawn effects can be correct relative to the sun.
280 // Revision 1.4 1997/12/17 23:13:36 curt
281 // Began working on rendering a sky.
283 // Revision 1.3 1997/12/15 23:54:51 curt
284 // Add xgl wrappers for debugging.
285 // Generate terrain normals on the fly.
287 // Revision 1.2 1997/12/10 22:37:48 curt
288 // Prepended "fg" on the name of all global structures that didn't have it yet.
289 // i.e. "struct WEATHER {}" became "struct fgWEATHER {}"
291 // Revision 1.1 1997/08/27 21:31:18 curt