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 <FDM/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
50 // the current offset from forward for viewing
53 // the goal view offset for viewing (used for smooth view changes)
54 double goal_view_offset;
56 // flag forcing update of fov related stuff
59 // fov of view is specified in the y direction, win_ratio is used to
60 // calculate the fov in the X direction = width/height
63 // width & height of window
64 int winWidth, winHeight;
66 // sin and cos of (fov / 2) in Y axis
67 double sin_fov_y, cos_fov_y;
68 double sinlon, coslon;
70 // slope of view frustum edge in eye space Y axis
73 // sin and cos of (fov / 2) in X axis
74 double sin_fov_x, cos_fov_x;
76 // slope of view frustum edge in eye space X axis
79 #if defined( USE_FAST_FOV_CLIP )
80 double fov_x_clip, fov_y_clip;
81 #endif // USE_FAST_FOV_CLIP
83 // View frustum cull ratio (% of tiles culled ... used for
84 // reporting purposes)
87 // Number of triangles rendered;
90 // absolute view position
93 // view position translated to scenery.center
96 // cartesion coordinates of current lon/lat if at sea level
97 // translated to scenery.center*/
98 Point3D cur_zero_elev;
100 // vector in cartesian coordinates from current position to the
101 // postion on the earth's surface the sun is directly over
104 // surface direction to go to head towards sun
105 MAT3vec surface_to_sun;
107 // surface vector heading south
108 MAT3vec surface_south;
110 // surface vector heading east (used to unambiguously align sky
112 MAT3vec surface_east;
114 // local up vector (normal to the plane tangent to the earth's
115 // surface at the spot we are directly above
118 // up vector for the view (usually point straight up through the
119 // top of the aircraft
122 // the vector pointing straight out the nose of the aircraft
123 MAT3vec view_forward;
125 // Transformation matrix for eye coordinates to aircraft coordinates
128 // Transformation matrix for the view direction offset relative to
129 // the AIRCRAFT matrix
132 // Transformation matrix for aircraft coordinates to world
136 // Combined transformation from eye coordinates to world coordinates
137 MAT3mat EYE_TO_WORLD;
139 // Inverse of EYE_TO_WORLD which is a transformation from world
140 // coordinates to eye coordinates
141 MAT3mat WORLD_TO_EYE;
143 // Current model view matrix;
144 GLdouble MODEL_VIEW[16];
154 // Initialize a view class
157 // Basically, this is a modified version of the Mesa gluLookAt()
158 // function that's been modified slightly so we can capture the
159 // result (and use it later) otherwise this all gets calculated in
160 // OpenGL land and we don't have access to the results.
161 void LookAt( GLdouble eyex, GLdouble eyey, GLdouble eyez,
162 GLdouble centerx, GLdouble centery, GLdouble centerz,
163 GLdouble upx, GLdouble upy, GLdouble upz );
165 // Update the view volume, position, and orientation
166 void UpdateViewParams( void );
168 // Flag to request that UpdateFOV() be called next time
169 // UpdateViewMath() is run.
170 inline void force_update_fov_math() { update_fov = true; }
172 // Update the view parameters
173 void UpdateViewMath( FGState *f );
175 // Update the "World to Eye" transformation matrix
176 void UpdateWorldToEye( FGState *f );
178 // Update the field of view coefficients
179 void UpdateFOV( const fgOPTIONS& o );
181 // accessor functions
182 inline double get_view_offset() const { return view_offset; }
183 inline void set_view_offset( double a ) { view_offset = a; }
184 inline void inc_view_offset( double amt ) { view_offset += amt; }
185 inline double get_goal_view_offset() const { return goal_view_offset; }
186 inline void set_goal_view_offset( double a) { goal_view_offset = a; }
187 inline double get_win_ratio() const { return win_ratio; }
188 inline void set_win_ratio( double r ) { win_ratio = r; }
189 inline int get_winWidth() const { return winWidth; }
190 inline void set_winWidth( int w ) { winWidth = w; }
191 inline int get_winHeight() const { return winHeight; }
192 inline void set_winHeight( int h ) { winHeight = h; }
193 inline double get_slope_y() const { return slope_y; }
194 inline double get_slope_x() const { return slope_x; }
195 #if defined( USE_FAST_FOV_CLIP )
196 inline double get_fov_x_clip() const { return fov_x_clip; }
197 inline double get_fov_y_clip() const { return fov_y_clip; }
198 #endif // USE_FAST_FOV_CLIP
199 inline double get_vfc_ratio() const { return vfc_ratio; }
200 inline void set_vfc_ratio(double r) { vfc_ratio = r; }
201 inline int get_tris_rendered() const { return tris_rendered; }
202 inline void set_tris_rendered( int tris) { tris_rendered = tris; }
203 inline Point3D get_abs_view_pos() const { return abs_view_pos; }
204 inline Point3D get_view_pos() const { return view_pos; }
205 inline Point3D get_cur_zero_elev() const { return cur_zero_elev; }
206 inline double *get_to_sun() { return to_sun; }
207 inline void set_to_sun( double x, double y, double z) {
212 inline double *get_surface_to_sun() { return surface_to_sun; }
213 inline void set_surface_to_sun( double x, double y, double z) {
214 surface_to_sun[0] = x;
215 surface_to_sun[1] = y;
216 surface_to_sun[2] = z;
218 inline double *get_surface_south() { return surface_south; }
219 inline double *get_surface_east() { return surface_east; }
220 inline double *get_local_up() { return local_up; }
221 inline MAT3mat *get_WORLD_TO_EYE() const { return &WORLD_TO_EYE; }
222 inline GLdouble *get_MODEL_VIEW() { return MODEL_VIEW; }
226 extern FGView current_view;
233 // Revision 1.19 1999/02/01 21:33:36 curt
234 // Renamed FlightGear/Simulator/Flight to FlightGear/Simulator/FDM since
235 // Jon accepted my offer to do this and thought it was a good idea.
237 // Revision 1.18 1998/12/11 20:26:30 curt
238 // Fixed view frustum culling accuracy bug so we can look out the sides and
239 // back without tri-stripes dropping out.
241 // Revision 1.17 1998/12/09 18:50:29 curt
242 // Converted "class fgVIEW" to "class FGView" and updated to make data
243 // members private and make required accessor functions.
245 // Revision 1.16 1998/12/05 15:54:25 curt
246 // Renamed class fgFLIGHT to class FGState as per request by JSB.
248 // Revision 1.15 1998/10/16 23:27:56 curt
251 // Revision 1.14 1998/10/16 00:54:04 curt
252 // Converted to Point3D class.
254 // Revision 1.13 1998/09/08 15:04:36 curt
255 // Optimizations by Norman Vine.
257 // Revision 1.12 1998/08/24 20:11:15 curt
258 // Added i/I to toggle full vs. minimal HUD.
259 // Added a --hud-tris vs --hud-culled option.
260 // Moved options accessor funtions to options.hxx.
262 // Revision 1.11 1998/08/20 20:32:35 curt
263 // Reshuffled some of the code in and around views.[ch]xx
265 // Revision 1.10 1998/07/08 14:45:09 curt
266 // polar3d.h renamed to polar3d.hxx
267 // vector.h renamed to vector.hxx
268 // updated audio support so it waits to create audio classes (and tie up
269 // /dev/dsp) until the mpg123 player is finished.
271 // Revision 1.9 1998/07/04 00:52:27 curt
272 // Add my own version of gluLookAt() (which is nearly identical to the
273 // Mesa/glu version.) But, by calculating the Model View matrix our selves
274 // we can save this matrix without having to read it back in from the video
275 // card. This hopefully allows us to save a few cpu cycles when rendering
276 // out the fragments because we can just use glLoadMatrixd() with the
277 // precalculated matrix for each tile rather than doing a push(), translate(),
278 // pop() for every fragment.
280 // Panel status defaults to off for now until it gets a bit more developed.
282 // Extract OpenGL driver info on initialization.
284 // Revision 1.8 1998/05/27 02:24:06 curt
285 // View optimizations by Norman Vine.
287 // Revision 1.7 1998/05/17 16:59:04 curt
288 // First pass at view frustum culling now operational.
290 // Revision 1.6 1998/05/16 13:08:37 curt
291 // C++ - ified views.[ch]xx
292 // Shuffled some additional view parameters into the fgVIEW class.
293 // Changed tile-radius to tile-diameter because it is a much better
295 // Added a WORLD_TO_EYE transformation to views.cxx. This allows us
296 // to transform world space to eye space for view frustum culling.
298 // Revision 1.5 1998/05/02 01:51:02 curt
299 // Updated polartocart conversion routine.
301 // Revision 1.4 1998/04/28 01:20:24 curt
302 // Type-ified fgTIME and fgVIEW.
303 // Added a command line option to disable textures.
305 // Revision 1.3 1998/04/25 22:06:31 curt
306 // Edited cvs log messages in source files ... bad bad bad!
308 // Revision 1.2 1998/04/24 00:49:22 curt
309 // Wrapped "#include <config.h>" in "#ifdef HAVE_CONFIG_H"
310 // Trying out some different option parsing code.
311 // Some code reorganization.
313 // Revision 1.1 1998/04/22 13:25:46 curt
314 // C++ - ifing the code.
315 // Starting a bit of reorganization of lighting code.
317 // Revision 1.11 1998/04/21 17:02:42 curt
318 // Prepairing for C++ integration.
320 // Revision 1.10 1998/02/07 15:29:45 curt
321 // Incorporated HUD changes and struct/typedef changes from Charlie Hotchkiss
322 // <chotchkiss@namg.us.anritsu.com>
324 // Revision 1.9 1998/01/29 00:50:29 curt
325 // Added a view record field for absolute x, y, z position.
327 // Revision 1.8 1998/01/27 00:47:58 curt
328 // Incorporated Paul Bleisch's <pbleisch@acm.org> new debug message
329 // system and commandline/config file processing code.
331 // Revision 1.7 1998/01/22 02:59:38 curt
332 // Changed #ifdef FILE_H to #ifdef _FILE_H
334 // Revision 1.6 1998/01/19 19:27:10 curt
335 // Merged in make system changes from Bob Kuehne <rpk@sgi.com>
336 // This should simplify things tremendously.
338 // Revision 1.5 1997/12/22 04:14:32 curt
339 // Aligned sky with sun so dusk/dawn effects can be correct relative to the sun.
341 // Revision 1.4 1997/12/17 23:13:36 curt
342 // Began working on rendering a sky.
344 // Revision 1.3 1997/12/15 23:54:51 curt
345 // Add xgl wrappers for debugging.
346 // Generate terrain normals on the fly.
348 // Revision 1.2 1997/12/10 22:37:48 curt
349 // Prepended "fg" on the name of all global structures that didn't have it yet.
350 // i.e. "struct WEATHER {}" became "struct fgWEATHER {}"
352 // Revision 1.1 1997/08/27 21:31:18 curt