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
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 // vector in cartesian coordinates from current position to the
110 // postion on the earth's surface the moon is directly over
113 // surface direction to go to head towards moon
114 MAT3vec surface_to_moon;
116 // surface vector heading south
117 MAT3vec surface_south;
119 // surface vector heading east (used to unambiguously align sky
121 MAT3vec surface_east;
123 // local up vector (normal to the plane tangent to the earth's
124 // surface at the spot we are directly above
127 // up vector for the view (usually point straight up through the
128 // top of the aircraft
131 // the vector pointing straight out the nose of the aircraft
132 MAT3vec view_forward;
134 // Transformation matrix for eye coordinates to aircraft coordinates
137 // Transformation matrix for the view direction offset relative to
138 // the AIRCRAFT matrix
141 // Transformation matrix for aircraft coordinates to world
145 // Combined transformation from eye coordinates to world coordinates
146 MAT3mat EYE_TO_WORLD;
148 // Inverse of EYE_TO_WORLD which is a transformation from world
149 // coordinates to eye coordinates
150 MAT3mat WORLD_TO_EYE;
152 // Current model view matrix;
153 GLdouble MODEL_VIEW[16];
163 // Initialize a view class
166 // Basically, this is a modified version of the Mesa gluLookAt()
167 // function that's been modified slightly so we can capture the
168 // result (and use it later) otherwise this all gets calculated in
169 // OpenGL land and we don't have access to the results.
170 void LookAt( GLdouble eyex, GLdouble eyey, GLdouble eyez,
171 GLdouble centerx, GLdouble centery, GLdouble centerz,
172 GLdouble upx, GLdouble upy, GLdouble upz );
174 // Update the view volume, position, and orientation
175 void UpdateViewParams( void );
177 // Flag to request that UpdateFOV() be called next time
178 // UpdateViewMath() is run.
179 inline void force_update_fov_math() { update_fov = true; }
181 // Update the view parameters
182 void UpdateViewMath( FGInterface *f );
184 // Update the "World to Eye" transformation matrix
185 void UpdateWorldToEye( FGInterface *f );
187 // Update the field of view coefficients
188 void UpdateFOV( const fgOPTIONS& o );
190 // accessor functions
191 inline double get_view_offset() const { return view_offset; }
192 inline void set_view_offset( double a ) { view_offset = a; }
193 inline void inc_view_offset( double amt ) { view_offset += amt; }
194 inline double get_goal_view_offset() const { return goal_view_offset; }
195 inline void set_goal_view_offset( double a) { goal_view_offset = a; }
196 inline double get_win_ratio() const { return win_ratio; }
197 inline void set_win_ratio( double r ) { win_ratio = r; }
198 inline int get_winWidth() const { return winWidth; }
199 inline void set_winWidth( int w ) { winWidth = w; }
200 inline int get_winHeight() const { return winHeight; }
201 inline void set_winHeight( int h ) { winHeight = h; }
202 inline double get_slope_y() const { return slope_y; }
203 inline double get_slope_x() const { return slope_x; }
204 #if defined( USE_FAST_FOV_CLIP )
205 inline double get_fov_x_clip() const { return fov_x_clip; }
206 inline double get_fov_y_clip() const { return fov_y_clip; }
207 #endif // USE_FAST_FOV_CLIP
208 inline double get_vfc_ratio() const { return vfc_ratio; }
209 inline void set_vfc_ratio(double r) { vfc_ratio = r; }
210 inline int get_tris_rendered() const { return tris_rendered; }
211 inline void set_tris_rendered( int tris) { tris_rendered = tris; }
212 inline Point3D get_abs_view_pos() const { return abs_view_pos; }
213 inline Point3D get_view_pos() const { return view_pos; }
214 inline Point3D get_cur_zero_elev() const { return cur_zero_elev; }
215 inline double *get_to_sun() { return to_sun; }
216 inline void set_to_sun( double x, double y, double z) {
221 inline double *get_surface_to_sun() { return surface_to_sun; }
222 inline void set_surface_to_sun( double x, double y, double z) {
223 surface_to_sun[0] = x;
224 surface_to_sun[1] = y;
225 surface_to_sun[2] = z;
227 inline double *get_to_moon() { return to_moon; }
228 inline void set_to_moon( double x, double y, double z) {
233 inline double *get_surface_to_moon() { return surface_to_moon; }
234 inline void set_surface_to_moon( double x, double y, double z) {
235 surface_to_moon[0] = x;
236 surface_to_moon[1] = y;
237 surface_to_moon[2] = z;
239 inline double *get_surface_south() { return surface_south; }
240 inline double *get_surface_east() { return surface_east; }
241 inline double *get_local_up() { return local_up; }
242 inline const MAT3mat *get_WORLD_TO_EYE() const { return &WORLD_TO_EYE; }
243 inline GLdouble *get_MODEL_VIEW() { return MODEL_VIEW; }
247 extern FGView current_view;
254 // Revision 1.22 1999/03/22 02:08:15 curt
255 // Changes contributed by Durk Talsma:
257 // Here's a few changes I made to fg-0.58 this weekend. Included are the
258 // following features:
259 // - Sun and moon have a halo
260 // - The moon has a light vector, moon_angle, etc. etc. so that we can have
261 // some moonlight during the night.
262 // - Lot's of small changes tweakes, including some stuff Norman Vine sent
265 // Revision 1.21 1999/02/05 21:29:15 curt
266 // Modifications to incorporate Jon S. Berndts flight model code.
268 // Revision 1.20 1999/02/02 20:13:38 curt
269 // MSVC++ portability changes by Bernie Bright:
271 // Lib/Serial/serial.[ch]xx: Initial Windows support - incomplete.
272 // Simulator/Astro/stars.cxx: typo? included <stdio> instead of <cstdio>
273 // Simulator/Cockpit/hud.cxx: Added Standard headers
274 // Simulator/Cockpit/panel.cxx: Redefinition of default parameter
275 // Simulator/Flight/flight.cxx: Replaced cout with FG_LOG. Deleted <stdio.h>
276 // Simulator/Main/fg_init.cxx:
277 // Simulator/Main/GLUTmain.cxx:
278 // Simulator/Main/options.hxx: Shuffled <fg_serial.hxx> dependency
279 // Simulator/Objects/material.hxx:
280 // Simulator/Time/timestamp.hxx: VC++ friend kludge
281 // Simulator/Scenery/tile.[ch]xx: Fixed using std::X declarations
282 // Simulator/Main/views.hxx: Added a constant
284 // Revision 1.19 1999/02/01 21:33:36 curt
285 // Renamed FlightGear/Simulator/Flight to FlightGear/Simulator/FDM since
286 // Jon accepted my offer to do this and thought it was a good idea.
288 // Revision 1.18 1998/12/11 20:26:30 curt
289 // Fixed view frustum culling accuracy bug so we can look out the sides and
290 // back without tri-stripes dropping out.
292 // Revision 1.17 1998/12/09 18:50:29 curt
293 // Converted "class fgVIEW" to "class FGView" and updated to make data
294 // members private and make required accessor functions.
296 // Revision 1.16 1998/12/05 15:54:25 curt
297 // Renamed class fgFLIGHT to class FGState as per request by JSB.
299 // Revision 1.15 1998/10/16 23:27:56 curt
302 // Revision 1.14 1998/10/16 00:54:04 curt
303 // Converted to Point3D class.
305 // Revision 1.13 1998/09/08 15:04:36 curt
306 // Optimizations by Norman Vine.
308 // Revision 1.12 1998/08/24 20:11:15 curt
309 // Added i/I to toggle full vs. minimal HUD.
310 // Added a --hud-tris vs --hud-culled option.
311 // Moved options accessor funtions to options.hxx.
313 // Revision 1.11 1998/08/20 20:32:35 curt
314 // Reshuffled some of the code in and around views.[ch]xx
316 // Revision 1.10 1998/07/08 14:45:09 curt
317 // polar3d.h renamed to polar3d.hxx
318 // vector.h renamed to vector.hxx
319 // updated audio support so it waits to create audio classes (and tie up
320 // /dev/dsp) until the mpg123 player is finished.
322 // Revision 1.9 1998/07/04 00:52:27 curt
323 // Add my own version of gluLookAt() (which is nearly identical to the
324 // Mesa/glu version.) But, by calculating the Model View matrix our selves
325 // we can save this matrix without having to read it back in from the video
326 // card. This hopefully allows us to save a few cpu cycles when rendering
327 // out the fragments because we can just use glLoadMatrixd() with the
328 // precalculated matrix for each tile rather than doing a push(), translate(),
329 // pop() for every fragment.
331 // Panel status defaults to off for now until it gets a bit more developed.
333 // Extract OpenGL driver info on initialization.
335 // Revision 1.8 1998/05/27 02:24:06 curt
336 // View optimizations by Norman Vine.
338 // Revision 1.7 1998/05/17 16:59:04 curt
339 // First pass at view frustum culling now operational.
341 // Revision 1.6 1998/05/16 13:08:37 curt
342 // C++ - ified views.[ch]xx
343 // Shuffled some additional view parameters into the fgVIEW class.
344 // Changed tile-radius to tile-diameter because it is a much better
346 // Added a WORLD_TO_EYE transformation to views.cxx. This allows us
347 // to transform world space to eye space for view frustum culling.
349 // Revision 1.5 1998/05/02 01:51:02 curt
350 // Updated polartocart conversion routine.
352 // Revision 1.4 1998/04/28 01:20:24 curt
353 // Type-ified fgTIME and fgVIEW.
354 // Added a command line option to disable textures.
356 // Revision 1.3 1998/04/25 22:06:31 curt
357 // Edited cvs log messages in source files ... bad bad bad!
359 // Revision 1.2 1998/04/24 00:49:22 curt
360 // Wrapped "#include <config.h>" in "#ifdef HAVE_CONFIG_H"
361 // Trying out some different option parsing code.
362 // Some code reorganization.
364 // Revision 1.1 1998/04/22 13:25:46 curt
365 // C++ - ifing the code.
366 // Starting a bit of reorganization of lighting code.
368 // Revision 1.11 1998/04/21 17:02:42 curt
369 // Prepairing for C++ integration.
371 // Revision 1.10 1998/02/07 15:29:45 curt
372 // Incorporated HUD changes and struct/typedef changes from Charlie Hotchkiss
373 // <chotchkiss@namg.us.anritsu.com>
375 // Revision 1.9 1998/01/29 00:50:29 curt
376 // Added a view record field for absolute x, y, z position.
378 // Revision 1.8 1998/01/27 00:47:58 curt
379 // Incorporated Paul Bleisch's <pbleisch@acm.org> new debug message
380 // system and commandline/config file processing code.
382 // Revision 1.7 1998/01/22 02:59:38 curt
383 // Changed #ifdef FILE_H to #ifdef _FILE_H
385 // Revision 1.6 1998/01/19 19:27:10 curt
386 // Merged in make system changes from Bob Kuehne <rpk@sgi.com>
387 // This should simplify things tremendously.
389 // Revision 1.5 1997/12/22 04:14:32 curt
390 // Aligned sky with sun so dusk/dawn effects can be correct relative to the sun.
392 // Revision 1.4 1997/12/17 23:13:36 curt
393 // Began working on rendering a sky.
395 // Revision 1.3 1997/12/15 23:54:51 curt
396 // Add xgl wrappers for debugging.
397 // Generate terrain normals on the fly.
399 // Revision 1.2 1997/12/10 22:37:48 curt
400 // Prepended "fg" on the name of all global structures that didn't have it yet.
401 // i.e. "struct WEATHER {}" became "struct fgWEATHER {}"
403 // Revision 1.1 1997/08/27 21:31:18 curt