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 // 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 the view direction offset relative to
131 // the AIRCRAFT matrix
134 // Transformation matrix for aircraft coordinates to world
138 // Combined transformation from eye coordinates to world coordinates
139 MAT3mat EYE_TO_WORLD;
141 // Inverse of EYE_TO_WORLD which is a transformation from world
142 // coordinates to eye coordinates
143 MAT3mat WORLD_TO_EYE;
145 // Current model view matrix;
146 GLdouble MODEL_VIEW[16];
156 // Initialize a view class
159 // Basically, this is a modified version of the Mesa gluLookAt()
160 // function that's been modified slightly so we can capture the
161 // result (and use it later) otherwise this all gets calculated in
162 // OpenGL land and we don't have access to the results.
163 void LookAt( GLdouble eyex, GLdouble eyey, GLdouble eyez,
164 GLdouble centerx, GLdouble centery, GLdouble centerz,
165 GLdouble upx, GLdouble upy, GLdouble upz );
167 // Update the view volume, position, and orientation
168 void UpdateViewParams( void );
170 // Flag to request that UpdateFOV() be called next time
171 // UpdateViewMath() is run.
172 inline void force_update_fov_math() { update_fov = true; }
174 // Update the view parameters
175 void UpdateViewMath( FGState *f );
177 // Update the "World to Eye" transformation matrix
178 void UpdateWorldToEye( FGState *f );
180 // Update the field of view coefficients
181 void UpdateFOV( const fgOPTIONS& o );
183 // accessor functions
184 inline double get_view_offset() const { return view_offset; }
185 inline void set_view_offset( double a ) { view_offset = a; }
186 inline void inc_view_offset( double amt ) { view_offset += amt; }
187 inline double get_goal_view_offset() const { return goal_view_offset; }
188 inline void set_goal_view_offset( double a) { goal_view_offset = a; }
189 inline double get_win_ratio() const { return win_ratio; }
190 inline void set_win_ratio( double r ) { win_ratio = r; }
191 inline int get_winWidth() const { return winWidth; }
192 inline void set_winWidth( int w ) { winWidth = w; }
193 inline int get_winHeight() const { return winHeight; }
194 inline void set_winHeight( int h ) { winHeight = h; }
195 inline double get_slope_y() const { return slope_y; }
196 inline double get_slope_x() const { return slope_x; }
197 #if defined( USE_FAST_FOV_CLIP )
198 inline double get_fov_x_clip() const { return fov_x_clip; }
199 inline double get_fov_y_clip() const { return fov_y_clip; }
200 #endif // USE_FAST_FOV_CLIP
201 inline double get_vfc_ratio() const { return vfc_ratio; }
202 inline void set_vfc_ratio(double r) { vfc_ratio = r; }
203 inline int get_tris_rendered() const { return tris_rendered; }
204 inline void set_tris_rendered( int tris) { tris_rendered = tris; }
205 inline Point3D get_abs_view_pos() const { return abs_view_pos; }
206 inline Point3D get_view_pos() const { return view_pos; }
207 inline Point3D get_cur_zero_elev() const { return cur_zero_elev; }
208 inline double *get_to_sun() { return to_sun; }
209 inline void set_to_sun( double x, double y, double z) {
214 inline double *get_surface_to_sun() { return surface_to_sun; }
215 inline void set_surface_to_sun( double x, double y, double z) {
216 surface_to_sun[0] = x;
217 surface_to_sun[1] = y;
218 surface_to_sun[2] = z;
220 inline double *get_surface_south() { return surface_south; }
221 inline double *get_surface_east() { return surface_east; }
222 inline double *get_local_up() { return local_up; }
223 inline const MAT3mat *get_WORLD_TO_EYE() const { return &WORLD_TO_EYE; }
224 inline GLdouble *get_MODEL_VIEW() { return MODEL_VIEW; }
228 extern FGView current_view;
235 // Revision 1.20 1999/02/02 20:13:38 curt
236 // MSVC++ portability changes by Bernie Bright:
238 // Lib/Serial/serial.[ch]xx: Initial Windows support - incomplete.
239 // Simulator/Astro/stars.cxx: typo? included <stdio> instead of <cstdio>
240 // Simulator/Cockpit/hud.cxx: Added Standard headers
241 // Simulator/Cockpit/panel.cxx: Redefinition of default parameter
242 // Simulator/Flight/flight.cxx: Replaced cout with FG_LOG. Deleted <stdio.h>
243 // Simulator/Main/fg_init.cxx:
244 // Simulator/Main/GLUTmain.cxx:
245 // Simulator/Main/options.hxx: Shuffled <fg_serial.hxx> dependency
246 // Simulator/Objects/material.hxx:
247 // Simulator/Time/timestamp.hxx: VC++ friend kludge
248 // Simulator/Scenery/tile.[ch]xx: Fixed using std::X declarations
249 // Simulator/Main/views.hxx: Added a constant
251 // Revision 1.19 1999/02/01 21:33:36 curt
252 // Renamed FlightGear/Simulator/Flight to FlightGear/Simulator/FDM since
253 // Jon accepted my offer to do this and thought it was a good idea.
255 // Revision 1.18 1998/12/11 20:26:30 curt
256 // Fixed view frustum culling accuracy bug so we can look out the sides and
257 // back without tri-stripes dropping out.
259 // Revision 1.17 1998/12/09 18:50:29 curt
260 // Converted "class fgVIEW" to "class FGView" and updated to make data
261 // members private and make required accessor functions.
263 // Revision 1.16 1998/12/05 15:54:25 curt
264 // Renamed class fgFLIGHT to class FGState as per request by JSB.
266 // Revision 1.15 1998/10/16 23:27:56 curt
269 // Revision 1.14 1998/10/16 00:54:04 curt
270 // Converted to Point3D class.
272 // Revision 1.13 1998/09/08 15:04:36 curt
273 // Optimizations by Norman Vine.
275 // Revision 1.12 1998/08/24 20:11:15 curt
276 // Added i/I to toggle full vs. minimal HUD.
277 // Added a --hud-tris vs --hud-culled option.
278 // Moved options accessor funtions to options.hxx.
280 // Revision 1.11 1998/08/20 20:32:35 curt
281 // Reshuffled some of the code in and around views.[ch]xx
283 // Revision 1.10 1998/07/08 14:45:09 curt
284 // polar3d.h renamed to polar3d.hxx
285 // vector.h renamed to vector.hxx
286 // updated audio support so it waits to create audio classes (and tie up
287 // /dev/dsp) until the mpg123 player is finished.
289 // Revision 1.9 1998/07/04 00:52:27 curt
290 // Add my own version of gluLookAt() (which is nearly identical to the
291 // Mesa/glu version.) But, by calculating the Model View matrix our selves
292 // we can save this matrix without having to read it back in from the video
293 // card. This hopefully allows us to save a few cpu cycles when rendering
294 // out the fragments because we can just use glLoadMatrixd() with the
295 // precalculated matrix for each tile rather than doing a push(), translate(),
296 // pop() for every fragment.
298 // Panel status defaults to off for now until it gets a bit more developed.
300 // Extract OpenGL driver info on initialization.
302 // Revision 1.8 1998/05/27 02:24:06 curt
303 // View optimizations by Norman Vine.
305 // Revision 1.7 1998/05/17 16:59:04 curt
306 // First pass at view frustum culling now operational.
308 // Revision 1.6 1998/05/16 13:08:37 curt
309 // C++ - ified views.[ch]xx
310 // Shuffled some additional view parameters into the fgVIEW class.
311 // Changed tile-radius to tile-diameter because it is a much better
313 // Added a WORLD_TO_EYE transformation to views.cxx. This allows us
314 // to transform world space to eye space for view frustum culling.
316 // Revision 1.5 1998/05/02 01:51:02 curt
317 // Updated polartocart conversion routine.
319 // Revision 1.4 1998/04/28 01:20:24 curt
320 // Type-ified fgTIME and fgVIEW.
321 // Added a command line option to disable textures.
323 // Revision 1.3 1998/04/25 22:06:31 curt
324 // Edited cvs log messages in source files ... bad bad bad!
326 // Revision 1.2 1998/04/24 00:49:22 curt
327 // Wrapped "#include <config.h>" in "#ifdef HAVE_CONFIG_H"
328 // Trying out some different option parsing code.
329 // Some code reorganization.
331 // Revision 1.1 1998/04/22 13:25:46 curt
332 // C++ - ifing the code.
333 // Starting a bit of reorganization of lighting code.
335 // Revision 1.11 1998/04/21 17:02:42 curt
336 // Prepairing for C++ integration.
338 // Revision 1.10 1998/02/07 15:29:45 curt
339 // Incorporated HUD changes and struct/typedef changes from Charlie Hotchkiss
340 // <chotchkiss@namg.us.anritsu.com>
342 // Revision 1.9 1998/01/29 00:50:29 curt
343 // Added a view record field for absolute x, y, z position.
345 // Revision 1.8 1998/01/27 00:47:58 curt
346 // Incorporated Paul Bleisch's <pbleisch@acm.org> new debug message
347 // system and commandline/config file processing code.
349 // Revision 1.7 1998/01/22 02:59:38 curt
350 // Changed #ifdef FILE_H to #ifdef _FILE_H
352 // Revision 1.6 1998/01/19 19:27:10 curt
353 // Merged in make system changes from Bob Kuehne <rpk@sgi.com>
354 // This should simplify things tremendously.
356 // Revision 1.5 1997/12/22 04:14:32 curt
357 // Aligned sky with sun so dusk/dawn effects can be correct relative to the sun.
359 // Revision 1.4 1997/12/17 23:13:36 curt
360 // Began working on rendering a sky.
362 // Revision 1.3 1997/12/15 23:54:51 curt
363 // Add xgl wrappers for debugging.
364 // Generate terrain normals on the fly.
366 // Revision 1.2 1997/12/10 22:37:48 curt
367 // Prepended "fg" on the name of all global structures that didn't have it yet.
368 // i.e. "struct WEATHER {}" became "struct fgWEATHER {}"
370 // Revision 1.1 1997/08/27 21:31:18 curt