2 // views.hxx -- 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 # error This library requires C++
35 // #include <Include/fg_types.h>
36 #include <Flight/flight.h>
37 #include <Math/mat3.h>
38 #include <Math/point3d.hxx>
39 #include <Time/fg_time.hxx>
40 #include <Time/light.hxx>
42 #include "options.hxx"
45 // used in views.cxx and tilemgr.cxx
46 #define USE_FAST_FOV_CLIP
49 // Define a structure containing view information
54 // the current offset from forward for viewing
57 // the goal view offset for viewing (used for smooth view changes)
58 double goal_view_offset;
60 // flag forcing update of fov related stuff
63 // fov of view is specified in the y direction, win_ratio is used to
64 // calculate the fov in the X direction = width/height
67 // width & height of window
68 int winWidth, winHeight;
70 // sin and cos of (fov / 2) in Y axis
71 double sin_fov_y, cos_fov_y;
72 double sinlon, coslon;
74 // slope of view frustum edge in eye space Y axis
77 // sin and cos of (fov / 2) in X axis
78 double sin_fov_x, cos_fov_x;
80 // slope of view frustum edge in eye space X axis
83 #if defined( USE_FAST_FOV_CLIP )
84 double fov_x_clip, fov_y_clip;
85 #endif // USE_FAST_FOV_CLIP
87 // View frustum cull ratio (% of tiles culled ... used for
88 // reporting purposes)
91 // Number of triangles rendered;
94 // absolute view position
97 // view position translated to scenery.center
100 // cartesion coordinates of current lon/lat if at sea level
101 // translated to scenery.center*/
102 Point3D cur_zero_elev;
104 // vector in cartesian coordinates from current position to the
105 // postion on the earth's surface the sun is directly over
108 // surface direction to go to head towards sun
109 MAT3vec surface_to_sun;
111 // surface vector heading south
112 MAT3vec surface_south;
114 // surface vector heading east (used to unambiguously align sky
116 MAT3vec surface_east;
118 // local up vector (normal to the plane tangent to the earth's
119 // surface at the spot we are directly above
122 // up vector for the view (usually point straight up through the
123 // top of the aircraft
126 // the vector pointing straight out the nose of the aircraft
127 MAT3vec view_forward;
129 // Transformation matrix for eye coordinates to aircraft coordinates
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];
149 // Initialize a view class
152 void update_globals( fgFLIGHT *f );
154 // Basically, this is a modified version of the Mesa gluLookAt()
155 // function that's been modified slightly so we can capture the
156 // result before sending it off to OpenGL land.
157 void LookAt( GLdouble eyex, GLdouble eyey, GLdouble eyez,
158 GLdouble centerx, GLdouble centery, GLdouble centerz,
159 GLdouble upx, GLdouble upy, GLdouble upz );
161 // Update the view volume, position, and orientation
162 void UpdateViewParams( void );
164 // Update the view parameters
165 void UpdateViewMath( fgFLIGHT *f );
167 // Update the "World to Eye" transformation matrix
168 void UpdateWorldToEye( fgFLIGHT *f );
170 // Update the field of view parameters
171 void UpdateFOV( fgOPTIONS *o );
178 extern fgVIEW current_view;
185 // Revision 1.14 1998/10/16 00:54:04 curt
186 // Converted to Point3D class.
188 // Revision 1.13 1998/09/08 15:04:36 curt
189 // Optimizations by Norman Vine.
191 // Revision 1.12 1998/08/24 20:11:15 curt
192 // Added i/I to toggle full vs. minimal HUD.
193 // Added a --hud-tris vs --hud-culled option.
194 // Moved options accessor funtions to options.hxx.
196 // Revision 1.11 1998/08/20 20:32:35 curt
197 // Reshuffled some of the code in and around views.[ch]xx
199 // Revision 1.10 1998/07/08 14:45:09 curt
200 // polar3d.h renamed to polar3d.hxx
201 // vector.h renamed to vector.hxx
202 // updated audio support so it waits to create audio classes (and tie up
203 // /dev/dsp) until the mpg123 player is finished.
205 // Revision 1.9 1998/07/04 00:52:27 curt
206 // Add my own version of gluLookAt() (which is nearly identical to the
207 // Mesa/glu version.) But, by calculating the Model View matrix our selves
208 // we can save this matrix without having to read it back in from the video
209 // card. This hopefully allows us to save a few cpu cycles when rendering
210 // out the fragments because we can just use glLoadMatrixd() with the
211 // precalculated matrix for each tile rather than doing a push(), translate(),
212 // pop() for every fragment.
214 // Panel status defaults to off for now until it gets a bit more developed.
216 // Extract OpenGL driver info on initialization.
218 // Revision 1.8 1998/05/27 02:24:06 curt
219 // View optimizations by Norman Vine.
221 // Revision 1.7 1998/05/17 16:59:04 curt
222 // First pass at view frustum culling now operational.
224 // Revision 1.6 1998/05/16 13:08:37 curt
225 // C++ - ified views.[ch]xx
226 // Shuffled some additional view parameters into the fgVIEW class.
227 // Changed tile-radius to tile-diameter because it is a much better
229 // Added a WORLD_TO_EYE transformation to views.cxx. This allows us
230 // to transform world space to eye space for view frustum culling.
232 // Revision 1.5 1998/05/02 01:51:02 curt
233 // Updated polartocart conversion routine.
235 // Revision 1.4 1998/04/28 01:20:24 curt
236 // Type-ified fgTIME and fgVIEW.
237 // Added a command line option to disable textures.
239 // Revision 1.3 1998/04/25 22:06:31 curt
240 // Edited cvs log messages in source files ... bad bad bad!
242 // Revision 1.2 1998/04/24 00:49:22 curt
243 // Wrapped "#include <config.h>" in "#ifdef HAVE_CONFIG_H"
244 // Trying out some different option parsing code.
245 // Some code reorganization.
247 // Revision 1.1 1998/04/22 13:25:46 curt
248 // C++ - ifing the code.
249 // Starting a bit of reorganization of lighting code.
251 // Revision 1.11 1998/04/21 17:02:42 curt
252 // Prepairing for C++ integration.
254 // Revision 1.10 1998/02/07 15:29:45 curt
255 // Incorporated HUD changes and struct/typedef changes from Charlie Hotchkiss
256 // <chotchkiss@namg.us.anritsu.com>
258 // Revision 1.9 1998/01/29 00:50:29 curt
259 // Added a view record field for absolute x, y, z position.
261 // Revision 1.8 1998/01/27 00:47:58 curt
262 // Incorporated Paul Bleisch's <pbleisch@acm.org> new debug message
263 // system and commandline/config file processing code.
265 // Revision 1.7 1998/01/22 02:59:38 curt
266 // Changed #ifdef FILE_H to #ifdef _FILE_H
268 // Revision 1.6 1998/01/19 19:27:10 curt
269 // Merged in make system changes from Bob Kuehne <rpk@sgi.com>
270 // This should simplify things tremendously.
272 // Revision 1.5 1997/12/22 04:14:32 curt
273 // Aligned sky with sun so dusk/dawn effects can be correct relative to the sun.
275 // Revision 1.4 1997/12/17 23:13:36 curt
276 // Began working on rendering a sky.
278 // Revision 1.3 1997/12/15 23:54:51 curt
279 // Add xgl wrappers for debugging.
280 // Generate terrain normals on the fly.
282 // Revision 1.2 1997/12/10 22:37:48 curt
283 // Prepended "fg" on the name of all global structures that didn't have it yet.
284 // i.e. "struct WEATHER {}" became "struct fgWEATHER {}"
286 // Revision 1.1 1997/08/27 21:31:18 curt