/************************************************************************** * views.c -- data structures and routines for managing and view parameters. * * Written by Curtis Olson, started August 1997. * * Copyright (C) 1997 Curtis L. Olson - curt@infoplane.com * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License as * published by the Free Software Foundation; either version 2 of the * License, or (at your option) any later version. * * This program is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. * * $Id$ * (Log is kept at end of this file) **************************************************************************/ #include "views.h" #include "../Include/constants.h" #include "../Flight/flight.h" #include "../Math/mat3.h" #include "../Math/polar.h" #include "../Math/vector.h" #include "../Scenery/scenery.h" #include "../Time/fg_time.h" /* This is a record containing current view parameters */ struct fgVIEW current_view; /* Initialize a view structure */ void fgViewInit(struct fgVIEW *v) { printf("Initializing View parameters\n"); v->view_offset = 0.0; v->goal_view_offset = 0.0; } /* Update the view parameters */ void fgViewUpdate(struct fgFLIGHT *f, struct fgVIEW *v, struct fgLIGHT *l) { MAT3vec vec, forward, v0, minus_z; MAT3mat R, TMP, UP, LOCAL, VIEW; double ntmp; /* calculate the cartesion coords of the current lat/lon/0 elev */ v->cur_zero_elev = fgPolarToCart(FG_Longitude, FG_Lat_geocentric, FG_Sea_level_radius * FEET_TO_METER); v->cur_zero_elev.x -= scenery.center.x; v->cur_zero_elev.y -= scenery.center.y; v->cur_zero_elev.z -= scenery.center.z; /* calculate view position in current FG view coordinate system */ v->view_pos = fgPolarToCart(FG_Longitude, FG_Lat_geocentric, FG_Radius_to_vehicle * FEET_TO_METER + 1.0); v->view_pos.x -= scenery.center.x; v->view_pos.y -= scenery.center.y; v->view_pos.z -= scenery.center.z; /* printf("View pos = %.4f, %.4f, %.4f\n", v->view_pos.x, v->view_pos.y, v->view_pos.z); */ /* make a vector to the current view position */ MAT3_SET_VEC(v0, v->view_pos.x, v->view_pos.y, v->view_pos.z); /* calculate vector to sun's position on the earth's surface */ v->to_sun[0] = l->fg_sunpos.x - (v->view_pos.x + scenery.center.x); v->to_sun[1] = l->fg_sunpos.y - (v->view_pos.y + scenery.center.y); v->to_sun[2] = l->fg_sunpos.z - (v->view_pos.z + scenery.center.z); /* printf("Vector to sun = %.2f %.2f %.2f\n", v->to_sun[0], v->to_sun[1], v->to_sun[2]); */ /* Derive the LOCAL aircraft rotation matrix (roll, pitch, yaw) */ MAT3_SET_VEC(vec, 0.0, 0.0, 1.0); MAT3rotate(R, vec, FG_Phi); /* printf("Roll matrix\n"); */ /* MAT3print(R, stdout); */ MAT3_SET_VEC(vec, 0.0, 1.0, 0.0); /* MAT3mult_vec(vec, vec, R); */ MAT3rotate(TMP, vec, FG_Theta); /* printf("Pitch matrix\n"); */ /* MAT3print(TMP, stdout); */ MAT3mult(R, R, TMP); MAT3_SET_VEC(vec, 1.0, 0.0, 0.0); /* MAT3mult_vec(vec, vec, R); */ /* MAT3rotate(TMP, vec, FG_Psi - FG_PI_2); */ MAT3rotate(TMP, vec, -FG_Psi); /* printf("Yaw matrix\n"); MAT3print(TMP, stdout); */ MAT3mult(LOCAL, R, TMP); /* printf("LOCAL matrix\n"); */ /* MAT3print(LOCAL, stdout); */ /* Derive the local UP transformation matrix based on *geodetic* * coordinates */ MAT3_SET_VEC(vec, 0.0, 0.0, 1.0); MAT3rotate(R, vec, FG_Longitude); /* R = rotate about Z axis */ /* printf("Longitude matrix\n"); */ /* MAT3print(R, stdout); */ MAT3_SET_VEC(vec, 0.0, 1.0, 0.0); MAT3mult_vec(vec, vec, R); MAT3rotate(TMP, vec, -FG_Latitude); /* TMP = rotate about X axis */ /* printf("Latitude matrix\n"); */ /* MAT3print(TMP, stdout); */ MAT3mult(UP, R, TMP); /* printf("Local up matrix\n"); */ /* MAT3print(UP, stdout); */ MAT3_SET_VEC(v->local_up, 1.0, 0.0, 0.0); MAT3mult_vec(v->local_up, v->local_up, UP); /* printf("Local Up = (%.4f, %.4f, %.4f)\n", v->local_up[0], v->local_up[1], v->local_up[2]); */ /* Alternative method to Derive local up vector based on * *geodetic* coordinates */ /* alt_up = fgPolarToCart(FG_Longitude, FG_Latitude, 1.0); */ /* printf(" Alt Up = (%.4f, %.4f, %.4f)\n", alt_up.x, alt_up.y, alt_up.z); */ /* Derive the VIEW matrix */ MAT3mult(VIEW, LOCAL, UP); /* printf("VIEW matrix\n"); */ /* MAT3print(VIEW, stdout); */ /* generate the current up, forward, and fwrd-view vectors */ MAT3_SET_VEC(vec, 1.0, 0.0, 0.0); MAT3mult_vec(v->view_up, vec, VIEW); MAT3_SET_VEC(vec, 0.0, 0.0, 1.0); MAT3mult_vec(forward, vec, VIEW); /* printf("Forward vector is (%.2f,%.2f,%.2f)\n", forward[0], forward[1], forward[2]); */ MAT3rotate(TMP, v->view_up, v->view_offset); MAT3mult_vec(v->view_forward, forward, TMP); /* Given a vector from the view position to the point on the * earth's surface the sun is directly over, map into onto the * local plane representing "horizontal". */ map_vec_onto_cur_surface_plane(v->local_up, v0, v->to_sun, v->surface_to_sun); MAT3_NORMALIZE_VEC(v->surface_to_sun, ntmp); /* printf("Surface direction to sun is %.2f %.2f %.2f\n", v->surface_to_sun[0], v->surface_to_sun[1], v->surface_to_sun[2]); */ /* printf("Should be close to zero = %.2f\n", MAT3_DOT_PRODUCT(v->local_up, v->surface_to_sun)); */ /* Given a vector pointing straight down (-Z), map into onto the * local plane representing "horizontal". This should give us the * local direction for moving "south". */ MAT3_SET_VEC(minus_z, 0.0, 0.0, -1.0); map_vec_onto_cur_surface_plane(v->local_up, v0, minus_z, v->surface_south); MAT3_NORMALIZE_VEC(v->surface_south, ntmp); /* printf("Surface direction directly south %.2f %.2f %.2f\n", v->surface_south[0], v->surface_south[1], v->surface_south[2]); */ /* now calculate the surface east vector */ MAT3rotate(TMP, v->view_up, FG_PI_2); MAT3mult_vec(v->surface_east, v->surface_south, TMP); /* printf("Surface direction directly east %.2f %.2f %.2f\n", v->surface_east[0], v->surface_east[1], v->surface_east[2]); */ /* printf("Should be close to zero = %.2f\n", MAT3_DOT_PRODUCT(v->surface_south, v->surface_east)); */ } /* $Log$ /* Revision 1.8 1997/12/30 22:22:33 curt /* Further integration of event manager. /* * Revision 1.7 1997/12/30 20:47:45 curt * Integrated new event manager with subsystem initializations. * * Revision 1.6 1997/12/22 04:14:32 curt * Aligned sky with sun so dusk/dawn effects can be correct relative to the sun. * * Revision 1.5 1997/12/18 04:07:02 curt * Worked on properly translating and positioning the sky dome. * * Revision 1.4 1997/12/17 23:13:36 curt * Began working on rendering a sky. * * Revision 1.3 1997/12/15 23:54:50 curt * Add xgl wrappers for debugging. * Generate terrain normals on the fly. * * Revision 1.2 1997/12/10 22:37:48 curt * Prepended "fg" on the name of all global structures that didn't have it yet. * i.e. "struct WEATHER {}" became "struct fgWEATHER {}" * * Revision 1.1 1997/08/27 21:31:17 curt * Initial revision. * */