/**************************************************************************
* GLmain.c -- top level sim routines
*
* Written by Curtis Olson for OpenGL, started May 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 <math.h>
#include <stdio.h>
#include <stdlib.h>
#include <signal.h> /* for timer routines */
#if defined(__WATCOMC__) || defined(__MSC__)
# include <time.h>
#else
# include <sys/time.h>
#endif
#ifdef GLUT
#include <GL/glut.h>
#include "GLUTkey.h"
#elif MESA_TK
/* assumes -I/usr/include/mesa in compile command */
#include "gltk.h"
#include "GLTKkey.h"
#endif
#include "../aircraft/aircraft.h"
#include "../scenery/scenery.h"
#include "../mat3/mat3.h"
#define DEG_TO_RAD 0.017453292
#define RAD_TO_DEG 57.29577951
/* This is a record containing all the info for the aircraft currently
being operated */
struct aircraft_params current_aircraft;
/* view parameters */
static GLfloat win_ratio = 1.0;
/* sun direction */
static GLfloat sun_vec[4] = {-3.0, 1.0, 2.0, 0.0 };
/* temporary hack */
extern struct mesh *mesh_ptr;
/* Function prototypes */
GLint fgSceneryCompile();
static void fgSceneryDraw();
/* pointer to terrain mesh structure */
static GLint mesh;
/* Another hack */
double fogDensity = 2000.0;
double view_offset = 0.0;
double goal_view_offset = 0.0;
/* Another hack */
#define DEFAULT_MODEL_HZ 20
#define DEFAULT_MULTILOOP 6
double Simtime;
/**************************************************************************
* fgInitVisuals() -- Initialize various GL/view parameters
**************************************************************************/
static void fgInitVisuals() {
/* if the 4th field is 0.0, this specifies a direction ... */
static GLfloat color[4] = { 0.3, 0.7, 0.2, 1.0 };
static GLfloat fogColor[4] = {0.65, 0.65, 0.85, 1.0};
glEnable( GL_DEPTH_TEST );
glFrontFace(GL_CW);
glEnable( GL_CULL_FACE );
/* If enabled, normal vectors specified with glNormal are scaled
to unit length after transformation. See glNormal. */
glEnable( GL_NORMALIZE );
glLightfv( GL_LIGHT0, GL_POSITION, sun_vec );
glEnable( GL_LIGHTING );
glEnable( GL_LIGHT0 );
glMaterialfv( GL_FRONT, GL_AMBIENT_AND_DIFFUSE, color );
glShadeModel( GL_FLAT ); /* glShadeModel( GL_SMOOTH ); */
glEnable( GL_FOG );
glFogi (GL_FOG_MODE, GL_LINEAR);
/* glFogf (GL_FOG_START, 1.0); */
glFogf (GL_FOG_END, fogDensity);
glFogfv (GL_FOG_COLOR, fogColor);
/* glFogf (GL_FOG_DENSITY, fogDensity); */
/* glHint (GL_FOG_HINT, GL_FASTEST); */
glClearColor(0.6, 0.6, 0.9, 1.0);
}
/**************************************************************************
* Update the view volume, position, and orientation
**************************************************************************/
static void fgUpdateViewParams() {
double pos_x, pos_y, pos_z;
struct flight_params *f;
MAT3mat R, TMP;
MAT3vec vec, up, forward, fwrd_view;
f = ¤t_aircraft.flight;
/* Tell GL we are about to modify the projection parameters */
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
gluPerspective(45.0, 1.0/win_ratio, 1.0, 6000.0);
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
/* calculate position in arc seconds */
pos_x = (FG_Longitude * RAD_TO_DEG) * 3600.0;
pos_y = (FG_Latitude * RAD_TO_DEG) * 3600.0;
pos_z = FG_Altitude * 0.01; /* (Convert feet to aproximate arcsecs) */
/* build current rotation matrix */
MAT3_SET_VEC(vec, 1.0, 0.0, 0.0);
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, 0.0, 0.0, -1.0);
/* MAT3mult_vec(vec, vec, R); */
/* MAT3rotate(TMP, vec, M_PI + M_PI_2 + FG_Psi + view_offset); */
MAT3rotate(TMP, vec, FG_Psi - M_PI_2);
/* printf("Yaw matrix\n");
MAT3print(TMP, stdout); */
MAT3mult(R, R, TMP);
/* MAT3print(R, stdout); */
/* generate the current up, forward, and fwrd-view vectors */
MAT3_SET_VEC(vec, 0.0, 0.0, 1.0);
MAT3mult_vec(up, vec, R);
MAT3_SET_VEC(vec, 1.0, 0.0, 0.0);
MAT3mult_vec(forward, vec, R);
printf("Forward vector is (%.2f,%.2f,%.2f)\n", forward[0], forward[1],
forward[2]);
if ( fabs(goal_view_offset - view_offset) < 0.09 ) {
view_offset = goal_view_offset;
} else {
/* move view_offset towards goal_view_offset */
if ( goal_view_offset > view_offset ) {
if ( goal_view_offset - view_offset < M_PI ) {
view_offset += 0.05;
} else {
view_offset -= 0.05;
}
} else {
if ( view_offset - goal_view_offset < M_PI ) {
view_offset -= 0.05;
} else {
view_offset += 0.05;
}
}
if ( view_offset > PI2 ) {
view_offset -= PI2;
} else if ( view_offset < 0 ) {
view_offset += PI2;
}
}
MAT3rotate(TMP, up, view_offset);
MAT3mult_vec(fwrd_view, forward, TMP);
gluLookAt(pos_x, pos_y, pos_z,
pos_x + fwrd_view[0], pos_y + fwrd_view[1], pos_z + fwrd_view[2],
up[0], up[1], up[2]);
glLightfv( GL_LIGHT0, GL_POSITION, sun_vec );
}
/**************************************************************************
* Update all Visuals (redraws anything graphics related)
**************************************************************************/
static void fgUpdateVisuals( void ) {
/* update view volume parameters */
fgUpdateViewParams();
glClear( GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT );
/* Tell GL we are switching to model view parameters */
glMatrixMode(GL_MODELVIEW);
/* glLoadIdentity(); */
/* draw terrain mesh */
fgSceneryDraw();
#ifdef GLUT
glutSwapBuffers();
#elif MESA_TK
tkSwapBuffers();
#endif
}
/**************************************************************************
* Timer management routines
**************************************************************************/
static struct itimerval t, ot;
/* This routine catches the SIGALRM */
void fgTimerCatch() {
struct flight_params *f;
static double lastSimtime = -99.9;
int Overrun;
/* ignore any SIGALRM's until we come back from our EOM iteration */
signal(SIGALRM, SIG_IGN);
f = ¤t_aircraft.flight;
/* printf("In fgTimerCatch()\n"); */
Overrun = (lastSimtime == Simtime);
/* add this back in when you get simtime working */
/* if ( Overrun ) {
printf("OVERRUN!!!\n");
} */
/* update the flight model */
fgFlightModelUpdate(FG_LARCSIM, f, DEFAULT_MULTILOOP);
lastSimtime = Simtime;
signal(SIGALRM, fgTimerCatch);
}
/* this routine initializes the interval timer to generate a SIGALRM after
* the specified interval (dt) */
void fgTimerInit(float dt) {
int terr;
int isec;
float usec;
isec = (int) dt;
usec = 1000000* (dt - (float) isec);
t.it_interval.tv_sec = isec;
t.it_interval.tv_usec = usec;
t.it_value.tv_sec = isec;
t.it_value.tv_usec = usec;
/* printf("fgTimerInit() called\n"); */
fgTimerCatch(); /* set up for SIGALRM signal catch */
terr = setitimer( ITIMER_REAL, &t, &ot );
if (terr) perror("Error returned from setitimer");
}
/**************************************************************************
* Scenery management routines
**************************************************************************/
static void fgSceneryInit() {
/* make terrain mesh */
mesh = fgSceneryCompile();
}
/* create the terrain mesh */
GLint fgSceneryCompile() {
GLint mesh;
mesh = mesh2GL(mesh_ptr);
return(mesh);
}
/* draw the terrain mesh */
static void fgSceneryDraw() {
glCallList(mesh);
}
/* What should we do when we have nothing else to do? How about get
* ready for the next move?*/
static void fgMainLoop( void )
{
fgSlewUpdate();
aircraft_debug(1);
fgUpdateVisuals();
}
/**************************************************************************
* Handle new window size or exposure
**************************************************************************/
static void fgReshape( int width, int height ) {
/* Do this so we can call fgReshape(0,0) ourselves without having to know
* what the values of width & height are. */
if ( (height > 0) && (width > 0) ) {
win_ratio = (GLfloat) height / (GLfloat) width;
}
/* Inform gl of our view window size */
glViewport(0, 0, (GLint)width, (GLint)height);
fgUpdateViewParams();
glClear( GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT );
}
/**************************************************************************
* Main ...
**************************************************************************/
int main( int argc, char *argv[] ) {
struct flight_params *f;
f = ¤t_aircraft.flight;
/* parse the scenery file */
parse_scenery(argv[1]);
#ifdef GLUT
/* initialize GLUT */
glutInit(&argc, argv);
/* Define Display Parameters */
glutInitDisplayMode( GLUT_RGB | GLUT_DEPTH | GLUT_DOUBLE );
/* Define initial window size */
glutInitWindowSize(640, 480);
/* Initialize the main window */
glutCreateWindow("Terrain Demo");
#elif MESA_TK
/* Define initial window size */
tkInitPosition(0, 0, 640, 480);
/* Define Display Parameters */
tkInitDisplayMode( TK_RGB | TK_DEPTH | TK_DOUBLE | TK_DIRECT );
/* Initialize the main window */
if (tkInitWindow("Terrain Demo") == GL_FALSE) {
tkQuit();
}
#endif
/* setup view parameters, only makes GL calls */
fgInitVisuals();
/* Globe Aiport, AZ */
FG_Runway_altitude = 3234.5;
FG_Runway_latitude = 120070.41;
FG_Runway_longitude = -398391.28;
FG_Runway_heading = 102.0 * DEG_TO_RAD;
/* Initial Position */
FG_Latitude = ( 120070.41 / 3600.0 ) * DEG_TO_RAD;
FG_Longitude = ( -398391.28 / 3600.0 ) * DEG_TO_RAD;
FG_Altitude = FG_Runway_altitude + 3.758099;
printf("Initial position is: (%.4f, %.4f, %.2f)\n", FG_Latitude,
FG_Longitude, FG_Altitude);
/* Initial Velocity */
FG_V_north = 0.0 /* 7.287719E+00 */;
FG_V_east = 0.0 /* 1.521770E+03 */;
FG_V_down = 0.0 /* -1.265722E-05 */;
/* Initial Orientation */
FG_Phi = -2.658474E-06;
FG_Theta = 7.401790E-03;
FG_Psi = 282.0 * DEG_TO_RAD;
/* Initial Angular B rates */
FG_P_body = 7.206685E-05;
FG_Q_body = 0.000000E+00;
FG_R_body = 9.492658E-05;
FG_Earth_position_angle = 0.000000E+00;
/* Mass properties and geometry values */
FG_Mass = 8.547270E+01;
FG_I_xx = 1.048000E+03;
FG_I_yy = 3.000000E+03;
FG_I_zz = 3.530000E+03;
FG_I_xz = 0.000000E+00;
/* CG position w.r.t. ref. point */
FG_Dx_cg = 0.000000E+00;
FG_Dy_cg = 0.000000E+00;
FG_Dz_cg = 0.000000E+00;
/* Set initial position and slew parameters */
/* fgSlewInit(-398391.3, 120070.41, 244, 3.1415); */ /* GLOBE Airport */
/* fgSlewInit(-335340,162540, 15, 4.38); */
/* fgSlewInit(-398673.28,120625.64, 53, 4.38); */
fgFlightModelInit(FG_LARCSIM, f, 1.0/(DEFAULT_MODEL_HZ*DEFAULT_MULTILOOP));
/* build all objects */
fgSceneryInit();
/* initialize timer */
fgTimerInit( 1.0 / DEFAULT_MODEL_HZ );
#ifdef GLUT
/* call fgReshape() on window resizes */
glutReshapeFunc( fgReshape );
/* call key() on keyboard event */
glutKeyboardFunc( GLUTkey );
glutSpecialFunc( GLUTspecialkey );
/* call fgMainLoop() whenever there is nothing else to do */
glutIdleFunc( fgMainLoop );
/* draw the scene */
glutDisplayFunc( fgUpdateVisuals );
/* pass control off to the GLUT event handler */
glutMainLoop();
#elif MESA_TK
/* call fgReshape() on expose events */
tkExposeFunc( fgReshape );
/* call fgReshape() on window resizes */
tkReshapeFunc( fgReshape );
/* call key() on keyboard event */
tkKeyDownFunc( GLTKkey );
/* call fgMainLoop() whenever there is nothing else to do */
tkIdleFunc( fgMainLoop );
/* draw the scene */
tkDisplayFunc( fgUpdateVisuals );
/* pass control off to the tk event handler */
tkExec();
#endif
return(0);
}
/* $Log$
/* Revision 1.12 1997/06/02 03:01:38 curt
/* Working on views (side, front, back, transitions, etc.)
/*
* Revision 1.11 1997/05/31 19:16:25 curt
* Elevator trim added.
*
* Revision 1.10 1997/05/31 04:13:52 curt
* WE CAN NOW FLY!!!
*
* Continuing work on the LaRCsim flight model integration.
* Added some MSFS-like keyboard input handling.
*
* Revision 1.9 1997/05/30 19:27:01 curt
* The LaRCsim flight model is starting to look like it is working.
*
* Revision 1.8 1997/05/30 03:54:10 curt
* Made a bit more progress towards integrating the LaRCsim flight model.
*
* Revision 1.7 1997/05/29 22:39:49 curt
* Working on incorporating the LaRCsim flight model.
*
* Revision 1.6 1997/05/29 12:31:39 curt
* Minor tweaks, moving towards general flight model integration.
*
* Revision 1.5 1997/05/29 02:33:23 curt
* Updated to reflect changing interfaces in other "modules."
*
* Revision 1.4 1997/05/27 17:44:31 curt
* Renamed & rearranged variables and routines. Added some initial simple
* timer/alarm routines so the flight model can be updated on a regular
* interval.
*
* Revision 1.3 1997/05/23 15:40:25 curt
* Added GNU copyright headers.
* Fog now works!
*
* Revision 1.2 1997/05/23 00:35:12 curt
* Trying to get fog to work ...
*
* Revision 1.1 1997/05/21 15:57:51 curt
* Renamed due to added GLUT support.
*
* Revision 1.3 1997/05/19 18:22:42 curt
* Parameter tweaking ... starting to stub in fog support.
*
* Revision 1.2 1997/05/17 00:17:34 curt
* Trying to stub in support for standard OpenGL.
*
* Revision 1.1 1997/05/16 16:05:52 curt
* Initial revision.
*
*/