1 // viewer.cxx -- class for managing a viewer in the flightgear world.
3 // Written by Curtis Olson, started August 1997.
4 // overhaul started October 2000.
5 // partially rewritten by Jim Wilson jim@kelcomaine.com using interface
6 // by David Megginson March 2002
8 // Copyright (C) 1997 - 2000 Curtis L. Olson - http://www.flightgear.org/~curt
10 // This program is free software; you can redistribute it and/or
11 // modify it under the terms of the GNU General Public License as
12 // published by the Free Software Foundation; either version 2 of the
13 // License, or (at your option) any later version.
15 // This program is distributed in the hope that it will be useful, but
16 // WITHOUT ANY WARRANTY; without even the implied warranty of
17 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
18 // General Public License for more details.
20 // You should have received a copy of the GNU General Public License
21 // along with this program; if not, write to the Free Software
22 // Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
32 #include <simgear/compiler.h>
35 #include <simgear/debug/logstream.hxx>
36 #include <simgear/constants.h>
37 #include <simgear/scene/model/placement.hxx>
38 #include <simgear/scene/util/OsgMath.hxx>
40 #include <Main/fg_props.hxx>
41 #include <Main/globals.hxx>
42 #include "CameraGroup.hxx"
44 using namespace flightgear;
46 ////////////////////////////////////////////////////////////////////////
47 // Implementation of FGViewer.
48 ////////////////////////////////////////////////////////////////////////
51 FGViewer::FGViewer( fgViewType Type, bool from_model, int from_model_index,
52 bool at_model, int at_model_index,
53 double damp_roll, double damp_pitch, double damp_heading,
54 double x_offset_m, double y_offset_m, double z_offset_m,
55 double heading_offset_deg, double pitch_offset_deg,
56 double roll_offset_deg,
57 double fov_deg, double aspect_ratio_multiplier,
58 double target_x_offset_m, double target_y_offset_m,
59 double target_z_offset_m, double near_m, bool internal ):
64 _scaling_type(FG_SCALING_MAX),
65 _cameraGroup(CameraGroup::getDefault())
67 _absolute_view_pos = SGVec3d(0, 0, 0);
69 _from_model = from_model;
70 _from_model_index = from_model_index;
72 _at_model_index = at_model_index;
76 _dampFactor = SGVec3d::zeros();
77 _dampOutput = SGVec3d::zeros();
78 _dampTarget = SGVec3d::zeros();
81 _dampFactor[0] = 1.0 / pow(10.0, fabs(damp_roll));
83 _dampFactor[1] = 1.0 / pow(10.0, fabs(damp_pitch));
84 if (damp_heading > 0.0)
85 _dampFactor[2] = 1.0 / pow(10.0, fabs(damp_heading));
87 _offset_m.x() = x_offset_m;
88 _offset_m.y() = y_offset_m;
89 _offset_m.z() = z_offset_m;
90 _heading_offset_deg = heading_offset_deg;
91 _pitch_offset_deg = pitch_offset_deg;
92 _roll_offset_deg = roll_offset_deg;
93 _goal_heading_offset_deg = heading_offset_deg;
94 _goal_pitch_offset_deg = pitch_offset_deg;
95 _goal_roll_offset_deg = roll_offset_deg;
102 _aspect_ratio_multiplier = aspect_ratio_multiplier;
103 _target_offset_m.x() = target_x_offset_m;
104 _target_offset_m.y() = target_y_offset_m;
105 _target_offset_m.z() = target_z_offset_m;
106 _ground_level_nearplane_m = near_m;
107 // a reasonable guess for init, so that the math doesn't blow up
112 FGViewer::~FGViewer( void ) {
131 FGViewer::setType ( int type )
140 FGViewer::setInternal ( bool internal )
142 _internal = internal;
146 FGViewer::setPosition (double lon_deg, double lat_deg, double alt_ft)
149 _position = SGGeod::fromDegFt(lon_deg, lat_deg, alt_ft);
153 FGViewer::setTargetPosition (double lon_deg, double lat_deg, double alt_ft)
156 _target = SGGeod::fromDegFt(lon_deg, lat_deg, alt_ft);
160 FGViewer::setRoll_deg (double roll_deg)
163 _roll_deg = roll_deg;
167 FGViewer::setPitch_deg (double pitch_deg)
170 _pitch_deg = pitch_deg;
174 FGViewer::setHeading_deg (double heading_deg)
177 _heading_deg = heading_deg;
181 FGViewer::setOrientation (double roll_deg, double pitch_deg, double heading_deg)
184 _roll_deg = roll_deg;
185 _pitch_deg = pitch_deg;
186 _heading_deg = heading_deg;
190 FGViewer::setTargetRoll_deg (double target_roll_deg)
193 _target_roll_deg = target_roll_deg;
197 FGViewer::setTargetPitch_deg (double target_pitch_deg)
200 _target_pitch_deg = target_pitch_deg;
204 FGViewer::setTargetHeading_deg (double target_heading_deg)
207 _target_heading_deg = target_heading_deg;
211 FGViewer::setTargetOrientation (double target_roll_deg, double target_pitch_deg, double target_heading_deg)
214 _target_roll_deg = target_roll_deg;
215 _target_pitch_deg = target_pitch_deg;
216 _target_heading_deg = target_heading_deg;
220 FGViewer::setXOffset_m (double x_offset_m)
223 _offset_m.x() = x_offset_m;
227 FGViewer::setYOffset_m (double y_offset_m)
230 _offset_m.y() = y_offset_m;
234 FGViewer::setZOffset_m (double z_offset_m)
237 _offset_m.z() = z_offset_m;
241 FGViewer::setTargetXOffset_m (double target_x_offset_m)
244 _target_offset_m.x() = target_x_offset_m;
248 FGViewer::setTargetYOffset_m (double target_y_offset_m)
251 _target_offset_m.y() = target_y_offset_m;
255 FGViewer::setTargetZOffset_m (double target_z_offset_m)
258 _target_offset_m.z() = target_z_offset_m;
262 FGViewer::setPositionOffsets (double x_offset_m, double y_offset_m, double z_offset_m)
265 _offset_m.x() = x_offset_m;
266 _offset_m.y() = y_offset_m;
267 _offset_m.z() = z_offset_m;
271 FGViewer::setRollOffset_deg (double roll_offset_deg)
274 _roll_offset_deg = roll_offset_deg;
278 FGViewer::setPitchOffset_deg (double pitch_offset_deg)
281 _pitch_offset_deg = pitch_offset_deg;
285 FGViewer::setHeadingOffset_deg (double heading_offset_deg)
288 if (_at_model && (_offset_m.x() == 0.0)&&(_offset_m.z() == 0.0))
290 /* avoid optical effects (e.g. rotating sky) when "looking at" with
291 * heading offsets x==z==0 (view heading cannot change). */
292 _heading_offset_deg = 0.0;
295 _heading_offset_deg = heading_offset_deg;
299 FGViewer::setGoalRollOffset_deg (double goal_roll_offset_deg)
302 _goal_roll_offset_deg = goal_roll_offset_deg;
306 FGViewer::setGoalPitchOffset_deg (double goal_pitch_offset_deg)
309 _goal_pitch_offset_deg = goal_pitch_offset_deg;
310 if ( _goal_pitch_offset_deg < -90 ) {
311 _goal_pitch_offset_deg = -90.0;
313 if ( _goal_pitch_offset_deg > 90.0 ) {
314 _goal_pitch_offset_deg = 90.0;
320 FGViewer::setGoalHeadingOffset_deg (double goal_heading_offset_deg)
323 if (_at_model && (_offset_m.x() == 0.0)&&(_offset_m.z() == 0.0))
325 /* avoid optical effects (e.g. rotating sky) when "looking at" with
326 * heading offsets x==z==0 (view heading cannot change). */
327 _goal_heading_offset_deg = 0.0;
331 _goal_heading_offset_deg = goal_heading_offset_deg;
332 while ( _goal_heading_offset_deg < 0.0 ) {
333 _goal_heading_offset_deg += 360;
335 while ( _goal_heading_offset_deg > 360 ) {
336 _goal_heading_offset_deg -= 360;
341 FGViewer::setOrientationOffsets (double roll_offset_deg, double pitch_offset_deg, double heading_offset_deg)
344 _roll_offset_deg = roll_offset_deg;
345 _pitch_offset_deg = pitch_offset_deg;
346 _heading_offset_deg = heading_offset_deg;
349 // recalc() is done every time one of the setters is called (making the
350 // cached data "dirty") on the next "get". It calculates all the outputs
355 if (_type == FG_LOOKFROM) {
364 // recalculate for LookFrom view type...
366 FGViewer::recalcLookFrom ()
368 // Update location data ...
370 _position = globals->get_aircraft_position();
371 globals->get_aircraft_orientation(_heading_deg, _pitch_deg, _roll_deg);
374 double head = _heading_deg;
375 double pitch = _pitch_deg;
376 double roll = _roll_deg;
377 if ( !_from_model ) {
378 // update from our own data...
379 setDampTarget(roll, pitch, head);
380 getDampOutput(roll, pitch, head);
383 // The rotation rotating from the earth centerd frame to
384 // the horizontal local frame
385 SGQuatd hlOr = SGQuatd::fromLonLat(_position);
387 // The rotation from the horizontal local frame to the basic view orientation
388 SGQuatd hlToBody = SGQuatd::fromYawPitchRollDeg(head, pitch, roll);
390 // The rotation offset, don't know why heading is negative here ...
392 = SGQuatd::fromYawPitchRollDeg(-_heading_offset_deg, _pitch_offset_deg,
395 // Compute the eyepoints orientation and position
396 // wrt the earth centered frame - that is global coorinates
397 SGQuatd ec2body = hlOr*hlToBody;
399 // The cartesian position of the basic view coordinate
400 SGVec3d position = SGVec3d::fromGeod(_position);
402 // This is rotates the x-forward, y-right, z-down coordinate system the where
403 // simulation runs into the OpenGL camera system with x-right, y-up, z-back.
404 SGQuatd q(-0.5, -0.5, 0.5, 0.5);
406 _absolute_view_pos = position + (ec2body*q).backTransform(_offset_m);
407 mViewOrientation = ec2body*mViewOffsetOr*q;
411 FGViewer::recalcLookAt ()
413 // The geodetic position of our target to look at
415 _target = globals->get_aircraft_position();
416 globals->get_aircraft_orientation(_target_heading_deg,
420 // if not model then calculate our own target position...
421 setDampTarget(_target_roll_deg, _target_pitch_deg, _target_heading_deg);
422 getDampOutput(_target_roll_deg, _target_pitch_deg, _target_heading_deg);
425 SGQuatd geodTargetOr = SGQuatd::fromYawPitchRollDeg(_target_heading_deg,
428 SGQuatd geodTargetHlOr = SGQuatd::fromLonLat(_target);
432 _position = globals->get_aircraft_position();
433 globals->get_aircraft_orientation(_heading_deg, _pitch_deg, _roll_deg);
435 // update from our own data, just the rotation here...
436 setDampTarget(_roll_deg, _pitch_deg, _heading_deg);
437 getDampOutput(_roll_deg, _pitch_deg, _heading_deg);
439 SGQuatd geodEyeOr = SGQuatd::fromYawPitchRollDeg(_heading_deg, _pitch_deg, _roll_deg);
440 SGQuatd geodEyeHlOr = SGQuatd::fromLonLat(_position);
442 // the rotation offset, don't know why heading is negative here ...
444 SGQuatd::fromYawPitchRollDeg(-_heading_offset_deg + 180, _pitch_offset_deg,
447 // Offsets to the eye position
448 SGVec3d eyeOff(-_offset_m.z(), _offset_m.x(), -_offset_m.y());
449 SGQuatd ec2eye = geodEyeHlOr*geodEyeOr;
450 SGVec3d eyeCart = SGVec3d::fromGeod(_position);
451 eyeCart += (ec2eye*mViewOffsetOr).backTransform(eyeOff);
453 SGVec3d atCart = SGVec3d::fromGeod(_target);
455 // add target offsets to at_position...
456 SGVec3d target_pos_off(-_target_offset_m.z(), _target_offset_m.x(),
457 -_target_offset_m.y());
458 target_pos_off = (geodTargetHlOr*geodTargetOr).backTransform(target_pos_off);
459 atCart += target_pos_off;
460 eyeCart += target_pos_off;
462 // Compute the eyepoints orientation and position
463 // wrt the earth centered frame - that is global coorinates
464 _absolute_view_pos = eyeCart;
466 // the view direction
467 SGVec3d dir = normalize(atCart - eyeCart);
469 SGVec3d up = ec2eye.backTransform(SGVec3d(0, 0, -1));
470 // rotate -dir to the 2-th unit vector
471 // rotate up to 1-th unit vector
472 // Note that this matches the OpenGL camera coordinate system
473 // with x-right, y-up, z-back.
474 mViewOrientation = SGQuatd::fromRotateTo(-dir, 2, up, 1);
478 FGViewer::setDampTarget(double roll, double pitch, double heading)
480 _dampTarget = SGVec3d(roll, pitch, heading);
484 FGViewer::getDampOutput(double& roll, double& pitch, double& heading)
486 roll = _dampOutput[0];
487 pitch = _dampOutput[1];
488 heading = _dampOutput[2];
493 FGViewer::updateDampOutput(double dt)
495 static FGViewer *last_view = 0;
496 if ((last_view != this) || (dt > 1.0)) {
497 _dampOutput = _dampTarget;
502 const double interval = 0.01;
503 while (dt > interval) {
505 for (unsigned int i=0; i<3; ++i) {
506 if (_dampFactor[i] <= 0.0) {
507 // axis is un-damped, set output to target directly
508 _dampOutput[i] = _dampTarget[i];
512 double d = _dampOutput[i] - _dampTarget[i];
514 _dampOutput[i] -= 360.0;
515 } else if (d < -180.0) {
516 _dampOutput[i] += 360.0;
519 _dampOutput[i] = (_dampTarget[i] * _dampFactor[i]) +
520 (_dampOutput[i] * (1.0 - _dampFactor[i]));
521 } // of axis iteration
524 } // of dt subdivision by interval
528 FGViewer::get_h_fov()
530 double aspectRatio = _cameraGroup->getMasterAspectRatio();
531 switch (_scaling_type) {
532 case FG_SCALING_WIDTH: // h_fov == fov
535 if (aspectRatio < 1.0) {
541 atan(tan(_fov_deg/2 * SG_DEGREES_TO_RADIANS)
542 / (aspectRatio*_aspect_ratio_multiplier))
543 * SG_RADIANS_TO_DEGREES * 2;
554 FGViewer::get_v_fov()
556 double aspectRatio = _cameraGroup->getMasterAspectRatio();
557 switch (_scaling_type) {
558 case FG_SCALING_WIDTH: // h_fov == fov
560 atan(tan(_fov_deg/2 * SG_DEGREES_TO_RADIANS)
561 * (aspectRatio*_aspect_ratio_multiplier))
562 * SG_RADIANS_TO_DEGREES * 2;
564 if (aspectRatio < 1.0) {
567 atan(tan(_fov_deg/2 * SG_DEGREES_TO_RADIANS)
568 * (aspectRatio*_aspect_ratio_multiplier))
569 * SG_RADIANS_TO_DEGREES * 2;
581 FGViewer::update (double dt)
583 updateDampOutput(dt);
586 int dt_ms = int(dt * 1000);
587 for ( i = 0; i < dt_ms; i++ ) {
588 if ( fabs( _goal_heading_offset_deg - _heading_offset_deg) < 1 ) {
589 setHeadingOffset_deg( _goal_heading_offset_deg );
592 // move current_view.headingoffset towards
593 // current_view.goal_view_offset
594 if ( _goal_heading_offset_deg > _heading_offset_deg )
596 if ( _goal_heading_offset_deg - _heading_offset_deg < 180 ){
597 incHeadingOffset_deg( 0.5 );
599 incHeadingOffset_deg( -0.5 );
602 if ( _heading_offset_deg - _goal_heading_offset_deg < 180 ){
603 incHeadingOffset_deg( -0.5 );
605 incHeadingOffset_deg( 0.5 );
608 if ( _heading_offset_deg > 360 ) {
609 incHeadingOffset_deg( -360 );
610 } else if ( _heading_offset_deg < 0 ) {
611 incHeadingOffset_deg( 360 );
616 for ( i = 0; i < dt_ms; i++ ) {
617 if ( fabs( _goal_pitch_offset_deg - _pitch_offset_deg ) < 1 ) {
618 setPitchOffset_deg( _goal_pitch_offset_deg );
621 // move current_view.pitch_offset_deg towards
622 // current_view.goal_pitch_offset
623 if ( _goal_pitch_offset_deg > _pitch_offset_deg )
625 incPitchOffset_deg( 1.0 );
627 incPitchOffset_deg( -1.0 );
629 if ( _pitch_offset_deg > 90 ) {
630 setPitchOffset_deg(90);
631 } else if ( _pitch_offset_deg < -90 ) {
632 setPitchOffset_deg( -90 );
638 for ( i = 0; i < dt_ms; i++ ) {
639 if ( fabs( _goal_roll_offset_deg - _roll_offset_deg ) < 1 ) {
640 setRollOffset_deg( _goal_roll_offset_deg );
643 // move current_view.roll_offset_deg towards
644 // current_view.goal_roll_offset
645 if ( _goal_roll_offset_deg > _roll_offset_deg )
647 incRollOffset_deg( 1.0 );
649 incRollOffset_deg( -1.0 );
651 if ( _roll_offset_deg > 90 ) {
652 setRollOffset_deg(90);
653 } else if ( _roll_offset_deg < -90 ) {
654 setRollOffset_deg( -90 );
659 if( fgGetBool( "/sim/rendering/draw-otw", true ) ) {
660 _cameraGroup->update(toOsg(_absolute_view_pos), toOsg(mViewOrientation));
661 _cameraGroup->setCameraParameters(get_v_fov(), get_aspect_ratio());
665 double FGViewer::get_aspect_ratio() const
667 return _cameraGroup->getMasterAspectRatio();