// viewer.cxx -- class for managing a viewer in the flightgear world. // // Written by Curtis Olson, started August 1997. // overhaul started October 2000. // partially rewritten by Jim Wilson jim@kelcomaine.com using interface // by David Megginson March 2002 // // Copyright (C) 1997 - 2000 Curtis L. Olson - curt@flightgear.org // // 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. // // $Id$ #include #include "fg_props.hxx" #ifdef HAVE_CONFIG_H # include #endif #include #include #include #include #include #include #include #include #include
#include #include #include "viewer.hxx" ////////////////////////////////////////////////////////////////// // Norman's Optimized matrix rotators! // ////////////////////////////////////////////////////////////////// // Since these are pure rotation matrices we can save some bookwork // by considering them to be 3x3 until the very end -- NHV static void MakeVIEW_OFFSET( sgMat4 dst, const float angle1, const sgVec3 axis1, const float angle2, const sgVec3 axis2 ) { // make rotmatrix1 from angle and axis float s = (float) sin ( angle1 ) ; float c = (float) cos ( angle1 ) ; float t = SG_ONE - c ; sgMat3 mat1; float tmp = t * axis1[0]; mat1[0][0] = tmp * axis1[0] + c ; mat1[0][1] = tmp * axis1[1] + s * axis1[2] ; mat1[0][2] = tmp * axis1[2] - s * axis1[1] ; tmp = t * axis1[1]; mat1[1][0] = tmp * axis1[0] - s * axis1[2] ; mat1[1][1] = tmp * axis1[1] + c ; mat1[1][2] = tmp * axis1[2] + s * axis1[0] ; tmp = t * axis1[2]; mat1[2][0] = tmp * axis1[0] + s * axis1[1] ; mat1[2][1] = tmp * axis1[1] - s * axis1[0] ; mat1[2][2] = tmp * axis1[2] + c ; // make rotmatrix2 from angle and axis s = (float) sin ( angle2 ) ; c = (float) cos ( angle2 ) ; t = SG_ONE - c ; sgMat3 mat2; tmp = t * axis2[0]; mat2[0][0] = tmp * axis2[0] + c ; mat2[0][1] = tmp * axis2[1] + s * axis2[2] ; mat2[0][2] = tmp * axis2[2] - s * axis2[1] ; tmp = t * axis2[1]; mat2[1][0] = tmp * axis2[0] - s * axis2[2] ; mat2[1][1] = tmp * axis2[1] + c ; mat2[1][2] = tmp * axis2[2] + s * axis2[0] ; tmp = t * axis2[2]; mat2[2][0] = tmp * axis2[0] + s * axis2[1] ; mat2[2][1] = tmp * axis2[1] - s * axis2[0] ; mat2[2][2] = tmp * axis2[2] + c ; // multiply matrices for ( int j = 0 ; j < 3 ; j++ ) { dst[0][j] = mat2[0][0] * mat1[0][j] + mat2[0][1] * mat1[1][j] + mat2[0][2] * mat1[2][j]; dst[1][j] = mat2[1][0] * mat1[0][j] + mat2[1][1] * mat1[1][j] + mat2[1][2] * mat1[2][j]; dst[2][j] = mat2[2][0] * mat1[0][j] + mat2[2][1] * mat1[1][j] + mat2[2][2] * mat1[2][j]; } // fill in 4x4 matrix elements dst[0][3] = SG_ZERO; dst[1][3] = SG_ZERO; dst[2][3] = SG_ZERO; dst[3][0] = SG_ZERO; dst[3][1] = SG_ZERO; dst[3][2] = SG_ZERO; dst[3][3] = SG_ONE; } //////////////////////////////////////////////////////////////////////// // Implementation of FGViewer. //////////////////////////////////////////////////////////////////////// // Constructor... FGViewer::FGViewer( fgViewType Type, bool from_model, int from_model_index, bool at_model, int at_model_index, double damp_roll, double damp_pitch, double damp_heading, double x_offset_m, double y_offset_m, double z_offset_m, double heading_offset_deg, double pitch_offset_deg, double roll_offset_deg, double fov_deg, double target_x_offset_m, double target_y_offset_m, double target_z_offset_m, double near_m, bool internal ): _dirty(true), _lon_deg(0), _lat_deg(0), _alt_ft(0), _target_lon_deg(0), _target_lat_deg(0), _target_alt_ft(0), _roll_deg(0), _pitch_deg(0), _heading_deg(0), _damp_sync(0), _damp_roll(0), _damp_pitch(0), _damp_heading(0), _scaling_type(FG_SCALING_MAX) { sgdZeroVec3(_absolute_view_pos); _type = Type; _from_model = from_model; _from_model_index = from_model_index; _at_model = at_model; _at_model_index = at_model_index; _internal = internal; if (damp_roll > 0.0) _damp_roll = 1.0 / pow(10, fabs(damp_roll)); if (damp_pitch > 0.0) _damp_pitch = 1.0 / pow(10, fabs(damp_pitch)); if (damp_heading > 0.0) _damp_heading = 1.0 / pow(10, fabs(damp_heading)); _x_offset_m = x_offset_m; _y_offset_m = y_offset_m; _z_offset_m = z_offset_m; _heading_offset_deg = heading_offset_deg; _pitch_offset_deg = pitch_offset_deg; _roll_offset_deg = roll_offset_deg; _goal_heading_offset_deg = heading_offset_deg; _goal_pitch_offset_deg = pitch_offset_deg; _goal_roll_offset_deg = roll_offset_deg; if (fov_deg > 0) { _fov_deg = fov_deg; } else { _fov_deg = 55; } _target_x_offset_m = target_x_offset_m; _target_y_offset_m = target_y_offset_m; _target_z_offset_m = target_z_offset_m; _ground_level_nearplane_m = near_m; // a reasonable guess for init, so that the math doesn't blow up } // Destructor FGViewer::~FGViewer( void ) { } void FGViewer::init () { if ( _from_model ) _location = (SGLocation *) globals->get_aircraft_model()->get3DModel()->getSGLocation(); else _location = (SGLocation *) new SGLocation; if ( _type == FG_LOOKAT ) { if ( _at_model ) _target_location = (SGLocation *) globals->get_aircraft_model()->get3DModel()->getSGLocation(); else _target_location = (SGLocation *) new SGLocation; } } void FGViewer::bind () { } void FGViewer::unbind () { } void FGViewer::setType ( int type ) { if (type == 0) _type = FG_LOOKFROM; if (type == 1) _type = FG_LOOKAT; } void FGViewer::setInternal ( bool internal ) { _internal = internal; } void FGViewer::setLongitude_deg (double lon_deg) { _dirty = true; _lon_deg = lon_deg; } void FGViewer::setLatitude_deg (double lat_deg) { _dirty = true; _lat_deg = lat_deg; } void FGViewer::setAltitude_ft (double alt_ft) { _dirty = true; _alt_ft = alt_ft; } void FGViewer::setPosition (double lon_deg, double lat_deg, double alt_ft) { _dirty = true; _lon_deg = lon_deg; _lat_deg = lat_deg; _alt_ft = alt_ft; } void FGViewer::setTargetLongitude_deg (double lon_deg) { _dirty = true; _target_lon_deg = lon_deg; } void FGViewer::setTargetLatitude_deg (double lat_deg) { _dirty = true; _target_lat_deg = lat_deg; } void FGViewer::setTargetAltitude_ft (double alt_ft) { _dirty = true; _target_alt_ft = alt_ft; } void FGViewer::setTargetPosition (double lon_deg, double lat_deg, double alt_ft) { _dirty = true; _target_lon_deg = lon_deg; _target_lat_deg = lat_deg; _target_alt_ft = alt_ft; } void FGViewer::setRoll_deg (double roll_deg) { _dirty = true; _roll_deg = roll_deg; } void FGViewer::setPitch_deg (double pitch_deg) { _dirty = true; _pitch_deg = pitch_deg; } void FGViewer::setHeading_deg (double heading_deg) { _dirty = true; _heading_deg = heading_deg; } void FGViewer::setOrientation (double roll_deg, double pitch_deg, double heading_deg) { _dirty = true; _roll_deg = roll_deg; _pitch_deg = pitch_deg; _heading_deg = heading_deg; } void FGViewer::setTargetRoll_deg (double target_roll_deg) { _dirty = true; _target_roll_deg = target_roll_deg; } void FGViewer::setTargetPitch_deg (double target_pitch_deg) { _dirty = true; _target_pitch_deg = target_pitch_deg; } void FGViewer::setTargetHeading_deg (double target_heading_deg) { _dirty = true; _target_heading_deg = target_heading_deg; } void FGViewer::setTargetOrientation (double target_roll_deg, double target_pitch_deg, double target_heading_deg) { _dirty = true; _target_roll_deg = target_roll_deg; _target_pitch_deg = target_pitch_deg; _target_heading_deg = target_heading_deg; } void FGViewer::setXOffset_m (double x_offset_m) { _dirty = true; _x_offset_m = x_offset_m; } void FGViewer::setYOffset_m (double y_offset_m) { _dirty = true; _y_offset_m = y_offset_m; } void FGViewer::setZOffset_m (double z_offset_m) { _dirty = true; _z_offset_m = z_offset_m; } void FGViewer::setTargetXOffset_m (double target_x_offset_m) { _dirty = true; _target_x_offset_m = target_x_offset_m; } void FGViewer::setTargetYOffset_m (double target_y_offset_m) { _dirty = true; _target_y_offset_m = target_y_offset_m; } void FGViewer::setTargetZOffset_m (double target_z_offset_m) { _dirty = true; _target_z_offset_m = target_z_offset_m; } void FGViewer::setPositionOffsets (double x_offset_m, double y_offset_m, double z_offset_m) { _dirty = true; _x_offset_m = x_offset_m; _y_offset_m = y_offset_m; _z_offset_m = z_offset_m; } void FGViewer::setRollOffset_deg (double roll_offset_deg) { _dirty = true; _roll_offset_deg = roll_offset_deg; } void FGViewer::setPitchOffset_deg (double pitch_offset_deg) { _dirty = true; _pitch_offset_deg = pitch_offset_deg; } void FGViewer::setHeadingOffset_deg (double heading_offset_deg) { _dirty = true; _heading_offset_deg = heading_offset_deg; } void FGViewer::setGoalRollOffset_deg (double goal_roll_offset_deg) { _dirty = true; _goal_roll_offset_deg = goal_roll_offset_deg; } void FGViewer::setGoalPitchOffset_deg (double goal_pitch_offset_deg) { _dirty = true; _goal_pitch_offset_deg = goal_pitch_offset_deg; if ( _goal_pitch_offset_deg < -90 ) { _goal_pitch_offset_deg = -90.0; } if ( _goal_pitch_offset_deg > 90.0 ) { _goal_pitch_offset_deg = 90.0; } } void FGViewer::setGoalHeadingOffset_deg (double goal_heading_offset_deg) { _dirty = true; _goal_heading_offset_deg = goal_heading_offset_deg; while ( _goal_heading_offset_deg < 0.0 ) { _goal_heading_offset_deg += 360; } while ( _goal_heading_offset_deg > 360 ) { _goal_heading_offset_deg -= 360; } } void FGViewer::setOrientationOffsets (double roll_offset_deg, double pitch_offset_deg, double heading_offset_deg) { _dirty = true; _roll_offset_deg = roll_offset_deg; _pitch_offset_deg = pitch_offset_deg; _heading_offset_deg = heading_offset_deg; } double * FGViewer::get_absolute_view_pos () { if (_dirty) recalc(); return _absolute_view_pos; } float * FGViewer::getRelativeViewPos () { if (_dirty) recalc(); return _relative_view_pos; } float * FGViewer::getZeroElevViewPos () { if (_dirty) recalc(); return _zero_elev_view_pos; } void FGViewer::updateFromModelLocation (SGLocation * location) { sgCopyMat4(LOCAL, location->getCachedTransformMatrix()); } void FGViewer::updateAtModelLocation (SGLocation * location) { sgCopyMat4(ATLOCAL, location->getCachedTransformMatrix()); } void FGViewer::recalcOurOwnLocation (SGLocation * location, double lon_deg, double lat_deg, double alt_ft, double roll_deg, double pitch_deg, double heading_deg) { // update from our own data... dampEyeData(roll_deg, pitch_deg, heading_deg); location->setPosition( lon_deg, lat_deg, alt_ft ); location->setOrientation( roll_deg, pitch_deg, heading_deg ); sgCopyMat4(LOCAL, location->getTransformMatrix(globals->get_scenery()->get_center())); } // recalc() is done every time one of the setters is called (making the // cached data "dirty") on the next "get". It calculates all the outputs // for viewer. void FGViewer::recalc () { if (_type == FG_LOOKFROM) { recalcLookFrom(); } else { recalcLookAt(); } set_clean(); } // recalculate for LookFrom view type... void FGViewer::recalcLookFrom () { sgVec3 right, forward; // sgVec3 eye_pos; sgVec3 position_offset; // eye position offsets (xyz) // LOOKFROM mode... // Update location data... if ( _from_model ) { // update or data from model location updateFromModelLocation(_location); } else { // update from our own data... recalcOurOwnLocation( _location, _lon_deg, _lat_deg, _alt_ft, _roll_deg, _pitch_deg, _heading_deg ); } // copy data from location class to local items... copyLocationData(); // make sg vectors view up, right and forward vectors from LOCAL sgSetVec3( _view_up, LOCAL[2][0], LOCAL[2][1], LOCAL[2][2] ); sgSetVec3( right, LOCAL[1][0], LOCAL[1][1], LOCAL[1][2] ); sgSetVec3( forward, -LOCAL[0][0], -LOCAL[0][1], -LOCAL[0][2] ); // Note that when in "lookfrom" view the "view up" vector is always applied // to the viewer. View up is based on verticle of the aircraft itself. (see // "LOCAL" matrix above) // Orientation Offsets matrix MakeVIEW_OFFSET( VIEW_OFFSET, _heading_offset_deg * SG_DEGREES_TO_RADIANS, _view_up, _pitch_offset_deg * SG_DEGREES_TO_RADIANS, right ); // Make the VIEW matrix. sgSetVec4(VIEW[0], right[0], right[1], right[2],SG_ZERO); sgSetVec4(VIEW[1], forward[0], forward[1], forward[2],SG_ZERO); sgSetVec4(VIEW[2], _view_up[0], _view_up[1], _view_up[2],SG_ZERO); sgSetVec4(VIEW[3], SG_ZERO, SG_ZERO, SG_ZERO,SG_ONE); // rotate model or local matrix to get a matrix to apply Eye Position Offsets sgMat4 VIEW_UP; // L0 forward L1 right L2 up sgCopyVec4(VIEW_UP[0], LOCAL[1]); sgCopyVec4(VIEW_UP[1], LOCAL[2]); sgCopyVec4(VIEW_UP[2], LOCAL[0]); sgZeroVec4(VIEW_UP[3]); // Eye Position Offsets to vector sgSetVec3( position_offset, _x_offset_m, _y_offset_m, _z_offset_m ); sgXformVec3( position_offset, position_offset, VIEW_UP); // add the offsets including rotations to the translation vector sgAddVec3( _view_pos, position_offset ); // multiply the OFFSETS (for heading and pitch) into the VIEW sgPostMultMat4(VIEW, VIEW_OFFSET); // add the position data to the matrix sgSetVec4(VIEW[3], _view_pos[0], _view_pos[1], _view_pos[2],SG_ONE); } void FGViewer::recalcLookAt () { sgVec3 right; sgVec3 eye_pos, at_pos; sgVec3 position_offset; // eye position offsets (xyz) sgVec3 target_position_offset; // target position offsets (xyz) // The position vectors originate from the view point or target location // depending on the type of view. // LOOKAT mode... // Update location data for target... if ( _at_model ) { // update or data from model location updateAtModelLocation(_target_location); } else { // if not model then calculate our own target position... recalcOurOwnLocation( _target_location, _target_lon_deg, _target_lat_deg, _target_alt_ft, _target_roll_deg, _target_pitch_deg, _target_heading_deg ); } // calculate the "at" target object positon relative to eye or view's tile center... sgdVec3 dVec3; sgdSetVec3(dVec3, _location->get_tile_center()[0], _location->get_tile_center()[1], _location->get_tile_center()[2]); sgdSubVec3(dVec3, _target_location->get_absolute_view_pos(globals->get_scenery()->get_center()), dVec3 ); sgSetVec3(at_pos, dVec3[0], dVec3[1], dVec3[2]); // Update location data for eye... if ( _from_model ) { // update or data from model location updateFromModelLocation(_location); } else { // update from our own data, just the rotation here... recalcOurOwnLocation( _location, _lon_deg, _lat_deg, _alt_ft, _roll_deg, _pitch_deg, _heading_deg ); } // save the eye positon... sgCopyVec3(eye_pos, _location->get_view_pos()); // copy data from location class to local items... copyLocationData(); // make sg vectors view up, right and forward vectors from LOCAL sgSetVec3( _view_up, LOCAL[2][0], LOCAL[2][1], LOCAL[2][2] ); sgSetVec3( right, LOCAL[1][0], LOCAL[1][1], LOCAL[1][2] ); // rotate model or local matrix to get a matrix to apply Eye Position Offsets sgMat4 VIEW_UP; // L0 forward L1 right L2 up sgCopyVec4(VIEW_UP[0], LOCAL[1]); sgCopyVec4(VIEW_UP[1], LOCAL[2]); sgCopyVec4(VIEW_UP[2], LOCAL[0]); sgZeroVec4(VIEW_UP[3]); // get Orientation Offsets matrix MakeVIEW_OFFSET( VIEW_OFFSET, (_heading_offset_deg - 180) * SG_DEGREES_TO_RADIANS, _view_up, _pitch_offset_deg * SG_DEGREES_TO_RADIANS, right ); // add in the position offsets sgSetVec3( position_offset, _y_offset_m, _x_offset_m, _z_offset_m ); sgXformVec3( position_offset, position_offset, VIEW_UP); // apply the Orientation offsets sgXformVec3( position_offset, position_offset, VIEW_OFFSET ); // add the Position offsets from object to the eye position sgAddVec3( eye_pos, eye_pos, position_offset ); // add target offsets to at_position... sgSetVec3(target_position_offset, _target_z_offset_m, _target_x_offset_m, _target_y_offset_m ); sgXformVec3(target_position_offset, target_position_offset, ATLOCAL); sgAddVec3( at_pos, at_pos, target_position_offset); sgAddVec3( eye_pos, eye_pos, target_position_offset); // Make the VIEW matrix for a "LOOKAT". sgMakeLookAtMat4( VIEW, eye_pos, at_pos, _view_up ); } // copy results from location class to viewer... // FIXME: some of these should be changed to reference directly to SGLocation... void FGViewer::copyLocationData() { // Get our friendly vectors from the eye location... sgCopyVec3(_zero_elev_view_pos, _location->get_zero_elev()); sgCopyVec3(_relative_view_pos, _location->get_view_pos()); sgdCopyVec3(_absolute_view_pos, _location->get_absolute_view_pos(globals->get_scenery()->get_center())); sgCopyMat4(UP, _location->getCachedUpMatrix()); sgCopyVec3(_world_up, _location->get_world_up()); // these are the vectors that the sun and moon code like to get... sgCopyVec3(_surface_east, _location->get_surface_east()); sgCopyVec3(_surface_south, _location->get_surface_south()); // Update viewer's postion data for the eye location... _lon_deg = _location->getLongitude_deg(); _lat_deg = _location->getLatitude_deg(); _alt_ft = _location->getAltitudeASL_ft(); _roll_deg = _location->getRoll_deg(); _pitch_deg = _location->getPitch_deg(); _heading_deg = _location->getHeading_deg(); // Update viewer's postion data for the target (at object) location if (_type == FG_LOOKAT) { _target_lon_deg = _target_location->getLongitude_deg(); _target_lat_deg = _target_location->getLatitude_deg(); _target_alt_ft = _target_location->getAltitudeASL_ft(); _target_roll_deg = _target_location->getRoll_deg(); _target_pitch_deg = _target_location->getPitch_deg(); _target_heading_deg = _target_location->getHeading_deg(); } // copy coordinates to outputs for viewer... sgCopyVec3(_zero_elev, _zero_elev_view_pos); sgCopyVec3(_view_pos, _relative_view_pos); } void FGViewer::dampEyeData (double &roll_deg, double &pitch_deg, double &heading_deg) { const double interval = 0.01; static FGViewer *last_view = 0; if (last_view != this) { _damp_sync = 0.0; _damped_roll_deg = roll_deg; _damped_pitch_deg = pitch_deg; _damped_heading_deg = heading_deg; last_view = this; return; } if (_damp_sync < interval) { if (_damp_roll > 0.0) roll_deg = _damped_roll_deg; if (_damp_pitch > 0.0) pitch_deg = _damped_pitch_deg; if (_damp_heading > 0.0) heading_deg = _damped_heading_deg; return; } while (_damp_sync >= interval) { _damp_sync -= interval; double d; if (_damp_roll > 0.0) { d = _damped_roll_deg - roll_deg; if (d >= 180.0) _damped_roll_deg -= 360.0; else if (d < -180.0) _damped_roll_deg += 360.0; roll_deg = _damped_roll_deg = roll_deg * _damp_roll + _damped_roll_deg * (1 - _damp_roll); } if (_damp_pitch > 0.0) { d = _damped_pitch_deg - pitch_deg; if (d >= 180.0) _damped_pitch_deg -= 360.0; else if (d < -180.0) _damped_pitch_deg += 360.0; pitch_deg = _damped_pitch_deg = pitch_deg * _damp_pitch + _damped_pitch_deg * (1 - _damp_pitch); } if (_damp_heading > 0.0) { d = _damped_heading_deg - heading_deg; if (d >= 180.0) _damped_heading_deg -= 360.0; else if (d < -180.0) _damped_heading_deg += 360.0; heading_deg = _damped_heading_deg = heading_deg * _damp_heading + _damped_heading_deg * (1 - _damp_heading); } } } double FGViewer::get_h_fov() { switch (_scaling_type) { case FG_SCALING_WIDTH: // h_fov == fov return _fov_deg; case FG_SCALING_MAX: if (_aspect_ratio < 1.0) { // h_fov == fov return _fov_deg; } else { // v_fov == fov return atan(tan(_fov_deg/2 * SG_DEGREES_TO_RADIANS) / _aspect_ratio) * SG_RADIANS_TO_DEGREES * 2; } default: assert(false); } return 0.0; } double FGViewer::get_v_fov() { switch (_scaling_type) { case FG_SCALING_WIDTH: // h_fov == fov return atan(tan(_fov_deg/2 * SG_DEGREES_TO_RADIANS) * _aspect_ratio) * SG_RADIANS_TO_DEGREES * 2; case FG_SCALING_MAX: if (_aspect_ratio < 1.0) { // h_fov == fov return atan(tan(_fov_deg/2 * SG_DEGREES_TO_RADIANS) * _aspect_ratio) * SG_RADIANS_TO_DEGREES * 2; } else { // v_fov == fov return _fov_deg; } default: assert(false); } return 0.0; } void FGViewer::update (double dt) { _damp_sync += dt; int i; int dt_ms = int(dt * 1000); for ( i = 0; i < dt_ms; i++ ) { if ( fabs( _goal_heading_offset_deg - _heading_offset_deg) < 1 ) { setHeadingOffset_deg( _goal_heading_offset_deg ); break; } else { // move current_view.headingoffset towards // current_view.goal_view_offset if ( _goal_heading_offset_deg > _heading_offset_deg ) { if ( _goal_heading_offset_deg - _heading_offset_deg < 180 ){ incHeadingOffset_deg( 0.5 ); } else { incHeadingOffset_deg( -0.5 ); } } else { if ( _heading_offset_deg - _goal_heading_offset_deg < 180 ){ incHeadingOffset_deg( -0.5 ); } else { incHeadingOffset_deg( 0.5 ); } } if ( _heading_offset_deg > 360 ) { incHeadingOffset_deg( -360 ); } else if ( _heading_offset_deg < 0 ) { incHeadingOffset_deg( 360 ); } } } for ( i = 0; i < dt_ms; i++ ) { if ( fabs( _goal_pitch_offset_deg - _pitch_offset_deg ) < 1 ) { setPitchOffset_deg( _goal_pitch_offset_deg ); break; } else { // move current_view.pitch_offset_deg towards // current_view.goal_pitch_offset if ( _goal_pitch_offset_deg > _pitch_offset_deg ) { incPitchOffset_deg( 1.0 ); } else { incPitchOffset_deg( -1.0 ); } if ( _pitch_offset_deg > 90 ) { setPitchOffset_deg(90); } else if ( _pitch_offset_deg < -90 ) { setPitchOffset_deg( -90 ); } } } }