1 // oursun.hxx -- model earth's sun 2 // 3 // Written by Durk Talsma. Originally started October 1997, for distribution 4 // with the FlightGear project. Version 2 was written in August and 5 // September 1998. This code is based upon algorithms and data kindly 6 // provided by Mr. Paul Schlyter. (pausch@saaf.se). 7 // 8 // Separated out rendering pieces and converted to ssg by Curt Olson, 9 // March 2000 10 // 11 // This library is free software; you can redistribute it and/or 12 // modify it under the terms of the GNU Library General Public 13 // License as published by the Free Software Foundation; either 14 // version 2 of the License, or (at your option) any later version. 15 // 16 // This library is distributed in the hope that it will be useful, 17 // but WITHOUT ANY WARRANTY; without even the implied warranty of 18 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 19 // Library General Public License for more details. 20 // 21 // You should have received a copy of the GNU General Public License 22 // along with this program; if not, write to the Free Software 23 // Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. 24 // 25 // $Id$ 26 27 28 #ifndef _SG_SUN_HXX_ 29 #define _SG_SUN_HXX_ 30 31 #include <osg/Array> 32 #include <osg/Node> 33 #include <osg/MatrixTransform> 34 35 #include <simgear/structure/SGReferenced.hxx> 36 37 #include <simgear/misc/sg_path.hxx> 38 #include <simgear/props/props.hxx> 39 40 class SGSun : public SGReferenced { 41 42 osg::ref_ptr<osg::MatrixTransform> sun_transform; 43 44 osg::ref_ptr<osg::Vec4Array> sun_cl; 45 osg::ref_ptr<osg::Vec4Array> scene_cl; 46 osg::ref_ptr<osg::Vec4Array> ihalo_cl; 47 osg::ref_ptr<osg::Vec4Array> ohalo_cl; 48 osg::ref_ptr<osg::Vec4Array> brilliance_cl; 49 50 double visibility; 51 double prev_sun_angle; 52 // distance of light traveling through the atmosphere 53 double path_distance; 54 double sun_exp2_punch_through; 55 double horizon_angle; 56 57 SGPropertyNode_ptr env_node; 58 59 public: 60 61 // Constructor 62 SGSun( void ); 63 64 // Destructor 65 ~SGSun( void ); 66 67 // return the sun object 68 osg::Node* build( SGPath path, double sun_size, SGPropertyNode *property_tree_Node ); 69 70 // repaint the sun colors based on current value of sun_anglein 71 // degrees relative to verticle 72 // 0 degrees = high noon 73 // 90 degrees = sun rise/set 74 // 180 degrees = darkest midnight 75 bool repaint( double sun_angle, double new_visibility ); 76 77 // reposition the sun at the specified right ascension and 78 // declination, offset by our current position (p) so that it 79 // appears fixed at a great distance from the viewer. Also add in 80 // an optional rotation (i.e. for the current time of day.) 81 bool reposition( double rightAscension, double declination, 82 double sun_dist, double lat, double alt_asl, double sun_angle ); 83 84 // retrun the current color of the sun 85 SGVec4f get_color(); 86 SGVec4f get_scene_color(); 87 }; 88 89 90 #endif // _SG_SUN_HXX_ 91