//
// 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 library is free software; you can redistribute it and/or
+// modify it under the terms of the GNU Library 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
+// This library 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.
+// Library 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.
+// You should have received a copy of the GNU Library General Public
+// License along with this library; if not, write to the
+// Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+// Boston, MA 02111-1307, USA.
//
// $Id$
-#include <plib/ssg.h> // plib include
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+
+#include <plib/sg.h>
+#include <plib/ssg.h>
+
+#include <simgear/math/sg_random.h>
#include "sky.hxx"
// Constructor
SGSky::SGSky( void ) {
+ effective_visibility = visibility = 10000.0;
+
+ // near cloud visibility state variables
+ in_puff = false;
+ puff_length = 0;
+ puff_progression = 0;
+ ramp_up = 0.15;
+ ramp_down = 0.15;
+ // ramp_up = 4.0;
+ // ramp_down = 4.0;
}
// initialize the sky and connect the components to the scene graph at
// the provided branch
-ssgBranch * SGSky::build( double sun_size, double moon_size,
- int nplanets, sgdVec3 *planet_data,
- double planet_dist,
- int nstars, sgdVec3 *star_data, double star_dist )
+void SGSky::build( double sun_size, double moon_size,
+ int nplanets, sgdVec3 *planet_data,
+ double planet_dist,
+ int nstars, sgdVec3 *star_data, double star_dist )
{
- sky_selector = new ssgSelector;
- sky_transform = new ssgTransform;
+ pre_root = new ssgRoot;
+ post_root = new ssgRoot;
+
+ pre_selector = new ssgSelector;
+ post_selector = new ssgSelector;
+
+ pre_transform = new ssgTransform;
+ post_transform = new ssgTransform;
dome = new SGSkyDome;
- sky_transform -> addKid( dome->build() );
+ pre_transform -> addKid( dome->build() );
planets = new SGStars;
- sky_transform -> addKid( planets->build(nplanets, planet_data,
+ pre_transform -> addKid( planets->build(nplanets, planet_data,
planet_dist)
);
stars = new SGStars;
- sky_transform -> addKid( stars->build(nstars, star_data, star_dist) );
+ pre_transform -> addKid( stars->build(nstars, star_data, star_dist) );
moon = new SGMoon;
- sky_transform -> addKid( moon->build(tex_path, moon_size) );
+ pre_transform -> addKid( moon->build(tex_path, moon_size) );
oursun = new SGSun;
- sky_transform -> addKid( oursun->build(tex_path, sun_size) );
+ pre_transform -> addKid( oursun->build(tex_path, sun_size) );
+
+ pre_selector->addKid( pre_transform );
+ pre_selector->clrTraversalMaskBits( SSGTRAV_HOT );
+
+ post_selector->addKid( post_transform );
+ post_selector->clrTraversalMaskBits( SSGTRAV_HOT );
- sky_selector->addKid( sky_transform );
- sky_selector->clrTraversalMaskBits( SSGTRAV_HOT );
+ pre_root->addKid( pre_selector );
+ post_root->addKid( post_selector );
- return sky_selector;
+ // add the cloud ssgStates to the material lib
+ FGPath cloud_path;
+
+ cloud_path.set( tex_path.str() );
+ cloud_path.append( "overcast.rgb" );
+ cloud_mats[SG_CLOUD_OVERCAST] = SGCloudMakeState( cloud_path.str() );
+
+ cloud_path.set( tex_path.str() );
+ cloud_path.append( "mostlycloudy.rgba" );
+ cloud_mats[SG_CLOUD_MOSTLY_CLOUDY] = SGCloudMakeState( cloud_path.str() );
+
+ cloud_path.set( tex_path.str() );
+ cloud_path.append( "mostlysunny.rgba" );
+ cloud_mats[SG_CLOUD_MOSTLY_SUNNY] = SGCloudMakeState( cloud_path.str() );
+
+ cloud_path.set( tex_path.str() );
+ cloud_path.append( "cirrus.rgba" );
+ cloud_mats[SG_CLOUD_CIRRUS] = SGCloudMakeState( cloud_path.str() );
}
int nplanets, sgdVec3 *planet_data,
int nstars, sgdVec3 *star_data )
{
- dome->repaint( sky_color, fog_color, sun_angle );
- oursun->repaint( sun_angle );
- moon->repaint( moon_angle );
- planets->repaint( sun_angle, nplanets, planet_data );
- stars->repaint( sun_angle, nstars, star_data );
+ if ( effective_visibility > 1000.0 ) {
+ enable();
+ dome->repaint( sky_color, fog_color, sun_angle, effective_visibility );
+ oursun->repaint( sun_angle );
+ moon->repaint( moon_angle );
+ planets->repaint( sun_angle, nplanets, planet_data );
+ stars->repaint( sun_angle, nstars, star_data );
+
+ for ( int i = 0; i < (int)cloud_layers.size(); ++i ) {
+ cloud_layers[i]->repaint( fog_color );
+ }
+ } else {
+ // turn off sky
+ disable();
+ }
return true;
}
// spin specifies a rotation about the new Z axis (this allows
// additional orientation for the sunrise/set effects and is used by
// the skydome and perhaps clouds.
-bool SGSky::reposition( sgVec3 view_pos, sgVec3 zero_elev,
- double lon, double lat, double spin,
+bool SGSky::reposition( sgVec3 view_pos, sgVec3 zero_elev, sgVec3 view_up,
+ double lon, double lat, double alt, double spin,
double gst,
double sun_ra, double sun_dec, double sun_dist,
double moon_ra, double moon_dec, double moon_dist )
planets->reposition( view_pos, angle );
stars->reposition( view_pos, angle );
+ for ( int i = 0; i < (int)cloud_layers.size(); ++i ) {
+ cloud_layers[i]->reposition( zero_elev, view_up, lon, lat, alt );
+ }
+
return true;
}
+
+
+// draw background portions of the sky ... do this before you draw the
+// rest of your scene.
+void SGSky::preDraw() {
+ ssgCullAndDraw( pre_root );
+}
+
+
+// draw translucent clouds ... do this after you've drawn all the
+// oapaque elements of your scene.
+void SGSky::postDraw( float alt ) {
+ float slop = 5.0; // if we are closer than this to a cloud layer,
+ // don't draw clouds
+
+ int in_cloud = -1; // cloud we are in
+
+ int i;
+
+ // check where we are relative to the cloud layers
+ for ( i = 0; i < (int)cloud_layers.size(); ++i ) {
+ float asl = cloud_layers[i]->get_asl();
+ float thickness = cloud_layers[i]->get_thickness();
+
+ if ( alt < asl - slop ) {
+ // below cloud layer
+ } else if ( alt < asl + thickness + slop ) {
+ // in cloud layer
+
+ // bail now and don't draw any clouds
+ in_cloud = i;
+ } else {
+ // above cloud layer
+ }
+ }
+
+ // determine rendering order
+ int pos = 0;
+ while ( pos < (int)cloud_layers.size() &&
+ alt > cloud_layers[pos]->get_asl())
+ {
+ ++pos;
+ }
+
+ if ( pos == 0 ) {
+ // we are below all the cloud layers, draw top to bottom
+ for ( i = cloud_layers.size() - 1; i >= 0; --i ) {
+ if ( i != in_cloud ) {
+ cloud_layers[i]->draw();
+ }
+ }
+ } else if ( pos >= (int)cloud_layers.size() ) {
+ // we are above all the cloud layers, draw bottom to top
+ for ( i = 0; i < (int)cloud_layers.size(); ++i ) {
+ if ( i != in_cloud ) {
+ cloud_layers[i]->draw();
+ }
+ }
+ } else {
+ // we are between cloud layers, draw lower layers bottom to
+ // top and upper layers top to bottom
+ for ( i = 0; i < pos; ++i ) {
+ if ( i != in_cloud ) {
+ cloud_layers[i]->draw();
+ }
+ }
+ for ( i = cloud_layers.size() - 1; i >= pos; --i ) {
+ if ( i != in_cloud ) {
+ cloud_layers[i]->draw();
+ }
+ }
+ }
+}
+
+
+void SGSky::add_cloud_layer( double asl, double thickness,
+ double transition, double span,
+ ssgSimpleState *state ) {
+ SGCloudLayer *layer = new SGCloudLayer;
+ layer->build( span, asl, thickness, transition, state );
+
+ layer_list_iterator current = cloud_layers.begin();
+ layer_list_iterator last = cloud_layers.end();
+ while ( current != last && (*current)->get_asl() < asl ) {
+ ++current;
+ }
+
+ if ( current != last ) {
+ cloud_layers.insert( current, layer );
+ } else {
+ cloud_layers.push_back( layer );
+ }
+
+ // for ( int i = 0; i < (int)cloud_layers.size(); ++i ) {
+ // cout << "layer " << i << " = " << cloud_layers[i]->get_asl() << endl;
+ // }
+ // cout << endl;
+}
+
+
+void SGSky::add_cloud_layer( double asl, double thickness,
+ double transition, double span,
+ const string &tex_path ) {
+ ssgSimpleState *state = SGCloudMakeState( tex_path );
+ add_cloud_layer( asl, thickness, transition, span, state );
+}
+
+
+void SGSky::add_cloud_layer( double asl, double thickness,
+ double transition, double span,
+ SGCloudType type ) {
+ if ( type > 0 && type < SG_MAX_CLOUD_TYPES ) {
+ add_cloud_layer( asl, thickness, transition, span, cloud_mats[type] );
+ }
+}
+
+
+// modify the current visibility based on cloud layers, thickness,
+// transition range, and simulated "puffs".
+void SGSky::modify_vis( float alt, float time_factor ) {
+ float effvis = visibility;
+
+ for ( int i = 0; i < (int)cloud_layers.size(); ++i ) {
+ float asl = cloud_layers[i]->get_asl();
+ float thickness = cloud_layers[i]->get_thickness();
+ float transition = cloud_layers[i]->get_transition();
+
+ double ratio = 1.0;
+
+ if ( alt < asl - transition ) {
+ // below cloud layer
+ ratio = 1.0;
+ } else if ( alt < asl ) {
+ // in lower transition
+ ratio = (asl - alt) / transition;
+ } else if ( alt < asl + thickness ) {
+ // in cloud layer
+ ratio = 0.0;
+ } else if ( alt < asl + thickness + transition ) {
+ // in upper transition
+ ratio = (alt - (asl + thickness)) / transition;
+ } else {
+ // above cloud layer
+ ratio = 1.0;
+ }
+
+ // accumulate effects from multiple cloud layers
+ effvis *= ratio;
+
+ if ( ratio < 1.0 ) {
+ if ( ! in_puff ) {
+ // calc chance of entering cloud puff
+ double rnd = sg_random();
+ double chance = rnd * rnd * rnd;
+ if ( chance > 0.95 /* * (diff - 25) / 50.0 */ ) {
+ in_puff = true;
+ puff_length = sg_random() * 2.0; // up to 2 seconds
+ puff_progression = 0.0;
+ }
+ }
+
+ if ( in_puff ) {
+ // modify actual_visibility based on puff envelope
+
+ if ( puff_progression <= ramp_up ) {
+ double x = 0.5 * SGD_PI * puff_progression / ramp_up;
+ double factor = 1.0 - sin( x );
+ // cout << "ramp up = " << puff_progression
+ // << " factor = " << factor << endl;
+ effvis = effvis * factor;
+ } else if ( puff_progression >= ramp_up + puff_length ) {
+ double x = 0.5 * SGD_PI *
+ (puff_progression - (ramp_up + puff_length)) /
+ ramp_down;
+ double factor = sin( x );
+ // cout << "ramp down = "
+ // << puff_progression - (ramp_up + puff_length)
+ // << " factor = " << factor << endl;
+ effvis = effvis * factor;
+ } else {
+ effvis = 0.0;
+ }
+
+ /* cout << "len = " << puff_length
+ << " x = " << x
+ << " factor = " << factor
+ << " actual_visibility = " << actual_visibility
+ << endl; */
+
+ // time_factor = ( global_multi_loop *
+ // current_options.get_speed_up() ) /
+ // (double)current_options.get_model_hz();
+
+ puff_progression += time_factor;
+ // cout << "time factor = " << time_factor << endl;
+
+ /* cout << "gml = " << global_multi_loop
+ << " speed up = " << current_options.get_speed_up()
+ << " hz = " << current_options.get_model_hz() << endl;
+ */
+
+ if ( puff_progression > puff_length + ramp_up + ramp_down) {
+ in_puff = false;
+ }
+ }
+
+ // never let visibility drop below 25 meters
+ if ( effvis <= 25.0 ) {
+ effvis = 25.0;
+ }
+ }
+ } // for
+
+ effective_visibility = effvis;
+}
+