#include "light.hxx"
#include "sunsolver.hxx"
-/**
- * Map i.e. project a vector onto a plane.
- * @param normal (in) normal vector for the plane
- * @param v0 (in) a point on the plane
- * @param vec (in) the vector to map onto the plane
- */
-static SGVec3f map_vec_onto_cur_surface_plane(const SGVec3f& normal,
- const SGVec3f& v0,
- const SGVec3f& vec)
-{
- // calculate a vector "u1" representing the shortest distance from
- // the plane specified by normal and v0 to a point specified by
- // "vec". "u1" represents both the direction and magnitude of
- // this desired distance.
-
- // u1 = ( (normal <dot> vec) / (normal <dot> normal) ) * normal
- SGVec3f u1 = (dot(normal, vec) / dot(normal, normal)) * normal;
-
- // calculate the vector "v" which is the vector "vec" mapped onto
- // the plane specified by "normal" and "v0".
-
- // v = v0 + vec - u1
- SGVec3f v = v0 + vec - u1;
-
- // Calculate the vector "result" which is "v" - "v0" which is a
- // directional vector pointing from v0 towards v
-
- // result = v - v0
- return v - v0;
-}
-
-
// Constructor
FGLight::FGLight ()
: _ambient_tbl( NULL ),
_adj_fog_color(0, 0, 0, 0),
_adj_sky_color(0, 0, 0, 0),
_saturation(1.0),
+ _scattering(0.8),
+ _overcast(0.0),
_dt_total(0)
{
}
void FGLight::bind () {
SGPropertyNode *prop = globals->get_props();
- prop->tie("/sim/time/sun-angle-rad",SGRawValuePointer<double>(&_sun_angle));
+
+ // Write Only
prop->tie("/rendering/scene/saturation",SGRawValuePointer<float>(&_saturation));
+ prop->tie("/rendering/scene/scattering",SGRawValuePointer<float>(&_scattering));
+ prop->tie("/rendering/scene/overcast",SGRawValuePointer<float>(&_overcast));
+
+ _sunAngleRad = prop->getNode("/sim/time/sun-angle-rad", true);
+ _sunAngleRad->setDoubleValue(_sun_angle);
+
+ // Read Only
prop->tie("/rendering/scene/ambient/red",SGRawValuePointer<float>(&_scene_ambient[0]));
prop->tie("/rendering/scene/ambient/green",SGRawValuePointer<float>(&_scene_ambient[1]));
prop->tie("/rendering/scene/ambient/blue",SGRawValuePointer<float>(&_scene_ambient[2]));
void FGLight::unbind () {
SGPropertyNode *prop = globals->get_props();
- prop->untie("/sim/time/sun-angle-rad");
prop->untie("/rendering/scene/saturation");
+ prop->untie("/rendering/scene/scattering");
+ prop->untie("/rendering/scene/overcast");
prop->untie("/rendering/scene/ambient/red");
prop->untie("/rendering/scene/ambient/green");
prop->untie("/rendering/scene/ambient/blue");
if (_saturation < 0.0) _saturation = 0.0;
else if (_saturation > 1.0) _saturation = 1.0;
+ if (_scattering < 0.0) _scattering = 0.0;
+ else if (_scattering > 1.0) _scattering = 1.0;
+ if (_overcast < 0.0) _overcast = 0.0;
+ else if (_overcast > 1.0) _overcast = 1.0;
float ambient = _ambient_tbl->interpolate( deg ) + visibility_inv/10;
float diffuse = _diffuse_tbl->interpolate( deg );
// sky_brightness = 0.15; // used to force a dark sky (when testing)
// set fog and cloud color
- float sqrt_sky_brightness = 1.0 - sqrt(1.0 - sky_brightness);
+ float sqrt_sky_brightness = (1.0 - sqrt(1.0 - sky_brightness))*_scattering;
_fog_color[0] = base_fog_color[0] * sqrt_sky_brightness;
_fog_color[1] = base_fog_color[1] * sqrt_sky_brightness;
_fog_color[2] = base_fog_color[2] * sqrt_sky_brightness;
gamma_correct_rgb( _fog_color.data() );
// set sky color
- _sky_color[0] = base_sky_color[0] * sky_brightness;
- _sky_color[1] = base_sky_color[1] * sky_brightness;
- _sky_color[2] = base_sky_color[2] * sky_brightness;
+ _sky_color[0] = (base_sky_color[0] + (1.0f-base_sky_color[0]) * _overcast) * sky_brightness;
+ _sky_color[1] = (base_sky_color[1] + (1.0f-base_sky_color[1]) * _overcast) * sky_brightness;
+ _sky_color[2] = (base_sky_color[2] + (1.0f-base_sky_color[2]) * _overcast) * sky_brightness;
_sky_color[3] = base_sky_color[3];
gamma_correct_rgb( _sky_color.data() );
_scene_ambient[3] = 1.0;
gamma_correct_rgb( _scene_ambient.data() );
+ SGSky* thesky = globals->get_renderer()->getSky();
+
SGVec4f color = thesky->get_scene_color();
_scene_diffuse[0] = color[0] * diffuse;
_scene_diffuse[1] = color[1] * diffuse;
else
hor_rotation = fmod(hor_rotation, SGD_2PI);
- // revert to unmodified values before usign them.
+ // revert to unmodified values before using them.
//
+ SGSky* thesky = globals->get_renderer()->getSky();
SGVec4f color = thesky->get_scene_color();
gamma_restore_rgb( _fog_color.data(), gamma );
float s_green = color[1]*color[1]*color[1];
float s_blue = color[2]*color[2];
- // interpolate beween the sunrise/sunset color and the color
+ // interpolate between the sunrise/sunset color and the color
// at the opposite direction of this effect. Take in account
// the current visibility.
//
sif = 1e-4;
float rf1 = fabs((hor_rotation - SGD_PI) / SGD_PI); // 0.0 .. 1.0
- float rf2 = avf * pow(rf1*rf1, 1/sif) * 1.0639 * _saturation;
+ float rf2 = avf * pow(rf1*rf1, 1/sif) * 1.0639 * _saturation * _scattering;
float rf3 = 1.0 - rf2;
gamma = system_gamma * (0.9 - sif*avf);
-
_adj_fog_color[0] = rf3 * _fog_color[0] + rf2 * s_red;
_adj_fog_color[1] = rf3 * _fog_color[1] + rf2 * s_green;
_adj_fog_color[2] = rf3 * _fog_color[2] + rf2 * s_blue;
SG_LOG( SG_EVENT, SG_DEBUG, " Updating Sun position" );
SG_LOG( SG_EVENT, SG_DEBUG, " Gst = " << t->getGst() );
- double sun_l;
- double sun_gd_lat;
- fgSunPositionGST(t->getGst(), &sun_l, &sun_gd_lat);
- set_sun_lon(sun_l);
- set_sun_lat(sun_gd_lat);
- SGVec3d sunpos(SGVec3d::fromGeod(SGGeod::fromRad(sun_l, sun_gd_lat)));
+ fgSunPositionGST(t->getGst(), &_sun_lon, &_sun_lat);
+ // It might seem that sun_gc_lat needs to be converted to geodetic
+ // latitude here, but it doesn't. The sun latitude is the latitude
+ // of the point on the earth where the up vector has the same
+ // angle from geocentric Z as the sun direction. But geodetic
+ // latitude is defined as 90 - angle of up vector from Z!
+ SGVec3d sunpos(SGVec3d::fromGeoc(SGGeoc::fromRadM(_sun_lon, _sun_lat,
+ SGGeodesy::EQURAD)));
SG_LOG( SG_EVENT, SG_DEBUG, " t->cur_time = " << t->get_cur_time() );
SG_LOG( SG_EVENT, SG_DEBUG,
- " Sun Geodetic lat = " << sun_gd_lat
- << " Geodetic lat = " << sun_gd_lat );
+ " Sun Geocentric lat = " << _sun_lat
+ << " Geodcentric lat = " << _sun_lat );
// update the sun light vector
sun_vec() = SGVec4f(toVec3f(normalize(sunpos)), 0);
// calculate the sun's relative angle to local up
SGVec3d viewPos = v->get_view_pos();
SGQuatd hlOr = SGQuatd::fromLonLat(SGGeod::fromCart(viewPos));
- SGVec3f world_up = toVec3f(hlOr.backTransform(-SGVec3d::e3()));
- SGVec3f nsun = toVec3f(normalize(sunpos));
+ SGVec3d world_up = hlOr.backTransform(-SGVec3d::e3());
+ SGVec3d nsun = normalize(sunpos);
// cout << "nup = " << nup[0] << "," << nup[1] << ","
// << nup[2] << endl;
// cout << "nsun = " << nsun[0] << "," << nsun[1] << ","
// << nsun[2] << endl;
- set_sun_angle( acos( dot ( world_up, nsun ) ) );
+ _sun_angle = acos( dot ( world_up, nsun ) );
SG_LOG( SG_EVENT, SG_DEBUG, "sun angle relative to current location = "
<< get_sun_angle() );
- // calculate vector to sun's position on the earth's surface
- SGVec3d rel_sunpos = sunpos - v->get_view_pos();
- // vector in cartesian coordinates from current position to the
- // postion on the earth's surface the sun is directly over
- SGVec3f to_sun = toVec3f(rel_sunpos);
- // printf( "Vector to sun = %.2f %.2f %.2f\n",
- // v->to_sun[0], v->to_sun[1], v->to_sun[2]);
-
- // Given a vector from the view position to the point on the
- // earth's surface the sun is directly over, map into onto the
- // local plane representing "horizontal".
-
- // surface direction to go to head towards sun
- SGVec3f surface_to_sun;
- SGVec3f view_pos = toVec3f(v->get_view_pos());
- surface_to_sun = map_vec_onto_cur_surface_plane(world_up, view_pos, to_sun);
- surface_to_sun = normalize(surface_to_sun);
- // cout << "(sg) Surface direction to sun is "
- // << surface_to_sun[0] << ","
- // << surface_to_sun[1] << ","
- // << surface_to_sun[2] << endl;
- // cout << "Should be close to zero = "
- // << sgScalarProductVec3(nup, surface_to_sun) << endl;
-
- // calculate the angle between surface_to_sun and
- // v->get_surface_east(). We do this so we can sort out the
- // acos() ambiguity. I wish I could think of a more efficient
- // way. :-(
- SGVec3f surface_east(toVec3f(hlOr.backTransform(SGVec3d::e2())));
- float east_dot = dot( surface_to_sun, surface_east );
- // cout << " East dot product = " << east_dot << endl;
-
- // calculate the angle between v->surface_to_sun and
- // v->surface_south. this is how much we have to rotate the sky
- // for it to align with the sun
- SGVec3f surface_south(toVec3f(hlOr.backTransform(-SGVec3d::e1())));
- float dot_ = dot( surface_to_sun, surface_south );
- // cout << " Dot product = " << dot << endl;
-
- if (dot_ > 1.0) {
- SG_LOG( SG_ASTRO, SG_INFO,
- "Dot product = " << dot_ << " is greater than 1.0" );
- dot_ = 1.0;
- }
- else if (dot_ < -1.0) {
- SG_LOG( SG_ASTRO, SG_INFO,
- "Dot product = " << dot_ << " is less than -1.0" );
- dot_ = -1.0;
- }
-
- if ( east_dot >= 0 ) {
- set_sun_rotation( acos(dot_) );
- } else {
- set_sun_rotation( -acos(dot_) );
- }
- // cout << " Sky needs to rotate = " << angle << " rads = "
- // << angle * SGD_RADIANS_TO_DEGREES << " degrees." << endl;
+ // Get direction to the sun in the local frame.
+ SGVec3d local_sun_vec = hlOr.transform(nsun);
+
+ // Angle from south. XXX Is this correct in the southern hemisphere?
+ _sun_rotation = atan2(local_sun_vec.x(), -local_sun_vec.y());
+ // cout << " Sky needs to rotate = " << _sun_rotation << " rads = "
+ // << _sun_rotation * SGD_RADIANS_TO_DEGREES << " degrees." << endl;
+
+ _sunAngleRad->setDoubleValue(_sun_angle);
}