#include

#include "light.hxx" #include "sunpos.hxx" extern SGSky *thesky; // FIXME: from main.cxx fgLIGHT cur_light_params; // Constructor fgLIGHT::fgLIGHT( void ) { } // initialize lighting tables void fgLIGHT::Init( void ) { SG_LOG( SG_EVENT, SG_INFO, "Initializing Lighting interpolation tables." ); // build the path name to the ambient lookup table SGPath path( globals->get_fg_root() ); SGPath ambient = path; ambient.append( "Lighting/ambient" ); SGPath diffuse = path; diffuse.append( "Lighting/diffuse" ); SGPath specular = path; specular.append( "Lighting/specular" ); SGPath sky = path; sky.append( "Lighting/sky" ); // initialize ambient table ambient_tbl = new SGInterpTable( ambient.str() ); // initialize diffuse table diffuse_tbl = new SGInterpTable( diffuse.str() ); // initialize diffuse table specular_tbl = new SGInterpTable( specular.str() ); // initialize sky table sky_tbl = new SGInterpTable( sky.str() ); } // update lighting parameters based on current sun position void fgLIGHT::Update( void ) { // if the 4th field is 0.0, this specifies a direction ... GLfloat white[4] = { 1.0, 1.0, 1.0, 1.0 }; // base sky color GLfloat base_sky_color[4] = { 0.39, 0.50, 0.74, 1.0 }; // base fog color GLfloat base_fog_color[4] = { 0.84, 0.87, 1.0, 1.0 }; float deg, ambient, diffuse, specular, sky_brightness; SG_LOG( SG_EVENT, SG_INFO, "Updating light parameters." ); // calculate lighting parameters based on sun's relative angle to // local up deg = sun_angle * SGD_RADIANS_TO_DEGREES; SG_LOG( SG_EVENT, SG_INFO, " Sun angle = " << deg ); ambient = ambient_tbl->interpolate( deg ); diffuse = diffuse_tbl->interpolate( deg ); specular = specular_tbl->interpolate( deg ); sky_brightness = sky_tbl->interpolate( deg ); SG_LOG( SG_EVENT, SG_INFO, " ambient = " << ambient << " diffuse = " << diffuse << " specular = " << specular << " sky = " << sky_brightness ); // sky_brightness = 0.15; // used to force a dark sky (when testing) // if ( ambient < 0.02 ) { ambient = 0.02; } // if ( diffuse < 0.0 ) { diffuse = 0.0; } // if ( sky_brightness < 0.1 ) { sky_brightness = 0.1; } scene_ambient[0] = white[0] * ambient; scene_ambient[1] = white[1] * ambient; scene_ambient[2] = white[2] * ambient; scene_ambient[3] = 1.0; scene_diffuse[0] = white[0] * diffuse; scene_diffuse[1] = white[1] * diffuse; scene_diffuse[2] = white[2] * diffuse; scene_diffuse[3] = 1.0; scene_specular[0] = white[0] * specular; scene_specular[1] = white[1] * specular; scene_specular[2] = white[2] * specular; scene_specular[3] = 1.0; // 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[3] = base_sky_color[3]; gamma_correct_rgb( sky_color ); // set cloud and fog color cloud_color[0] = fog_color[0] = base_fog_color[0] * sky_brightness; cloud_color[1] = fog_color[1] = base_fog_color[1] * sky_brightness; cloud_color[2] = fog_color[2] = base_fog_color[2] * sky_brightness; cloud_color[3] = fog_color[3] = base_fog_color[3]; gamma_correct_rgb( fog_color ); // adjust the cloud colors for sunrise/sunset effects (darken them) if (sun_angle > 1.0) { float sun2 = pow(sun_angle, 0.5); cloud_color[0] /= sun2; cloud_color[1] /= sun2; cloud_color[2] /= sun2; } gamma_correct_rgb( cloud_color ); } // calculate fog color adjusted for sunrise/sunset effects void fgLIGHT::UpdateAdjFog( void ) { double heading = globals->get_current_view()->getHeading_deg() * SGD_DEGREES_TO_RADIANS; double heading_offset = globals->get_current_view()->getHeadingOffset_deg() * SGD_DEGREES_TO_RADIANS; SG_LOG( SG_EVENT, SG_DEBUG, "Updating adjusted fog parameters." ); // set fog color (we'll try to match the sunset color in the // direction we are looking // Do some sanity checking ... if ( sun_rotation < -2.0 * SGD_2PI || sun_rotation > 2.0 * SGD_2PI ) { SG_LOG( SG_EVENT, SG_ALERT, "Sun rotation bad = " << sun_rotation ); exit(-1); } if ( heading < -2.0 * SGD_2PI || heading > 2.0 * SGD_2PI ) { SG_LOG( SG_EVENT, SG_ALERT, "Heading rotation bad = " << heading ); exit(-1); } if ( heading_offset < -2.0 * SGD_2PI || heading_offset > 2.0 * SGD_2PI ) { SG_LOG( SG_EVENT, SG_ALERT, "Heading offset bad = " << heading_offset ); exit(-1); } double rotation; // first determine the difference between our view angle and local // direction to the sun rotation = -(sun_rotation + SGD_PI) - heading + heading_offset; while ( rotation < 0 ) { rotation += SGD_2PI; } while ( rotation > SGD_2PI ) { rotation -= SGD_2PI; } // revert to unmodified values before usign them. // float *sun_color = thesky->get_sun_color(); gamma_restore_rgb( fog_color ); gamma_restore_rgb( cloud_color ); // Calculate the fog color in the direction of the sun for // sunrise/sunset effects. // float s_red = (fog_color[0] + 2 * pow(sun_color[0], 2)) / 3; float s_green = (fog_color[1] + 2 * pow(sun_color[1], 2)) / 3; float s_blue = (fog_color[2] + 2 * sun_color[2]) / 3; // interpolate beween the sunrise/sunset color and the color // at the opposite direction of this effect. Take in account // the current visibility. // float av = thesky->get_visibility(); if (av > 45000) av = 45000; float avf = 0.87 - (45000 - av) / 83333.33; float sif = 0.5 - cos(sun_angle*2)/2; float rf1 = fabs((rotation - SGD_PI) / SGD_PI); // 0.0 .. 1.0 float rf2 = avf * pow(rf1 * rf1, 1/sif); float rf3 = 0.94 - rf2; 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; gamma_correct_rgb( adj_fog_color ); // make sure the colors have their original value before they are being // used by the rest of the program. // gamma_correct_rgb( fog_color ); gamma_correct_rgb( cloud_color ); } // Destructor fgLIGHT::~fgLIGHT( void ) { }