1
0
Fork 0
flightgear/Simulator/Astro/sky.cxx
1999-04-06 23:37:07 +00:00

362 lines
11 KiB
C++

// sky.cxx -- model sky with an upside down "bowl"
//
// Written by Curtis Olson, started December 1997.
//
// Copyright (C) 1997 Curtis L. Olson - curt@infoplane.com
//
// 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.
//
// $Id$
#ifdef HAVE_CONFIG_H
# include <config.h>
#endif
#ifdef HAVE_WINDOWS_H
# include <windows.h>
#endif
#include <math.h>
#include <GL/glut.h>
#include <XGL/xgl.h>
#include <Aircraft/aircraft.hxx>
#include <Debug/logstream.hxx>
#include <FDM/flight.hxx>
#include <Include/fg_constants.h>
#include <Main/views.hxx>
#include <Math/fg_random.h>
#include <Time/event.hxx>
#include <Time/fg_time.hxx>
#include "sky.hxx"
// in meters of course
#define CENTER_ELEV 25000.0
#define INNER_RADIUS 50000.0
#define INNER_ELEV 20000.0
#define MIDDLE_RADIUS 70000.0
#define MIDDLE_ELEV 8000.0
#define OUTER_RADIUS 80000.0
#define OUTER_ELEV 0.0
#define BOTTOM_RADIUS 50000.0
#define BOTTOM_ELEV -2000.0
static float inner_vertex[12][3];
static float middle_vertex[12][3];
static float outer_vertex[12][3];
static float bottom_vertex[12][3];
static float inner_color[12][4];
static float middle_color[12][4];
static float outer_color[12][4];
// Calculate the sky structure vertices
void fgSkyVerticesInit( void ) {
float theta;
int i;
FG_LOG(FG_ASTRO, FG_INFO, " Generating the sky dome vertices.");
for ( i = 0; i < 12; i++ ) {
theta = (i * 30.0) * DEG_TO_RAD;
inner_vertex[i][0] = cos(theta) * INNER_RADIUS;
inner_vertex[i][1] = sin(theta) * INNER_RADIUS;
inner_vertex[i][2] = INNER_ELEV;
// printf(" %.2f %.2f\n", cos(theta) * INNER_RADIUS,
// sin(theta) * INNER_RADIUS);
middle_vertex[i][0] = cos((double)theta) * MIDDLE_RADIUS;
middle_vertex[i][1] = sin((double)theta) * MIDDLE_RADIUS;
middle_vertex[i][2] = MIDDLE_ELEV;
outer_vertex[i][0] = cos((double)theta) * OUTER_RADIUS;
outer_vertex[i][1] = sin((double)theta) * OUTER_RADIUS;
outer_vertex[i][2] = OUTER_ELEV;
bottom_vertex[i][0] = cos((double)theta) * BOTTOM_RADIUS;
bottom_vertex[i][1] = sin((double)theta) * BOTTOM_RADIUS;
bottom_vertex[i][2] = BOTTOM_ELEV;
}
}
// (Re)calculate the sky colors at each vertex
void fgSkyColorsInit( void ) {
fgLIGHT *l;
double sun_angle, diff;
double outer_param[3], outer_amt[3], outer_diff[3];
double middle_param[3], middle_amt[3], middle_diff[3];
int i, j;
l = &cur_light_params;
FG_LOG( FG_ASTRO, FG_INFO,
" Generating the sky colors for each vertex." );
// setup for the possibility of sunset effects
sun_angle = l->sun_angle * RAD_TO_DEG;
// fgPrintf( FG_ASTRO, FG_INFO,
// " Sun angle in degrees = %.2f\n", sun_angle);
if ( (sun_angle > 80.0) && (sun_angle < 100.0) ) {
// 0.0 - 0.4
outer_param[0] = (10.0 - fabs(90.0 - sun_angle)) / 20.0;
outer_param[1] = (10.0 - fabs(90.0 - sun_angle)) / 40.0;
outer_param[2] = -(10.0 - fabs(90.0 - sun_angle)) / 30.0;
// outer_param[2] = 0.0;
middle_param[0] = (10.0 - fabs(90.0 - sun_angle)) / 40.0;
middle_param[1] = (10.0 - fabs(90.0 - sun_angle)) / 80.0;
middle_param[2] = 0.0;
outer_diff[0] = outer_param[0] / 6.0;
outer_diff[1] = outer_param[1] / 6.0;
outer_diff[2] = outer_param[2] / 6.0;
middle_diff[0] = middle_param[0] / 6.0;
middle_diff[1] = middle_param[1] / 6.0;
middle_diff[2] = middle_param[2] / 6.0;
} else {
outer_param[0] = outer_param[1] = outer_param[2] = 0.0;
middle_param[0] = middle_param[1] = middle_param[2] = 0.0;
outer_diff[0] = outer_diff[1] = outer_diff[2] = 0.0;
middle_diff[0] = middle_diff[1] = middle_diff[2] = 0.0;
}
// printf(" outer_red_param = %.2f outer_red_diff = %.2f\n",
// outer_red_param, outer_red_diff);
// calculate transition colors between sky and fog
for ( j = 0; j < 3; j++ ) {
outer_amt[j] = outer_param[j];
middle_amt[j] = middle_param[j];
}
for ( i = 0; i < 6; i++ ) {
for ( j = 0; j < 3; j++ ) {
diff = l->sky_color[j] - l->fog_color[j];
// printf("sky = %.2f fog = %.2f diff = %.2f\n",
// l->sky_color[j], l->fog_color[j], diff);
inner_color[i][j] = l->sky_color[j] - diff * 0.3;
middle_color[i][j] = l->sky_color[j] - diff * 0.9 + middle_amt[j];
outer_color[i][j] = l->fog_color[j] + outer_amt[j];
if ( inner_color[i][j] > 1.00 ) { inner_color[i][j] = 1.00; }
if ( inner_color[i][j] < 0.10 ) { inner_color[i][j] = 0.10; }
if ( middle_color[i][j] > 1.00 ) { middle_color[i][j] = 1.00; }
if ( middle_color[i][j] < 0.10 ) { middle_color[i][j] = 0.10; }
if ( outer_color[i][j] > 1.00 ) { outer_color[i][j] = 1.00; }
if ( outer_color[i][j] < 0.10 ) { outer_color[i][j] = 0.10; }
}
inner_color[i][3] = middle_color[i][3] = outer_color[i][3] =
l->sky_color[3];
for ( j = 0; j < 3; j++ ) {
outer_amt[j] -= outer_diff[j];
middle_amt[j] -= middle_diff[j];
}
/*
printf("inner_color[%d] = %.2f %.2f %.2f %.2f\n", i, inner_color[i][0],
inner_color[i][1], inner_color[i][2], inner_color[i][3]);
printf("middle_color[%d] = %.2f %.2f %.2f %.2f\n", i,
middle_color[i][0], middle_color[i][1], middle_color[i][2],
middle_color[i][3]);
printf("outer_color[%d] = %.2f %.2f %.2f %.2f\n", i,
outer_color[i][0], outer_color[i][1], outer_color[i][2],
outer_color[i][3]);
*/
}
for ( j = 0; j < 3; j++ ) {
outer_amt[j] = 0.0;
middle_amt[j] = 0.0;
}
for ( i = 6; i < 12; i++ ) {
for ( j = 0; j < 3; j++ ) {
diff = l->sky_color[j] - l->fog_color[j];
// printf("sky = %.2f fog = %.2f diff = %.2f\n",
// l->sky_color[j], l->fog_color[j], diff);
inner_color[i][j] = l->sky_color[j] - diff * 0.3;
middle_color[i][j] = l->sky_color[j] - diff * 0.9 + middle_amt[j];
outer_color[i][j] = l->fog_color[j] + outer_amt[j];
if ( inner_color[i][j] > 1.00 ) { inner_color[i][j] = 1.00; }
if ( inner_color[i][j] < 0.10 ) { inner_color[i][j] = 0.10; }
if ( middle_color[i][j] > 1.00 ) { middle_color[i][j] = 1.00; }
if ( middle_color[i][j] < 0.10 ) { middle_color[i][j] = 0.10; }
if ( outer_color[i][j] > 1.00 ) { outer_color[i][j] = 1.00; }
if ( outer_color[i][j] < 0.15 ) { outer_color[i][j] = 0.15; }
}
inner_color[i][3] = middle_color[i][3] = outer_color[i][3] =
l->sky_color[3];
for ( j = 0; j < 3; j++ ) {
outer_amt[j] += outer_diff[j];
middle_amt[j] += middle_diff[j];
}
/*
printf("inner_color[%d] = %.2f %.2f %.2f %.2f\n", i, inner_color[i][0],
inner_color[i][1], inner_color[i][2], inner_color[i][3]);
printf("middle_color[%d] = %.2f %.2f %.2f %.2f\n", i,
middle_color[i][0], middle_color[i][1], middle_color[i][2],
middle_color[i][3]);
printf("outer_color[%d] = %.2f %.2f %.2f %.2f\n", i,
outer_color[i][0], outer_color[i][1], outer_color[i][2],
outer_color[i][3]);
*/
}
}
// Initialize the sky structure and colors
void fgSkyInit( void ) {
FG_LOG( FG_ASTRO, FG_INFO, "Initializing the sky" );
fgSkyVerticesInit();
// regester fgSkyColorsInit() as an event to be run periodically
global_events.Register( "fgSkyColorsInit()", fgSkyColorsInit,
fgEVENT::FG_EVENT_READY, 30000);
}
// Draw the Sky
void fgSkyRender( void ) {
FGInterface *f;
fgLIGHT *l;
float inner_color[4];
float middle_color[4];
float outer_color[4];
double diff;
int i;
f = current_aircraft.fdm_state;
l = &cur_light_params;
// printf("Rendering the sky.\n");
// calculate the proper colors
for ( i = 0; i < 3; i++ ) {
diff = l->sky_color[i] - l->adj_fog_color[i];
// printf("sky = %.2f fog = %.2f diff = %.2f\n",
// l->sky_color[j], l->adj_fog_color[j], diff);
inner_color[i] = l->sky_color[i] - diff * 0.3;
middle_color[i] = l->sky_color[i] - diff * 0.9;
outer_color[i] = l->adj_fog_color[i];
}
inner_color[3] = middle_color[3] = outer_color[3] = l->adj_fog_color[3];
xglPushMatrix();
// Translate to view position
Point3D zero_elev = current_view.get_cur_zero_elev();
xglTranslatef( zero_elev.x(), zero_elev.y(), zero_elev.z() );
// printf(" Translated to %.2f %.2f %.2f\n",
// zero_elev.x, zero_elev.y, zero_elev.z );
// Rotate to proper orientation
// printf(" lon = %.2f lat = %.2f\n", FG_Longitude * RAD_TO_DEG,
// FG_Latitude * RAD_TO_DEG);
xglRotatef( f->get_Longitude() * RAD_TO_DEG, 0.0, 0.0, 1.0 );
xglRotatef( 90.0 - f->get_Latitude() * RAD_TO_DEG, 0.0, 1.0, 0.0 );
xglRotatef( l->sun_rotation * RAD_TO_DEG, 0.0, 0.0, 1.0 );
// Draw inner/center section of sky*/
xglBegin( GL_TRIANGLE_FAN );
xglColor4fv(l->sky_color);
xglVertex3f(0.0, 0.0, CENTER_ELEV);
for ( i = 11; i >= 0; i-- ) {
xglColor4fv( inner_color );
xglVertex3fv( inner_vertex[i] );
}
xglColor4fv( inner_color );
xglVertex3fv( inner_vertex[11] );
xglEnd();
// Draw the middle ring
xglBegin( GL_TRIANGLE_STRIP );
for ( i = 0; i < 12; i++ ) {
xglColor4fv( middle_color );
// printf("middle_color[%d] = %.2f %.2f %.2f %.2f\n", i,
// middle_color[i][0], middle_color[i][1], middle_color[i][2],
// middle_color[i][3]);
// xglColor4f(1.0, 0.0, 0.0, 1.0);
xglVertex3fv( middle_vertex[i] );
xglColor4fv( inner_color );
// printf("inner_color[%d] = %.2f %.2f %.2f %.2f\n", i,
// inner_color[i][0], inner_color[i][1], inner_color[i][2],
// inner_color[i][3]);
// xglColor4f(0.0, 0.0, 1.0, 1.0);
xglVertex3fv( inner_vertex[i] );
}
xglColor4fv( middle_color );
// xglColor4f(1.0, 0.0, 0.0, 1.0);
xglVertex3fv( middle_vertex[0] );
xglColor4fv( inner_color );
// xglColor4f(0.0, 0.0, 1.0, 1.0);
xglVertex3fv( inner_vertex[0] );
xglEnd();
// Draw the outer ring
xglBegin( GL_TRIANGLE_STRIP );
for ( i = 0; i < 12; i++ ) {
xglColor4fv( outer_color );
xglVertex3fv( outer_vertex[i] );
xglColor4fv( middle_color );
xglVertex3fv( middle_vertex[i] );
}
xglColor4fv( outer_color );
xglVertex3fv( outer_vertex[0] );
xglColor4fv( middle_color );
xglVertex3fv( middle_vertex[0] );
xglEnd();
// Draw the bottom skirt
xglBegin( GL_TRIANGLE_STRIP );
xglColor4fv( outer_color );
for ( i = 0; i < 12; i++ ) {
xglVertex3fv( bottom_vertex[i] );
xglVertex3fv( outer_vertex[i] );
}
xglVertex3fv( bottom_vertex[0] );
xglVertex3fv( outer_vertex[0] );
xglEnd();
xglPopMatrix();
}