1 // cloud.hxx -- model a single cloud layer
3 // Written by Curtis Olson, started June 2000.
5 // Copyright (C) 2000 Curtis L. Olson - curt@flightgear.org
7 // This library is free software; you can redistribute it and/or
8 // modify it under the terms of the GNU Library General Public
9 // License as published by the Free Software Foundation; either
10 // version 2 of the License, or (at your option) any later version.
12 // This library is distributed in the hope that it will be useful,
13 // but WITHOUT ANY WARRANTY; without even the implied warranty of
14 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 // Library General Public License for more details.
17 // You should have received a copy of the GNU Library General Public
18 // License along with this library; if not, write to the
19 // Free Software Foundation, Inc., 59 Temple Place - Suite 330,
20 // Boston, MA 02111-1307, USA.
25 #ifndef _SG_CLOUD_HXX_
26 #define _SG_CLOUD_HXX_
28 #include <simgear/compiler.h>
36 #define SG_MAX_CLOUD_TYPES 4 // change this if we add/remove cloud
37 // types en the enum below
40 SG_CLOUD_OVERCAST = 0,
41 SG_CLOUD_MOSTLY_CLOUDY,
42 SG_CLOUD_MOSTLY_SUNNY,
52 ssgTransform *layer_transform;
53 ssgSimpleState *layer_state;
59 // height above sea level (meters)
61 float layer_thickness;
62 float layer_transition;
66 // for handling texture coordinates to simulate cloud movement
67 // from winds, and to simulate the clouds being tied to ground
68 // position, not view position
70 double last_lon, last_lat;
78 ~SGCloudLayer( void );
80 // build the cloud object
81 void build( double size, double asl, double thickness,
82 double transition, ssgSimpleState *state );
84 // repaint the cloud colors based on current value of sun_angle,
85 // sky, and fog colors. This updates the color arrays for
87 // sun angle in degrees relative to verticle
88 // 0 degrees = high noon
89 // 90 degrees = sun rise/set
90 // 180 degrees = darkest midnight
91 bool repaint( sgVec3 fog_color );
93 // reposition the cloud layer at the specified origin and
95 // lon specifies a rotation about the Z axis
96 // lat specifies a rotation about the new Y axis
97 // spin specifies a rotation about the new Z axis (and orients the
98 // sunrise/set effects
99 bool reposition( sgVec3 p, sgVec3 up, double lon, double lat, double alt );
101 // draw the cloud layer
104 inline float get_asl() const { return layer_asl; }
105 inline float get_thickness() const { return layer_thickness; }
106 inline float get_transition() const { return layer_transition; }
110 // make an ssgSimpleState for a cloud layer given the named texture
111 ssgSimpleState *SGCloudMakeState( const string &path );
114 #endif // _SG_CLOUD_HXX_