1 // cloud.cxx -- 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 program is distributed in the hope that it will be useful, but
8 // WITHOUT ANY WARRANTY; without even the implied warranty of
9 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
10 // General Public License for more details.
12 // You should have received a copy of the GNU General Public License
13 // along with this program; if not, write to the Free Software
14 // Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
19 #include <simgear/compiler.h>
27 #include <simgear/math/point3d.hxx>
28 #include <simgear/math/polar3d.hxx>
29 #include <simgear/math/sg_random.h>
30 #include <simgear/debug/logstream.hxx>
31 #include <simgear/misc/sg_path.hxx>
36 SGCloudLayer::layer_states[SGCloudLayer::SG_MAX_CLOUD_TYPES];
40 SGCloudLayer::SGCloudLayer( const string &tex_path )
41 : layer_root(new ssgRoot),
42 layer_transform(new ssgTransform),
44 texture_path(tex_path),
49 layer_type(SG_CLOUD_CLEAR)
51 layer_root->addKid(layer_transform);
56 SGCloudLayer::~SGCloudLayer()
58 delete layer_root; // deletes layer_transform and layer as well
62 SGCloudLayer::getSpan_m () const
68 SGCloudLayer::setSpan_m (float span_m)
70 if (span_m != layer_span) {
77 SGCloudLayer::getElevation_m () const
83 SGCloudLayer::setElevation_m (float elevation_m)
85 layer_asl = elevation_m;
89 SGCloudLayer::getThickness_m () const
91 return layer_thickness;
95 SGCloudLayer::setThickness_m (float thickness_m)
97 layer_thickness = thickness_m;
101 SGCloudLayer::getTransition_m () const
103 return layer_transition;
107 SGCloudLayer::setTransition_m (float transition_m)
109 layer_transition = transition_m;
113 SGCloudLayer::getType () const
119 SGCloudLayer::setType (Type type)
121 if (type != layer_type) {
128 // build the cloud object
130 SGCloudLayer::rebuild()
132 // Initialize states and sizes if necessary.
133 if (layer_states[0] == 0) {
136 cloud_path.set(texture_path.str());
137 cloud_path.append("overcast.rgb");
138 layer_states[SG_CLOUD_OVERCAST] = SGCloudMakeState(cloud_path.str());
140 cloud_path.set(texture_path.str());
141 cloud_path.append("mostlycloudy.rgba");
142 layer_states[SG_CLOUD_MOSTLY_CLOUDY] =
143 SGCloudMakeState(cloud_path.str());
145 cloud_path.set(texture_path.str());
146 cloud_path.append("mostlysunny.rgba");
147 layer_states[SG_CLOUD_MOSTLY_SUNNY] = SGCloudMakeState(cloud_path.str());
149 cloud_path.set(texture_path.str());
150 cloud_path.append("cirrus.rgba");
151 layer_states[SG_CLOUD_CIRRUS] = SGCloudMakeState(cloud_path.str());
153 layer_states[SG_CLOUD_CLEAR] = 0;
158 last_lon = last_lat = -999.0f;
160 cl = new ssgColourArray( 4 );
161 vl = new ssgVertexArray( 4 );
162 tl = new ssgTexCoordArray( 4 );
164 // build the cloud layer
168 sgSetVec4( color, 1.0f, 1.0f, 1.0f, 1.0f );
170 sgSetVec3( vertex, -layer_span, -layer_span, 0.0f );
172 sgSetVec2( base, sg_random(), sg_random() );
173 sgSetVec2( tc, base[0], base[1] );
178 sgSetVec3( vertex, layer_span, -layer_span, 0.0f );
179 sgSetVec2( tc, base[0] + layer_span / scale, base[1] );
184 sgSetVec3( vertex, -layer_span, layer_span, 0.0f );
185 sgSetVec2( tc, base[0], base[1] + layer_span / scale );
190 sgSetVec3( vertex, layer_span, layer_span, 0.0f );
191 sgSetVec2( tc, base[0] + layer_span / scale, base[1] + layer_span / scale );
197 layer_transform->removeKid(layer); // automatic delete
198 layer = new ssgVtxTable ( GL_TRIANGLE_STRIP, vl, NULL, tl, cl );
199 if (layer_states[layer_type] != 0)
200 layer->setState( layer_states[layer_type] );
202 // force a repaint of the moon colors with arbitrary defaults
205 // moon_transform->addKid( halo );
206 layer_transform->addKid( layer );
210 // repaint the cloud layer colors
211 bool SGCloudLayer::repaint( sgVec3 fog_color ) {
214 for ( int i = 0; i < 4; ++i ) {
215 color = cl->get( i );
216 sgCopyVec4( color, fog_color );
223 // reposition the cloud layer at the specified origin and orientation
224 // lon specifies a rotation about the Z axis
225 // lat specifies a rotation about the new Y axis
226 // spin specifies a rotation about the new Z axis (and orients the
227 // sunrise/set effects
228 bool SGCloudLayer::reposition( sgVec3 p, sgVec3 up, double lon, double lat,
234 // combine p and asl (meters) to get translation offset
236 sgCopyVec3( asl_offset, up );
237 sgNormalizeVec3( asl_offset );
238 if ( alt <= layer_asl ) {
239 sgScaleVec3( asl_offset, layer_asl );
241 sgScaleVec3( asl_offset, layer_asl + layer_thickness );
243 // cout << "asl_offset = " << asl_offset[0] << "," << asl_offset[1]
244 // << "," << asl_offset[2] << endl;
245 sgAddVec3( asl_offset, p );
246 // cout << " asl_offset = " << asl_offset[0] << "," << asl_offset[1]
247 // << "," << asl_offset[2] << endl;
249 // Translate to zero elevation
250 // Point3D zero_elev = current_view.get_cur_zero_elev();
251 // xglTranslatef( zero_elev.x(), zero_elev.y(), zero_elev.z() );
252 sgMakeTransMat4( T1, asl_offset );
254 // printf(" Translated to %.2f %.2f %.2f\n",
255 // zero_elev.x, zero_elev.y, zero_elev.z );
257 // Rotate to proper orientation
258 // printf(" lon = %.2f lat = %.2f\n",
259 // lon * SGD_RADIANS_TO_DEGREES,
260 // lat * SGD_RADIANS_TO_DEGREES);
261 // xglRotatef( lon * SGD_RADIANS_TO_DEGREES, 0.0, 0.0, 1.0 );
262 sgSetVec3( axis, 0.0, 0.0, 1.0 );
263 sgMakeRotMat4( LON, lon * SGD_RADIANS_TO_DEGREES, axis );
265 // xglRotatef( 90.0 - f->get_Latitude() * SGD_RADIANS_TO_DEGREES,
267 sgSetVec3( axis, 0.0, 1.0, 0.0 );
268 sgMakeRotMat4( LAT, 90.0 - lat * SGD_RADIANS_TO_DEGREES, axis );
272 sgCopyMat4( TRANSFORM, T1 );
273 sgPreMultMat4( TRANSFORM, LON );
274 sgPreMultMat4( TRANSFORM, LAT );
277 sgSetCoord( &layerpos, TRANSFORM );
279 layer_transform->setTransform( &layerpos );
281 // now calculate update texture coordinates
282 if ( last_lon < -900 ) {
287 if ( lon != last_lon || lat != last_lat ) {
288 Point3D start( last_lon, last_lat, 0.0 );
289 Point3D dest( lon, lat, 0.0 );
291 calc_gc_course_dist( dest, start, &course, &dist );
292 // cout << "course = " << course << ", dist = " << dist << endl;
294 double xoff = cos( course ) * dist / (2 * scale);
295 double yoff = sin( course ) * dist / (2 * scale);
297 // cout << "xoff = " << xoff << ", yoff = " << yoff << endl;
304 // the while loops can lead to *long* pauses if base[0] comes
305 // with a bogus value.
306 // while ( base[0] > 1.0 ) { base[0] -= 1.0; }
307 // while ( base[0] < 0.0 ) { base[0] += 1.0; }
308 if ( base[0] > -10.0 && base[0] < 10.0 ) {
309 base[0] -= (int)base[0];
312 SG_LOG(SG_ASTRO, SG_DEBUG,
313 "Error: base = " << base[0] << "," << base[1]);
317 // the while loops can lead to *long* pauses if base[0] comes
318 // with a bogus value.
319 // while ( base[1] > 1.0 ) { base[1] -= 1.0; }
320 // while ( base[1] < 0.0 ) { base[1] += 1.0; }
321 if ( base[1] > -10.0 && base[1] < 10.0 ) {
322 base[1] -= (int)base[1];
325 SG_LOG(SG_ASTRO, SG_ALERT,
326 "Error: base = " << base[0] << "," << base[1]);
329 // cout << "base = " << base[0] << "," << base[1] << endl;
332 sgSetVec2( tc, base[0] + layer_span / scale, base[1] );
335 sgSetVec2( tc, base[0], base[1] + layer_span / scale );
338 sgSetVec2( tc, base[0] + layer_span / scale, base[1] + layer_span / scale );
348 void SGCloudLayer::draw() {
349 if (layer_type != SG_CLOUD_CLEAR)
350 ssgCullAndDraw( layer_root );
354 // make an ssgSimpleState for a cloud layer given the named texture
355 ssgSimpleState *SGCloudMakeState( const string &path ) {
356 ssgSimpleState *state = new ssgSimpleState();
358 state->setTexture( (char *)path.c_str() );
359 state->setShadeModel( GL_SMOOTH );
360 state->disable( GL_LIGHTING );
361 state->disable( GL_CULL_FACE );
362 state->enable( GL_TEXTURE_2D );
363 state->enable( GL_COLOR_MATERIAL );
364 state->setColourMaterial( GL_AMBIENT_AND_DIFFUSE );
365 state->setMaterial( GL_EMISSION, 0, 0, 0, 1 );
366 state->setMaterial( GL_SPECULAR, 0, 0, 0, 1 );
367 state->enable( GL_BLEND );
368 state->enable( GL_ALPHA_TEST );
369 state->setAlphaClamp( 0.01 );