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),
47 texture_path(tex_path),
51 layer_transition(0.0),
52 layer_type(SG_CLOUD_CLEAR),
57 for ( int i = 0; i < SG_MAX_CLOUD_TYPES; ++i ) {
58 layer_states[i] = NULL;
60 layer_root->addKid(layer_transform);
65 SGCloudLayer::~SGCloudLayer()
67 delete layer_root; // deletes layer_transform and layer as well
71 SGCloudLayer::getSpan_m () const
77 SGCloudLayer::setSpan_m (float span_m)
79 if (span_m != layer_span) {
86 SGCloudLayer::getElevation_m () const
92 SGCloudLayer::setElevation_m (float elevation_m)
94 layer_asl = elevation_m;
98 SGCloudLayer::getThickness_m () const
100 return layer_thickness;
104 SGCloudLayer::setThickness_m (float thickness_m)
106 layer_thickness = thickness_m;
110 SGCloudLayer::getTransition_m () const
112 return layer_transition;
116 SGCloudLayer::setTransition_m (float transition_m)
118 layer_transition = transition_m;
122 SGCloudLayer::getType () const
128 SGCloudLayer::setType (Type type)
130 if (type != layer_type) {
137 // build the cloud object
139 SGCloudLayer::rebuild()
141 // Initialize states and sizes if necessary.
142 if ( layer_states[0] == NULL ) {
145 cloud_path.set(texture_path.str());
146 cloud_path.append("overcast.rgb");
147 layer_states[SG_CLOUD_OVERCAST] = SGCloudMakeState(cloud_path.str());
149 cloud_path.set(texture_path.str());
150 cloud_path.append("mostlycloudy.rgba");
151 layer_states[SG_CLOUD_MOSTLY_CLOUDY]
152 = SGCloudMakeState(cloud_path.str());
154 cloud_path.set(texture_path.str());
155 cloud_path.append("mostlysunny.rgba");
156 layer_states[SG_CLOUD_MOSTLY_SUNNY]
157 = SGCloudMakeState(cloud_path.str());
159 cloud_path.set(texture_path.str());
160 cloud_path.append("cirrus.rgba");
161 layer_states[SG_CLOUD_CIRRUS] = SGCloudMakeState(cloud_path.str());
163 layer_states[SG_CLOUD_CLEAR] = 0;
168 last_lon = last_lat = -999.0f;
170 if ( layer != NULL ) {
171 layer_transform->removeKid(layer); // automatic delete
174 cl = new ssgColourArray( 4 );
175 vl = new ssgVertexArray( 4 );
176 tl = new ssgTexCoordArray( 4 );
178 // build the cloud layer
182 sgSetVec4( color, 1.0f, 1.0f, 1.0f, 1.0f );
184 sgSetVec3( vertex, -layer_span, -layer_span, 0.0f );
186 sgSetVec2( base, sg_random(), sg_random() );
187 sgSetVec2( tc, base[0], base[1] );
192 sgSetVec3( vertex, layer_span, -layer_span, 0.0f );
193 sgSetVec2( tc, base[0] + layer_span / scale, base[1] );
198 sgSetVec3( vertex, -layer_span, layer_span, 0.0f );
199 sgSetVec2( tc, base[0], base[1] + layer_span / scale );
204 sgSetVec3( vertex, layer_span, layer_span, 0.0f );
205 sgSetVec2( tc, base[0] + layer_span / scale, base[1] + layer_span / scale );
210 layer = new ssgVtxTable ( GL_TRIANGLE_STRIP, vl, NULL, tl, cl );
211 layer_transform->addKid( layer );
212 if ( layer_states[layer_type] != NULL ) {
213 layer->setState( layer_states[layer_type] );
216 // force a repaint of the sky colors with arbitrary defaults
222 // repaint the cloud layer colors
223 bool SGCloudLayer::repaint( sgVec3 fog_color ) {
226 for ( int i = 0; i < 4; ++i ) {
227 color = cl->get( i );
228 sgCopyVec4( color, fog_color );
235 // reposition the cloud layer at the specified origin and orientation
236 // lon specifies a rotation about the Z axis
237 // lat specifies a rotation about the new Y axis
238 // spin specifies a rotation about the new Z axis (and orients the
239 // sunrise/set effects
240 bool SGCloudLayer::reposition( sgVec3 p, sgVec3 up, double lon, double lat,
246 // combine p and asl (meters) to get translation offset
248 sgCopyVec3( asl_offset, up );
249 sgNormalizeVec3( asl_offset );
250 if ( alt <= layer_asl ) {
251 sgScaleVec3( asl_offset, layer_asl );
253 sgScaleVec3( asl_offset, layer_asl + layer_thickness );
255 // cout << "asl_offset = " << asl_offset[0] << "," << asl_offset[1]
256 // << "," << asl_offset[2] << endl;
257 sgAddVec3( asl_offset, p );
258 // cout << " asl_offset = " << asl_offset[0] << "," << asl_offset[1]
259 // << "," << asl_offset[2] << endl;
261 // Translate to zero elevation
262 // Point3D zero_elev = current_view.get_cur_zero_elev();
263 // xglTranslatef( zero_elev.x(), zero_elev.y(), zero_elev.z() );
264 sgMakeTransMat4( T1, asl_offset );
266 // printf(" Translated to %.2f %.2f %.2f\n",
267 // zero_elev.x, zero_elev.y, zero_elev.z );
269 // Rotate to proper orientation
270 // printf(" lon = %.2f lat = %.2f\n",
271 // lon * SGD_RADIANS_TO_DEGREES,
272 // lat * SGD_RADIANS_TO_DEGREES);
273 // xglRotatef( lon * SGD_RADIANS_TO_DEGREES, 0.0, 0.0, 1.0 );
274 sgSetVec3( axis, 0.0, 0.0, 1.0 );
275 sgMakeRotMat4( LON, lon * SGD_RADIANS_TO_DEGREES, axis );
277 // xglRotatef( 90.0 - f->get_Latitude() * SGD_RADIANS_TO_DEGREES,
279 sgSetVec3( axis, 0.0, 1.0, 0.0 );
280 sgMakeRotMat4( LAT, 90.0 - lat * SGD_RADIANS_TO_DEGREES, axis );
284 sgCopyMat4( TRANSFORM, T1 );
285 sgPreMultMat4( TRANSFORM, LON );
286 sgPreMultMat4( TRANSFORM, LAT );
289 sgSetCoord( &layerpos, TRANSFORM );
291 layer_transform->setTransform( &layerpos );
293 // now calculate update texture coordinates
294 if ( last_lon < -900 ) {
299 if ( lon != last_lon || lat != last_lat ) {
300 Point3D start( last_lon, last_lat, 0.0 );
301 Point3D dest( lon, lat, 0.0 );
303 calc_gc_course_dist( dest, start, &course, &dist );
304 // cout << "course = " << course << ", dist = " << dist << endl;
306 double xoff = cos( course ) * dist / (2 * scale);
307 double yoff = sin( course ) * dist / (2 * scale);
309 // cout << "xoff = " << xoff << ", yoff = " << yoff << endl;
316 // the while loops can lead to *long* pauses if base[0] comes
317 // with a bogus value.
318 // while ( base[0] > 1.0 ) { base[0] -= 1.0; }
319 // while ( base[0] < 0.0 ) { base[0] += 1.0; }
320 if ( base[0] > -10.0 && base[0] < 10.0 ) {
321 base[0] -= (int)base[0];
324 SG_LOG(SG_ASTRO, SG_DEBUG,
325 "Error: base = " << base[0] << "," << base[1]);
329 // the while loops can lead to *long* pauses if base[0] comes
330 // with a bogus value.
331 // while ( base[1] > 1.0 ) { base[1] -= 1.0; }
332 // while ( base[1] < 0.0 ) { base[1] += 1.0; }
333 if ( base[1] > -10.0 && base[1] < 10.0 ) {
334 base[1] -= (int)base[1];
337 SG_LOG(SG_ASTRO, SG_ALERT,
338 "Error: base = " << base[0] << "," << base[1]);
341 // cout << "base = " << base[0] << "," << base[1] << endl;
344 sgSetVec2( tc, base[0] + layer_span / scale, base[1] );
347 sgSetVec2( tc, base[0], base[1] + layer_span / scale );
350 sgSetVec2( tc, base[0] + layer_span / scale, base[1] + layer_span / scale );
360 void SGCloudLayer::draw() {
361 if ( layer_type != SG_CLOUD_CLEAR ) {
362 ssgCullAndDraw( layer_root );
367 // make an ssgSimpleState for a cloud layer given the named texture
368 ssgSimpleState *SGCloudMakeState( const string &path ) {
369 ssgSimpleState *state = new ssgSimpleState();
371 state->setTexture( (char *)path.c_str() );
372 state->setShadeModel( GL_SMOOTH );
373 state->disable( GL_LIGHTING );
374 state->disable( GL_CULL_FACE );
375 state->enable( GL_TEXTURE_2D );
376 state->enable( GL_COLOR_MATERIAL );
377 state->setColourMaterial( GL_AMBIENT_AND_DIFFUSE );
378 state->setMaterial( GL_EMISSION, 0, 0, 0, 1 );
379 state->setMaterial( GL_SPECULAR, 0, 0, 0, 1 );
380 state->enable( GL_BLEND );
381 state->enable( GL_ALPHA_TEST );
382 state->setAlphaClamp( 0.01 );
384 // ref() the state so it doesn't get deleted if the last layer of
385 // it's type is deleted.