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 static ssgSimpleState *layer_states[SGCloudLayer::SG_MAX_CLOUD_COVERAGES];
37 static bool state_initialized = false;
41 SGCloudLayer::SGCloudLayer( const string &tex_path ) :
42 layer_root(new ssgRoot),
43 layer_transform(new ssgTransform),
44 texture_path(tex_path),
48 layer_transition(0.0),
49 layer_coverage(SG_CLOUD_CLEAR),
56 cl[0] = cl[1] = cl[2] = cl[3] = NULL;
57 vl[0] = vl[1] = vl[2] = vl[3] = NULL;
58 tl[0] = tl[1] = tl[2] = tl[3] = NULL;
59 layer[0] = layer[1] = layer[2] = layer[3] = NULL;
61 layer_root->addKid(layer_transform);
66 SGCloudLayer::~SGCloudLayer()
68 delete layer_root; // deletes layer_transform and layer as well
72 SGCloudLayer::getSpan_m () const
78 SGCloudLayer::setSpan_m (float span_m)
80 if (span_m != layer_span) {
87 SGCloudLayer::getElevation_m () const
93 SGCloudLayer::setElevation_m (float elevation_m)
95 layer_asl = elevation_m;
99 SGCloudLayer::getThickness_m () const
101 return layer_thickness;
105 SGCloudLayer::setThickness_m (float thickness_m)
107 layer_thickness = thickness_m;
111 SGCloudLayer::getTransition_m () const
113 return layer_transition;
117 SGCloudLayer::setTransition_m (float transition_m)
119 layer_transition = transition_m;
122 SGCloudLayer::Coverage
123 SGCloudLayer::getCoverage () const
125 return layer_coverage;
129 SGCloudLayer::setCoverage (Coverage coverage)
131 if (coverage != layer_coverage) {
132 layer_coverage = coverage;
138 // build the cloud object
140 SGCloudLayer::rebuild()
142 // Initialize states and sizes if necessary.
143 if ( !state_initialized ) {
144 state_initialized = true;
146 cout << "initializing cloud layers" << endl;
150 cloud_path.set(texture_path.str());
151 cloud_path.append("overcast.rgb");
152 layer_states[SG_CLOUD_OVERCAST] = sgCloudMakeState(cloud_path.str());
154 cloud_path.set(texture_path.str());
155 cloud_path.append("broken.rgba");
156 layer_states[SG_CLOUD_BROKEN]
157 = sgCloudMakeState(cloud_path.str());
159 cloud_path.set(texture_path.str());
160 cloud_path.append("scattered.rgba");
161 layer_states[SG_CLOUD_SCATTERED]
162 = sgCloudMakeState(cloud_path.str());
164 cloud_path.set(texture_path.str());
165 cloud_path.append("few.rgba");
166 layer_states[SG_CLOUD_FEW]
167 = sgCloudMakeState(cloud_path.str());
169 cloud_path.set(texture_path.str());
170 cloud_path.append("cirrus.rgba");
171 layer_states[SG_CLOUD_CIRRUS]
172 = sgCloudMakeState(cloud_path.str());
174 layer_states[SG_CLOUD_CLEAR] = 0;
178 last_lon = last_lat = -999.0f;
181 sgSetVec2( base, sg_random(), sg_random() );
183 // build the cloud layer
188 const float layer_scale = layer_span / scale;
189 const float mpi = SG_PI/4;
191 for (int i = 0; i < 4; i++)
193 if ( layer[i] != NULL ) {
194 layer_transform->removeKid(layer[i]); // automatic delete
197 vl[i] = new ssgVertexArray( 10 );
198 cl[i] = new ssgColourArray( 10 );
199 tl[i] = new ssgTexCoordArray( 10 );
202 sgSetVec3( vertex, layer_span*(i-2)/2, -layer_span,
203 500 * (sin(i*mpi) - 2) );
205 sgSetVec2( tc, base[0] + layer_scale * i/4, base[1] );
207 sgSetVec4( color, 1.0f, 1.0f, 1.0f, (i == 0) ? 0.0f : 0.15f );
210 vl[i]->add( vertex );
213 for (int j = 0; j < 4; j++)
215 sgSetVec3( vertex, layer_span*(i-1)/2, layer_span*(j-2)/2,
216 500 * (sin((i+1)*mpi) + sin(j*mpi) - 2) );
218 sgSetVec2( tc, base[0] + layer_scale * (i+1)/4,
219 base[1] + layer_scale * j/4 );
221 sgSetVec4( color, 1.0f, 1.0f, 1.0f,
222 ( (j == 0) || (i == 3)) ?
223 ( (j == 0) && (i == 3)) ? 0.0f : 0.15f : 1.0f );
226 vl[i]->add( vertex );
230 sgSetVec3( vertex, layer_span*(i-2)/2, layer_span*(j-1)/2,
231 500 * (sin(i*mpi) + sin((j+1)*mpi) - 2) );
233 sgSetVec2( tc, base[0] + layer_scale * i/4,
234 base[1] + layer_scale * (j+1)/4 );
236 sgSetVec4( color, 1.0f, 1.0f, 1.0f,
237 ((j == 3) || (i == 0)) ?
238 ((j == 3) && (i == 0)) ? 0.0f : 0.15f : 1.0f );
240 vl[i]->add( vertex );
244 sgSetVec3( vertex, layer_span*(i-1)/2, layer_span,
245 500 * (sin((i+1)*mpi) - 2) );
247 sgSetVec2( tc, base[0] + layer_scale * (i+1)/4,
248 base[1] + layer_scale );
250 sgSetVec4( color, 1.0f, 1.0f, 1.0f, (i == 3) ? 0.0f : 0.15f );
253 vl[i]->add( vertex );
256 layer[i] = new ssgVtxTable(GL_TRIANGLE_STRIP, vl[i], NULL, tl[i], cl[i]);
257 layer_transform->addKid( layer[i] );
259 if ( layer_states[layer_coverage] != NULL ) {
260 layer[i]->setState( layer_states[layer_coverage] );
264 // force a repaint of the sky colors with arbitrary defaults
270 // repaint the cloud layer colors
271 bool SGCloudLayer::repaint( sgVec3 fog_color ) {
274 for ( int i = 0; i < 4; i++ )
275 for ( int j = 0; j < 10; ++j ) {
276 color = cl[i]->get( j );
277 sgCopyVec3( color, fog_color );
284 // reposition the cloud layer at the specified origin and orientation
285 // lon specifies a rotation about the Z axis
286 // lat specifies a rotation about the new Y axis
287 // spin specifies a rotation about the new Z axis (and orients the
288 // sunrise/set effects
289 bool SGCloudLayer::reposition( sgVec3 p, sgVec3 up, double lon, double lat,
290 double alt, double dt )
295 // combine p and asl (meters) to get translation offset
297 sgCopyVec3( asl_offset, up );
298 sgNormalizeVec3( asl_offset );
299 if ( alt <= layer_asl ) {
300 sgScaleVec3( asl_offset, layer_asl );
302 sgScaleVec3( asl_offset, layer_asl + layer_thickness );
304 // cout << "asl_offset = " << asl_offset[0] << "," << asl_offset[1]
305 // << "," << asl_offset[2] << endl;
306 sgAddVec3( asl_offset, p );
307 // cout << " asl_offset = " << asl_offset[0] << "," << asl_offset[1]
308 // << "," << asl_offset[2] << endl;
310 // Translate to zero elevation
311 // Point3D zero_elev = current_view.get_cur_zero_elev();
312 // xglTranslatef( zero_elev.x(), zero_elev.y(), zero_elev.z() );
313 sgMakeTransMat4( T1, asl_offset );
315 // printf(" Translated to %.2f %.2f %.2f\n",
316 // zero_elev.x, zero_elev.y, zero_elev.z );
318 // Rotate to proper orientation
319 // printf(" lon = %.2f lat = %.2f\n",
320 // lon * SGD_RADIANS_TO_DEGREES,
321 // lat * SGD_RADIANS_TO_DEGREES);
322 // xglRotatef( lon * SGD_RADIANS_TO_DEGREES, 0.0, 0.0, 1.0 );
323 sgSetVec3( axis, 0.0, 0.0, 1.0 );
324 sgMakeRotMat4( LON, lon * SGD_RADIANS_TO_DEGREES, axis );
326 // xglRotatef( 90.0 - f->get_Latitude() * SGD_RADIANS_TO_DEGREES,
328 sgSetVec3( axis, 0.0, 1.0, 0.0 );
329 sgMakeRotMat4( LAT, 90.0 - lat * SGD_RADIANS_TO_DEGREES, axis );
333 sgCopyMat4( TRANSFORM, T1 );
334 sgPreMultMat4( TRANSFORM, LON );
335 sgPreMultMat4( TRANSFORM, LAT );
338 sgSetCoord( &layerpos, TRANSFORM );
340 layer_transform->setTransform( &layerpos );
342 // now calculate update texture coordinates
343 if ( last_lon < -900 ) {
348 double sp_dist = speed*dt;
350 if ( lon != last_lon || lat != last_lat || sp_dist != 0 ) {
351 Point3D start( last_lon, last_lat, 0.0 );
352 Point3D dest( lon, lat, 0.0 );
353 double course = 0.0, dist = 0.0;
356 calc_gc_course_dist( dest, start, &course, &dist );
358 // cout << "course = " << course << ", dist = " << dist << endl;
361 // calculate cloud movement due to external forces
362 double ax = 0.0, ay = 0.0, bx = 0.0, by = 0.0;
365 ax = cos(course) * dist;
366 ay = sin(course) * dist;
370 bx = cos(-direction * SGD_DEGREES_TO_RADIANS) * sp_dist;
371 by = sin(-direction * SGD_DEGREES_TO_RADIANS) * sp_dist;
375 double xoff = (ax + bx) / (2 * scale);
376 double yoff = (ay + by) / (2 * scale);
378 const float layer_scale = layer_span / scale;
380 // cout << "xoff = " << xoff << ", yoff = " << yoff << endl;
384 base = tl[0]->get( 0 );
387 // the while loops can lead to *long* pauses if base[0] comes
388 // with a bogus value.
389 // while ( base[0] > 1.0 ) { base[0] -= 1.0; }
390 // while ( base[0] < 0.0 ) { base[0] += 1.0; }
391 if ( base[0] > -10.0 && base[0] < 10.0 ) {
392 base[0] -= (int)base[0];
395 SG_LOG(SG_ASTRO, SG_DEBUG,
396 "Error: base = " << base[0] << "," << base[1]);
400 // the while loops can lead to *long* pauses if base[0] comes
401 // with a bogus value.
402 // while ( base[1] > 1.0 ) { base[1] -= 1.0; }
403 // while ( base[1] < 0.0 ) { base[1] += 1.0; }
404 if ( base[1] > -10.0 && base[1] < 10.0 ) {
405 base[1] -= (int)base[1];
408 SG_LOG(SG_ASTRO, SG_ALERT,
409 "Error: base = " << base[0] << "," << base[1]);
412 // cout << "base = " << base[0] << "," << base[1] << endl;
414 for (int i = 0; i < 4; i++)
416 tc = tl[i]->get( 0 );
417 sgSetVec2( tc, base[0] + layer_scale * i/4, base[1] );
419 for (int j = 0; j < 4; j++)
421 tc = tl[i]->get( j*2+1 );
422 sgSetVec2( tc, base[0] + layer_scale * (i+1)/4,
423 base[1] + layer_scale * j/4 );
425 tc = tl[i]->get( (j+1)*2 );
426 sgSetVec2( tc, base[0] + layer_scale * i/4,
427 base[1] + layer_scale * (j+1)/4 );
430 tc = tl[i]->get( 9 );
431 sgSetVec2( tc, base[0] + layer_scale * (i+1)/4,
432 base[1] + layer_scale );
443 void SGCloudLayer::draw() {
444 if ( layer_coverage != SG_CLOUD_CLEAR ) {
445 ssgCullAndDraw( layer_root );
450 // make an ssgSimpleState for a cloud layer given the named texture
451 ssgSimpleState *sgCloudMakeState( const string &path ) {
452 ssgSimpleState *state = new ssgSimpleState();
454 cout << " texture = " << path << endl;
456 state->setTexture( (char *)path.c_str() );
457 state->setShadeModel( GL_SMOOTH );
458 state->disable( GL_LIGHTING );
459 state->disable( GL_CULL_FACE );
460 state->enable( GL_TEXTURE_2D );
461 state->enable( GL_COLOR_MATERIAL );
462 state->setColourMaterial( GL_AMBIENT_AND_DIFFUSE );
463 state->setMaterial( GL_EMISSION, 0, 0, 0, 1 );
464 state->setMaterial( GL_SPECULAR, 0, 0, 0, 1 );
465 state->enable( GL_BLEND );
466 state->enable( GL_ALPHA_TEST );
467 state->setAlphaClamp( 0.01 );
469 // ref() the state so it doesn't get deleted if the last layer of
470 // it's type is deleted.