1 #include "Atmosphere.hpp"
2 #include "Thruster.hpp"
4 #include "RigidBody.hpp"
5 #include "Integrator.hpp"
6 #include "Propeller.hpp"
7 #include "PistonEngine.hpp"
11 #include "Rotorpart.hpp"
12 #include "Rotorblade.hpp"
19 void printState(State* s)
22 Math::vmul33(tmp.orient, tmp.v, tmp.v);
23 Math::vmul33(tmp.orient, tmp.acc, tmp.acc);
24 Math::vmul33(tmp.orient, tmp.rot, tmp.rot);
25 Math::vmul33(tmp.orient, tmp.racc, tmp.racc);
27 printf("\nNEW STATE (LOCAL COORDS)\n");
28 printf("pos: %10.2f %10.2f %10.2f\n", tmp.pos[0], tmp.pos[1], tmp.pos[2]);
32 if(i != 0) printf(" ");
33 printf("%6.2f %6.2f %6.2f\n",
34 tmp.orient[3*i+0], tmp.orient[3*i+1], tmp.orient[3*i+2]);
36 printf("v: %6.2f %6.2f %6.2f\n", tmp.v[0], tmp.v[1], tmp.v[2]);
37 printf("acc: %6.2f %6.2f %6.2f\n", tmp.acc[0], tmp.acc[1], tmp.acc[2]);
38 printf("rot: %6.2f %6.2f %6.2f\n", tmp.rot[0], tmp.rot[1], tmp.rot[2]);
39 printf("rac: %6.2f %6.2f %6.2f\n", tmp.racc[0], tmp.racc[1], tmp.racc[2]);
46 for(i=0; i<3; i++) _wind[i] = 0;
48 _integrator.setBody(&_body);
49 _integrator.setEnvironment(this);
51 // Default value of 30 Hz
52 _integrator.setInterval(1.0f/30.0f);
61 // FIXME: who owns these things? Need a policy
64 void Model::getThrust(float* out)
67 out[0] = out[1] = out[2] = 0;
69 for(i=0; i<_thrusters.size(); i++) {
70 Thruster* t = (Thruster*)_thrusters.get(i);
72 Math::add3(tmp, out, out);
76 void Model::initIteration()
78 // Precompute torque and angular momentum for the thrusters
81 _gyro[i] = _torque[i] = 0;
82 for(i=0; i<_thrusters.size(); i++) {
83 Thruster* t = (Thruster*)_thrusters.get(i);
85 // Get the wind velocity at the thruster location
88 localWind(pos, _s, v);
91 t->setAir(_pressure, _temp, _rho);
92 t->integrate(_integrator.getInterval());
95 Math::add3(v, _torque, _torque);
98 Math::add3(v, _gyro, _gyro);
102 // FIXME: This method looks to me like it's doing *integration*, not
103 // initialization. Integration code should ideally go into
104 // calcForces. Only very "unstiff" problems can be solved well like
105 // this (see the engine code for an example); I don't know if rotor
106 // dynamics qualify or not.
108 void Model::initRotorIteration()
111 float dt = _integrator.getInterval();
113 Math::vmul33(_s->orient, _s->rot, lrot);
114 Math::mul3(dt,lrot,lrot);
115 for(i=0; i<_rotors.size(); i++) {
116 Rotor* r = (Rotor*)_rotors.get(i);
117 r->inititeration(dt);
119 for(i=0; i<_rotorparts.size(); i++) {
120 Rotorpart* rp = (Rotorpart*)_rotorparts.get(i);
121 rp->inititeration(dt,lrot);
123 for(i=0; i<_rotorblades.size(); i++) {
124 Rotorblade* rp = (Rotorblade*)_rotorblades.get(i);
125 rp->inititeration(dt,lrot);
129 void Model::iterate()
132 initRotorIteration();
133 _body.recalc(); // FIXME: amortize this, somehow
134 _integrator.calcNewInterval();
137 bool Model::isCrashed()
142 void Model::setCrashed(bool crashed)
147 float Model::getAGL()
152 State* Model::getState()
157 void Model::setState(State* s)
159 _integrator.setState(s);
160 _s = _integrator.getState();
163 RigidBody* Model::getBody()
168 Integrator* Model::getIntegrator()
173 Surface* Model::getSurface(int handle)
175 return (Surface*)_surfaces.get(handle);
178 Rotorpart* Model::getRotorpart(int handle)
180 return (Rotorpart*)_rotorparts.get(handle);
182 Rotorblade* Model::getRotorblade(int handle)
184 return (Rotorblade*)_rotorblades.get(handle);
186 Rotor* Model::getRotor(int handle)
188 return (Rotor*)_rotors.get(handle);
191 int Model::addThruster(Thruster* t)
193 return _thrusters.add(t);
196 int Model::numThrusters()
198 return _thrusters.size();
201 Thruster* Model::getThruster(int handle)
203 return (Thruster*)_thrusters.get(handle);
206 void Model::setThruster(int handle, Thruster* t)
208 _thrusters.set(handle, t);
211 int Model::addSurface(Surface* surf)
213 return _surfaces.add(surf);
216 int Model::addRotorpart(Rotorpart* rpart)
218 return _rotorparts.add(rpart);
220 int Model::addRotorblade(Rotorblade* rblade)
222 return _rotorblades.add(rblade);
224 int Model::addRotor(Rotor* r)
226 return _rotors.add(r);
229 int Model::addGear(Gear* gear)
231 return _gears.add(gear);
234 void Model::setGroundEffect(float* pos, float span, float mul)
236 Math::set3(pos, _wingCenter);
237 _groundEffectSpan = span;
241 // The first three elements are a unit vector pointing from the global
242 // origin to the plane, the final element is the distance from the
243 // origin (the radius of the earth, in most implementations). So
244 // (v dot _ground)-_ground[3] gives the distance AGL.
245 void Model::setGroundPlane(double* planeNormal, double fromOrigin)
248 for(i=0; i<3; i++) _ground[i] = planeNormal[i];
249 _ground[3] = fromOrigin;
252 void Model::setAir(float pressure, float temp, float density)
254 _pressure = pressure;
259 void Model::setWind(float* wind)
261 Math::set3(wind, _wind);
264 void Model::calcForces(State* s)
266 // Add in the pre-computed stuff. These values aren't part of the
267 // Runge-Kutta integration (they don't depend on position or
268 // velocity), and are therefore constant across the four calls to
269 // calcForces. They get computed before we begin the integration
271 _body.setGyro(_gyro);
272 _body.addTorque(_torque);
274 for(i=0; i<_thrusters.size(); i++) {
275 Thruster* t = (Thruster*)_thrusters.get(i);
276 float thrust[3], pos[3];
277 t->getThrust(thrust);
279 _body.addForce(pos, thrust);
282 // Gravity, convert to a force, then to local coordinates
284 Glue::geodUp(s->pos, grav);
285 Math::mul3(-9.8f * _body.getTotalMass(), grav, grav);
286 Math::vmul33(s->orient, grav, grav);
287 _body.addForce(grav);
289 // Do each surface, remembering that the local velocity at each
290 // point is different due to rotation.
292 faero[0] = faero[1] = faero[2] = 0;
293 for(i=0; i<_surfaces.size(); i++) {
294 Surface* sf = (Surface*)_surfaces.get(i);
296 // Vsurf = wind - velocity + (rot cross (cg - pos))
298 sf->getPosition(pos);
299 localWind(pos, s, vs);
301 float force[3], torque[3];
302 sf->calcForce(vs, _rho, force, torque);
303 Math::add3(faero, force, faero);
305 _body.addForce(pos, force);
306 _body.addTorque(torque);
308 for(i=0; i<_rotorparts.size(); i++) {
309 Rotorpart* sf = (Rotorpart*)_rotorparts.get(i);
311 // Vsurf = wind - velocity + (rot cross (cg - pos))
313 sf->getPosition(pos);
314 localWind(pos, s, vs);
316 float force[3], torque[3];
317 sf->calcForce(vs, _rho, force, torque);
318 //Math::add3(faero, force, faero);
320 sf->getPositionForceAttac(pos);
322 _body.addForce(pos, force);
323 _body.addTorque(torque);
325 for(i=0; i<_rotorblades.size(); i++) {
326 Rotorblade* sf = (Rotorblade*)_rotorblades.get(i);
328 // Vsurf = wind - velocity + (rot cross (cg - pos))
330 sf->getPosition(pos);
331 localWind(pos, s, vs);
333 float force[3], torque[3];
334 sf->calcForce(vs, _rho, force, torque);
335 //Math::add3(faero, force, faero);
337 sf->getPositionForceAttac(pos);
339 _body.addForce(pos, force);
340 _body.addTorque(torque);
343 // Get a ground plane in local coordinates. The first three
344 // elements are the normal vector, the final one is the distance
345 // from the local origin along that vector to the ground plane
346 // (negative for objects "above" the ground)
348 ground[3] = localGround(s, ground);
350 // Account for ground effect by multiplying the vertical force
351 // component by an amount linear with the fraction of the wingspan
353 float dist = ground[3] - Math::dot3(ground, _wingCenter);
354 if(dist > 0 && dist < _groundEffectSpan) {
355 float fz = Math::dot3(faero, ground);
356 fz *= (_groundEffectSpan - dist) / _groundEffectSpan;
358 Math::mul3(fz, ground, faero);
359 _body.addForce(faero);
362 // Convert the velocity and rotation vectors to local coordinates
363 float lrot[3], lv[3];
364 Math::vmul33(s->orient, s->rot, lrot);
365 Math::vmul33(s->orient, s->v, lv);
368 for(i=0; i<_gears.size(); i++) {
369 float force[3], contact[3];
370 Gear* g = (Gear*)_gears.get(i);
371 g->calcForce(&_body, lv, lrot, ground);
372 g->getForce(force, contact);
373 _body.addForce(contact, force);
377 void Model::newState(State* s)
381 // Some simple collision detection
383 float ground[4], pos[3], cmpr[3];
384 ground[3] = localGround(s, ground);
386 for(i=0; i<_gears.size(); i++) {
387 Gear* g = (Gear*)_gears.get(i);
389 // Get the point of ground contact
391 g->getCompression(cmpr);
392 Math::mul3(g->getCompressFraction(), cmpr, cmpr);
393 Math::add3(cmpr, pos, pos);
394 float dist = ground[3] - Math::dot3(pos, ground);
396 // Find the lowest one
401 if(_agl < -1) // Allow for some integration slop
405 // Returns a unit "down" vector for the ground in out, and the
406 // distance from the local origin to the ground as the return value.
407 // So for a given position V, "dist - (V dot out)" will be the height
409 float Model::localGround(State* s, float* out)
411 // Get the ground's "down" vector, this can be in floats, because
412 // we don't need positioning accuracy. The direction has plenty
413 // of accuracy after truncation.
414 out[0] = -(float)_ground[0];
415 out[1] = -(float)_ground[1];
416 out[2] = -(float)_ground[2];
417 Math::vmul33(s->orient, out, out);
419 // The distance from the ground to the Aircraft's origin:
420 double dist = (s->pos[0]*_ground[0]
421 + s->pos[1]*_ground[1]
422 + s->pos[2]*_ground[2] - _ground[3]);
427 // Calculates the airflow direction at the given point and for the
428 // specified aircraft velocity.
429 void Model::localWind(float* pos, State* s, float* out)
431 float tmp[3], lwind[3], lrot[3], lv[3];
433 // Get a global coordinate for our local position, and calculate
435 // FIXME: modify turbulence for altitude, attenuating the vertical
436 // component near the ground.
439 Math::tmul33(s->orient, pos, tmp);
440 for(int i=0; i<3; i++) gpos[i] = s->pos[i] + tmp[i];
441 _turb->getTurbulence(gpos, lwind);
442 Math::add3(_wind, lwind, lwind);
444 Math::set3(_wind, lwind);
447 // Convert to local coordinates
448 Math::vmul33(s->orient, lwind, lwind);
449 Math::vmul33(s->orient, s->rot, lrot);
450 Math::vmul33(s->orient, s->v, lv);
452 _body.pointVelocity(pos, lrot, out); // rotational velocity
453 Math::mul3(-1, out, out); // (negated)
454 Math::add3(lwind, out, out); // + wind
455 Math::sub3(out, lv, out); // - velocity
458 }; // namespace yasim