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David Culp:

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Here are some things I've added to the submodel code.

First, I added a first_time value that is true when the trigger is pressed and
false when the trigger is released.  The true value is also made false after
the first pass through release().  Release() then uses this to force the
first dt (per salvo) to be zero.  I was hoping this would make the submodel
appear closer to the airplane, but I don't notice a difference with the
tracers.  In a prior test I found that the first dt is about 2.5 times larger
than subsequent ones.  Maybe this will be effective with slower submodels,
like smoke, contrails, etc.

Secondly, I updated the IC.elevation and IC.azimuth calcs to correctly add in
the yaw and pitch offsets, corrected for bank angle.  Actually this is still
an estimation.  A proper calculation will sum the submodels vector with the
airplane's vector.  Until that's done only models which are fired forward
will have proper IC.
This commit is contained in:
ehofman 2004-09-09 08:40:08 +00:00
parent bfd8a50294
commit d712d18acb
2 changed files with 50 additions and 48 deletions
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57
src/Systems/submodel.cxx
View file

@ -43,6 +43,7 @@ SubmodelSystem::init ()
_user_pitch_node = fgGetNode("/orientation/pitch-deg", true);
_user_roll_node = fgGetNode("/orientation/roll-deg", true);
_user_yaw_node = fgGetNode("/orientation/yaw-deg", true);
_user_alpha_node = fgGetNode("/orientation/alpha-deg", true);
_user_speed_node = fgGetNode("/velocities/uBody-fps", true);
@ -81,6 +82,8 @@ SubmodelSystem::update (double dt)
if ((*submodel_iterator)->count != 0) {
release( (*submodel_iterator), dt);
}
} else {
(*submodel_iterator)->first_time = true;
}
++submodel_iterator;
}
@ -94,9 +97,13 @@ SubmodelSystem::release (submodel* sm, double dt)
if (sm->timer < sm->delay) return false;
sm->timer = 0.0;
if (sm->first_time) {
dt = 0.0;
sm->first_time = false;
}
transform(sm); // calculate submodel's initial conditions in world-coordinates
//cout << "Creating a submodel." << endl;
FGAIModelEntity entity;
entity.path = sm->model.c_str();
@ -114,7 +121,6 @@ SubmodelSystem::release (submodel* sm, double dt)
entity.wind = sm->wind;
ai->createBallistic( &entity );
//cout << "Submodel created." << endl;
if (sm->count > 0) (sm->count)--;
return true;
@ -164,6 +170,7 @@ SubmodelSystem::load ()
sm->life = entry_node->getDoubleValue("life", 900.0);
sm->buoyancy = entry_node->getDoubleValue("buoyancy", 0);
sm->wind = entry_node->getBoolValue ("wind", false);
sm->first_time = false;
sm->trigger->setBoolValue(false);
sm->timer = sm->delay;
@ -171,16 +178,11 @@ SubmodelSystem::load ()
sm->prop = fgGetNode("/systems/submodels/submodel", i, true);
sm->prop->tie("count", SGRawValuePointer<int>(&(sm->count)));
// in[0] = sm->x_offset;
// in[1] = sm->y_offset;
// in[2] = sm->z_offset;
submodels.push_back( sm );
}
submodel_iterator = submodels.begin();
// cout << submodels.size() << " submodels read." << endl;
}
@ -197,7 +199,7 @@ SubmodelSystem::transform( submodel* sm)
IC.elevation = _user_pitch_node->getDoubleValue(); // rotation about y axis
IC.azimuth = _user_heading_node->getDoubleValue(); // rotation about z axis
IC.speed = _user_speed_node->getDoubleValue() + sm->speed;
IC.speed = _user_speed_node->getDoubleValue();
IC.wind_from_east = _user_wind_from_east_node->getDoubleValue();
IC.wind_from_north = _user_wind_from_north_node->getDoubleValue();
@ -205,8 +207,6 @@ SubmodelSystem::transform( submodel* sm)
in[1] = sm->y_offset;
in[2] = sm->z_offset;
// pre-process the trig functions
cosRx = cos(IC.roll * SG_DEGREES_TO_RADIANS);
@ -216,7 +216,6 @@ SubmodelSystem::transform( submodel* sm)
cosRz = cos(IC.azimuth * SG_DEGREES_TO_RADIANS);
sinRz = sin(IC.azimuth * SG_DEGREES_TO_RADIANS);
// set up the transform matrix
trans[0][0] = cosRy * cosRz;
@ -234,31 +233,33 @@ SubmodelSystem::transform( submodel* sm)
// multiply the input and transform matrices
// for( int i=0; i<4; i++) {
// for( int j=0; j<4; j++ ) {
// out[i] += in[j] * trans[i][j];
// }
// }
out[0] = in[0] * trans[0][0] + in[1] * trans[0][1] + in[2] * trans[0][2];
out[1] = in[0] * trans[1][0] + in[1] * trans[1][1] + in[2] * trans[1][2];
out[2] = in[0] * trans[2][0] + in[1] * trans[2][1] + in[2] * trans[2][2];
// convert ft to degrees of latitude
out[0] = in[0] * trans[0][0] + in[1] * trans[0][1] + in[2] * trans[0][2];
out[1] = in[0] * trans[1][0] + in[1] * trans[1][1] + in[2] * trans[1][2];
out[2] = in[0] * trans[2][0] + in[1] * trans[2][1] + in[2] * trans[2][2];
// convert ft to degrees of latitude
out[0] = out[0] /(366468.96 - 3717.12 * cos(IC.lat * SG_DEGREES_TO_RADIANS));
// convert ft to degrees of longitude
// convert ft to degrees of longitude
out[1] = out[1] /(365228.16 * cos(IC.lat * SG_DEGREES_TO_RADIANS));
// set submodel initial position
IC.lat += out[0];
IC.lon += out[1];
IC.alt += out[2];
IC.elevation += sm->pitch_offset;
IC.azimuth += sm->yaw_offset;
// get aircraft velocity vector angles in XZ and XY planes
//double alpha = _user_alpha_node->getDoubleValue();
//double velXZ = IC.elevation - alpha * cosRx;
//double velXY = IC.azimuth - (IC.elevation - alpha * sinRx);
// Get submodel initial velocity vector angles in XZ and XY planes.
// This needs to be fixed. This vector should be added to aircraft's vector.
IC.elevation += (sm->pitch_offset * cosRx) + (sm->yaw_offset * sinRx);
IC.azimuth += (sm->yaw_offset * cosRx) - (sm->pitch_offset * sinRx);
// For now assume vector is close to airplane's vector. This needs to be fixed.
IC.speed += sm->speed;
}

5
src/Systems/submodel.hxx
View file

@ -46,7 +46,7 @@ public:
double life;
double buoyancy;
bool wind;
bool first_time;
} submodel;
typedef struct {
@ -59,7 +59,6 @@ public:
double speed;
double wind_from_east;
double wind_from_north;
} IC_struct;
SubmodelSystem ();
@ -108,11 +107,13 @@ private:
SGPropertyNode* _user_pitch_node;
SGPropertyNode* _user_roll_node;
SGPropertyNode* _user_yaw_node;
SGPropertyNode* _user_alpha_node;
SGPropertyNode* _user_speed_node;
SGPropertyNode* _user_wind_from_east_node;
SGPropertyNode* _user_wind_from_north_node;
FGAIManager* ai;
IC_struct IC;
};
#endif // __SYSTEMS_SUBMODEL_HXX