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flightgear/src/AIModel/AIBallistic.hxx

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Add David Culp's AI model manager code which is derived from David Luff's AI/ATC code.
2003-11-28 15:48:05 +00:00
// FGAIBallistic - AIBase derived class creates an AI ballistic object
//
// Written by David Culp, started November 2003.
// - davidculp2@comcast.net
//
// This program is free software; you can redistribute it and/or
// modify it under the terms of the GNU General Public License as
// published by the Free Software Foundation; either version 2 of the
// License, or (at your option) any later version.
//
// This program is distributed in the hope that it will be useful, but
// WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
// General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
#ifndef _FG_AIBALLISTIC_HXX
#define _FG_AIBALLISTIC_HXX
#include "AIManager.hxx"
#include "AIBase.hxx"
class FGAIBallistic : public FGAIBase {
public:
David Culp: Here's a new batch of AI code which includes a working radar instrument. I put the radar calculations into the existing AIAircraft class. It was easier that way, and it can always be migrated out later if we have to. Every tenth sim cycle the AIManager makes a copy of the current user state information. When the AIAircraft updates it uses this information to calculate the radar numbers. It calculates: 1) bearing from user to target 2) range to target in nautical miles 3) "horizontal offset" to target. This is the angle from the nose to the target, in degrees, from -180 to 180. This will be useful later for a HUD. 4) elevation, in degrees (vertical angle from user's position to target position) 5) vertical offset, in degrees (this is elevation corrected for user's pitch) 6) rdot (range rate in knots, note: not working yet, so I commented it out) and three items used by the radar instrument to place the "blip" 7) y_shift, in nautical miles 8) x_shift, in nautical miles 9) rotation, in degrees The radar instrument uses the above three items, and applies a scale factor to the x-shift and y-shift in order to match the instrument's scale. Changing the display scale can be done entirely in the XML code for the instrument. Right now it's set up only to display a 40 mile scale. The radar is an AWACS view, which is not very realistic, but it is useful and demonstrates the technology. With just a little more work I can get a HUD marker. All I need to do there is make a bank angle adjustment to the current values.
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FGAIBallistic(FGAIManager* mgr);
Add David Culp's AI model manager code which is derived from David Luff's AI/ATC code.
2003-11-28 15:48:05 +00:00
~FGAIBallistic();
bool init();
Make the AI model export it's internal state to the property tree under /ai/model[] using the same naming convention as used for the regular FDM. Also make sure the model animations are relative the the /ai/model[] node.
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virtual void bind();
virtual void unbind();
Add David Culp's AI model manager code which is derived from David Luff's AI/ATC code.
2003-11-28 15:48:05 +00:00
void update(double dt);
void setAzimuth( double az );
void setElevation( double el );
void setStabilization( bool val );
David Culp: Silly me. I was starting the timer at zero, so the first tracer didn't fly until 0.25 seconds after pulling the trigger. Now the timer starts at the same value as "delay", so the first round comes out immediately. Also, I've added an optional configuration attribute that allows you to change the ballistics of the submodel. This allows parachutes, or anything else that has ballistics different from a bullet. The attribute is called "eda", which is the equivalent drag area. Default value is 0.007, which gives the same ballistics as the current tracers. Increasing this value gives more drag. A value of 2.0 looks good for a parachute. math stuff ######################################################################## The deceleration of the ballictic object is now given by: [ (rho) (Cd) ] / [ (1/2) (m) ] * A * (V * V) where rho is sea-level air density, and Cd and m are fixed, bullet-like values. So the calculation is: 0.0116918 * A * (V * V) The value "A" is what I'm calling the "eda" (equivalent drag area). ######################################################################## A parachute model will have to be built so that the parachutist's feet are in the forward x-direction. Here is the submodel.xml config I use for "parachutes": <submodel> <name>flares</name> <model>Models/Geometry/flare.ac</model> <trigger>systems/submodels/submodel[0]/trigger</trigger> <speed>0.0</speed> <repeat>true</repeat> <delay>0.85</delay> <count>4</count> <x-offset>0.0</x-offset> <y-offset>0.0</y-offset> <z-offset>-4.0</z-offset> <yaw-offset>0.0</yaw-offset> <pitch-offset>0.0</pitch-offset> <eda>2.0</eda> </submodel>
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void setDragArea( double a );
David Culp: Here are small changes that allow one to set a life-span for submodels.
2004-08-30 09:11:59 +00:00
void setLife( double seconds );
Vivian Meazza: I've added another parameter to the submodel - wind. It's activated by the entry <wind>true</wind> in the ../submodel.xml file. If true, the submodel is affected by the local wind, otherwise not. The parameter defaults to false. This is useful for exhausts and smoke, and possibly all objects.
2004-09-05 09:45:34 +00:00
void setBuoyancy( double fpss );
void setWind_from_east( double fps );
void setWind_from_north( double fps );
void setWind( bool val );
Vivian Meazza: Attached are the modified files to add buoyancy as a parameter for a ballistic object. It may be set by adding <buoyancy>x</buoyancy> to the submodel .xml file, where x is the appropriate value (ft per sec2): 32 neutral buoyancy - contrails >32 positive buoyancy - exhaust plumes (0 non-op - default value) If <buoyancy>x</buoyancy> is not used, then there is no effect on the current ballistic model
2004-09-01 08:32:54 +00:00
Add David Culp's AI model manager code which is derived from David Luff's AI/ATC code.
2003-11-28 15:48:05 +00:00
private:
double azimuth; // degrees true
double elevation; // degrees
double hs; // horizontal speed (fps)
bool aero_stabilized; // if true, object will point where it's going
David Culp: Silly me. I was starting the timer at zero, so the first tracer didn't fly until 0.25 seconds after pulling the trigger. Now the timer starts at the same value as "delay", so the first round comes out immediately. Also, I've added an optional configuration attribute that allows you to change the ballistics of the submodel. This allows parachutes, or anything else that has ballistics different from a bullet. The attribute is called "eda", which is the equivalent drag area. Default value is 0.007, which gives the same ballistics as the current tracers. Increasing this value gives more drag. A value of 2.0 looks good for a parachute. math stuff ######################################################################## The deceleration of the ballictic object is now given by: [ (rho) (Cd) ] / [ (1/2) (m) ] * A * (V * V) where rho is sea-level air density, and Cd and m are fixed, bullet-like values. So the calculation is: 0.0116918 * A * (V * V) The value "A" is what I'm calling the "eda" (equivalent drag area). ######################################################################## A parachute model will have to be built so that the parachutist's feet are in the forward x-direction. Here is the submodel.xml config I use for "parachutes": <submodel> <name>flares</name> <model>Models/Geometry/flare.ac</model> <trigger>systems/submodels/submodel[0]/trigger</trigger> <speed>0.0</speed> <repeat>true</repeat> <delay>0.85</delay> <count>4</count> <x-offset>0.0</x-offset> <y-offset>0.0</y-offset> <z-offset>-4.0</z-offset> <yaw-offset>0.0</yaw-offset> <pitch-offset>0.0</pitch-offset> <eda>2.0</eda> </submodel>
2004-08-26 16:25:54 +00:00
double drag_area; // equivalent drag area in ft2
David Culp: Here are small changes that allow one to set a life-span for submodels.
2004-08-30 09:11:59 +00:00
double life_timer; // seconds
Vivian Meazza: I've added another parameter to the submodel - wind. It's activated by the entry <wind>true</wind> in the ../submodel.xml file. If true, the submodel is affected by the local wind, otherwise not. The parameter defaults to false. This is useful for exhausts and smoke, and possibly all objects.
2004-09-05 09:45:34 +00:00
double gravity; // fps2
double buoyancy; // fps2
double wind_from_east; // fps
double wind_from_north; // fps
bool wind; // if true, local wind will be applied to object
Vivian Meazza: Attached are the modified files to add buoyancy as a parameter for a ballistic object. It may be set by adding <buoyancy>x</buoyancy> to the submodel .xml file, where x is the appropriate value (ft per sec2): 32 neutral buoyancy - contrails >32 positive buoyancy - exhaust plumes (0 non-op - default value) If <buoyancy>x</buoyancy> is not used, then there is no effect on the current ballistic model
2004-09-01 08:32:54 +00:00
Add David Culp's AI model manager code which is derived from David Luff's AI/ATC code.
2003-11-28 15:48:05 +00:00
void Run(double dt);
};
#endif // _FG_AIBALLISTIC_HXX
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