//	File	: DogFight.c
//	Author	: John Wojcik ( QuietBloke )
//	Created	: September 2000
//	Desc	: My first game written using my 2D Game framework.
//		The game is very simple. Two biplanes battle it out in the
//		Yaroze sky for air supremacy.
//
//	History	:
// Date     Author          Description
// -------- --------------- ----------------------------------------

#include <stdio.h>

#include <libps.h>
#include "fw.h"
#include "pad.h"
#include "Dogfight.h"
#include "PlaneMov.h"

void MovePlane ( int CurrentPlayer )
{
	int	TargetSpeedModifier;
	int	PlaneAngle;

	PlaneAngle = fwActorGetAngle( PlaneActor[CurrentPlayer] );
	// Sin/Cos functions return a value between 0 and 255
	TargetSpeedModifier = ( fwAngleGetCos ( PlaneAngle ) * fwAngleGetCos ( PlaneAngle ) ) >> 8;

	// Modifier becomes a value between 0 and .25 * PlaneAcceleration
	TargetSpeedModifier = (TargetSpeedModifier * PlaneAcceleration ) >> 10;
}

void AcceleratePlane ( int CurrentPlayer )
{
	int	TempSpeed;
	int	TargetSpeedModifier;
	int	AllowedSpeed;
	int	PlaneAngle;

	// Before we do anything decelerate the plane ( Plane drag )

	TempSpeed = fwAnimateGetChangeValue( XPlaneAnim[CurrentPlayer] );
	TempSpeed = TempSpeed * PlaneDeceleration / 100;
	fwAnimateSetChangeValue ( XPlaneAnim[CurrentPlayer], TempSpeed );

	TempSpeed = fwAnimateGetChangeValue( YPlaneAnim[CurrentPlayer] );
	TempSpeed = TempSpeed * PlaneDeceleration / 100;
	fwAnimateSetChangeValue ( YPlaneAnim[CurrentPlayer], TempSpeed );			

	PlaneAngle = fwActorGetAngle( PlaneActor[CurrentPlayer] );
	// Sin/Cos functions return a value between 0 and 255
	TargetSpeedModifier = ( fwAngleGetCos ( PlaneAngle ) * fwAngleGetCos ( PlaneAngle ) ) >> 8;

	// Modifier becomes a value between 0 and .5 * PlaneAcceleration
	TargetSpeedModifier = (TargetSpeedModifier * PlaneAcceleration ) >> 9;

	if ( PlaneAngle < 90 || PlaneAngle > 270 )
		TargetSpeedModifier *= -1;

	// Because we are dealing with int's the PlaneAccel is stored as a fixed point field
	// Convert calculations appropriately.
	AllowedSpeed = ( PlaneAcceleration + TargetSpeedModifier ) << PLANE_ACCEL_SHIFT;

	if ( PlaneAccel[CurrentPlayer] < AllowedSpeed )
		PlaneAccel[CurrentPlayer]++;
	if ( PlaneAccel[CurrentPlayer] > AllowedSpeed )
		PlaneAccel[CurrentPlayer]--;

	// Now apply the plane acceleration 
	fwActorAddVelocity ( PlaneActor[CurrentPlayer], fwActorGetAngle ( PlaneActor[CurrentPlayer] ), ( PlaneAccel[CurrentPlayer] >> PLANE_ACCEL_SHIFT ) );

	// NOTE : deceleration is performed as a percentage of the previous 
	// speed. Acceleration is a simple addition. Therefore drag increases
	// as speed increases and we naturally get a max speed for the plane.

	// Now add the gravity factor
	fwActorAddVelocity ( PlaneActor[CurrentPlayer] ,180, Gravity );
}

void FreeFallPlane ( int CurrentPlayer )
{
	int	TempSpeed;

	// Before we do anything decelerate the plane ( Plane drag )

	// NOTE : When falling only apply the drag to the x movement
	TempSpeed = fwAnimateGetChangeValue( XPlaneAnim[CurrentPlayer] );
	TempSpeed = TempSpeed * PlaneDeceleration / 100;
	fwAnimateSetChangeValue ( XPlaneAnim[CurrentPlayer], TempSpeed );

	// Now add the gravity factor
	fwActorAddVelocity ( PlaneActor[CurrentPlayer] ,180, (Gravity<<2) );	

	TempSpeed = fwAnimateGetChangeValue( YPlaneAnim[CurrentPlayer] );
	// We cant fall faster than the plane can fly.. it would be daft
	if ( TempSpeed > (PlaneAcceleration<<1) )
	{
		TempSpeed = (PlaneAcceleration<<1);
	}
	fwAnimateSetChangeValue ( YPlaneAnim[CurrentPlayer], TempSpeed );

}