double TauMCMissile::get_aim(SpaceObject *tgt)
{
STACKTRACE;
Vector2 tv = tgt->get_vel();
//double tvy = tgt->get_vy();
//double rx = min_delta(tgt->normal_x(), normal_x(), X_MAX);
//double ry = min_delta(tgt->normal_y(), normal_y(), Y_MAX);
Vector2 r = min_delta(tgt->normal_pos(), normal_pos());
//rx*rx + ry*ry;
double r2 = magnitude_sqr(r);
double u2 = v * v;
//(tvx*tvx + tvy*tvy);
double d2v = u2 - magnitude_sqr(tv);
double t = r.dot(tv); //(rx*tvx + ry*tvy);
double q, p;
if (fabs(d2v/u2) > 0.01 ) {
q = t*t + r2*d2v;
if (q > 0) q = sqrt(q);
else return (1e10);
p = (t+q)/d2v;
q = (t-q)/d2v;
if (p > 0) t = p;
else t = q;
if (t < 0) return (1e10);
} else {
if (fabs(t)<1e-6) return (1e10);
else t = - 0.5 * r2 / t;
if (t < 0) return (1e10);
}
t = normalize(atan3(tv.y*t + r.y, tv.x*t + r.x) - angle, PI2);
if (t > PI) t -= PI2;
return (t);
}
// This method assumes the limits have already been checked.
// This method assumes the start and end radius match.
// This method assumes arcs are not >180 degrees (PI radians)
// cx/cy - center of circle
// x/y - end position
// dir - ARC_CW or ARC_CCW to control direction of arc
static void arc(float cx,float cy,float x,float y,float dir) {
// get radius
float dx = px - cx;
float dy = py - cy;
float radius=sqrt(dx*dx+dy*dy);
// find angle of arc (sweep)
float angle1=atan3(dy,dx);
float angle2=atan3(y-cy,x-cx);
float theta=angle2-angle1;
if(dir>0 && theta<0) angle2+=2*PI;
else if(dir<0 && theta>0) angle1+=2*PI;
theta=angle2-angle1;
// get length of arc
// float circ=PI*2.0*radius;
// float len=theta*circ/(PI*2.0);
// simplifies to
float len = abs(theta) * radius;
int i, segments = ceil( len * MM_PER_SEGMENT );
float nx, ny, angle3, scale;
for(i=0;i<segments;++i) {
// interpolate around the arc
scale = ((float)i)/((float)segments);
angle3 = ( theta * scale ) + angle1;
nx = cx + cos(angle3) * radius;
ny = cy + sin(angle3) * radius;
// send it to the planner
line(nx,ny);
}
line(x,y);
}
Type bearing(Type x0, Type y0, Type x1, Type y1, bool nautical = true){
vector<Type> dx(2);
if(nautical){
dx(0) = x1-x0;
dx(1) = y1-y0;
}else{
dx = ll2n(x1,y1) - ll2n(x0,y0);
}
return atan3(dx(1),dx(0));
}
double VelronCruiser::get_aim(SpaceObject *tgt, double min_angle, double max_angle)
{
STACKTRACE;
if (tgt == NULL)
return (-1000);
Vector2 tv = tgt->get_vel() - specialRelativity * vel;
double tvx = tv.x;
double tvy = tv.y;
tv = min_delta(tgt->normal_pos(), pos);
double rx = tv.x;
double ry = tv.y;
double r2 = rx*rx + ry*ry;
double u2 = specialVelocity;
u2 *= u2;
double d2v = u2 - (tvx*tvx + tvy*tvy);
double t = (rx*tvx + ry*tvy);
double q, p;
if (fabs(d2v/u2) > 0.01 ) {
q = t*t + r2*d2v;
if (q > 0) q = sqrt(q);
else return (-1000);
p = (t+q)/d2v;
q = (t-q)/d2v;
if (p > 0) t = p;
else t = q;
if (t < 0) return (-1000);
} else {
if (fabs(t)<1e-6) return (-1000);
else t = - 0.5 * r2 / t;
if (t < 0) return (-1000);
}
if (t * specialVelocity > specialRange) return(-1000);
t = normalize((atan3(tvy*t + ry, tvx*t + rx)) - angle, PI2);
double d_a = normalize(t - min_angle, PI2);
if (d_a > PI) d_a -= PI2;
if (d_a > 0) {
d_a = normalize(t - max_angle, PI2);
if (d_a > PI) d_a -= PI2;
if (d_a < 0)
return (t);
}
return (-1000);
}
