node functions

lock rt to time:seconds + nextnode:eta + nextnode:orbit:period.
lock dist to (positionat(ship, rt) - positionat(target, rt)):mag.
function closest {
	parameter sgt is time:seconds.
	parameter sgstep to 1.
	set sgmindist to 9e9.
	lock sgdist to (positionat(ship, sgt) - positionat(target, sgt)):mag.
	until sgt - time:seconds > orbit:period {
		if sgdist < sgmindist {
			set sgmindist to sgdist.
			set sgmint to sgt.
		}
		set sgt to sgt + sgstep.
	}
	print sgmint. print sgmindist.
	return sgmint.
}

function increment  {
	parameter step.
	parameter type is "e".

	if type = "e" set nextnode:eta to nextnode:eta + step.
	if type = "p" set nextnode:prograde to nextnode:prograde + step.
	if type = "n" set nextnode:normal to nextnode:normal + step.
	if type = "ro" set nextnode:radialout to nextnode:radialout + step.
}

function adjust {
	parameter type is "e".
	set lastdist to dist.
	until lastdist < dist {
		set lastdist to dist.  increment(step, type). wait 0. print dist.
	}.
}

function tweak {
	parameter type is "e".
	adjust(type).
	set step to -step/2.
	adjust(type).
	increment(-step, type).
	print dist.
}

set step to 1.

Lock sf to 1.
Function nodeset {
	parameter n.
	parameter q.

	set n:radialout to q:x.
	set n:normal to q:y.
	set n:prograde to q:z. wait 0.
}
function nodeget {
	parameter n.
	return v(n:radialout,n:normal, n:prograde).
}

function nodedelta {
	parameter n.
	parameter d.
	nodeset(n,nodeget(n)+d).
}

function grad {
	parameter n.
	parameter d is 0.001.
	local y0 is sf.
	local v0 is nodeget(n).

	 function t {
		parameter q.
		nodedelta(n,d*q).
		local y is (sf-y0)/d.
		return y.
	}

	local x is t(v(1,0,0)).
	local y is t(v(-1,1,0)).
	local z is t(v(0,-1,1)).
	nodeset(n,v0).
	return v(x,y,z).
}.
function matchVelAtNode2 {
	parameter nodeX is nextnode.
	parameter tarvel is "none".

	set tx to nodeX:time.

	set nodeX:prograde to 0.
	set nodeX:radialout to 0.
	set nodeX:normal to 0.

	wait 0.1.

	set nodepro to velocityat(ship, tx):orbit:normalized.
	set noderad to vxcl(nodepro, (positionat(ship, tx) - body:position)):normalized.
	set nodenorm to vcrs(nodepro, noderad):normalized.

	set tarvel to choose tarvel - velocityat(ship, tx):orbit if tarvel:istype("vector") else velocityat(target, tx):orbit - velocityat(ship, tx):orbit.

	set pro to vdot(nodepro, tarvel).
	set rad to vdot(noderad, tarvel).
	set norm to vdot(nodenorm, tarvel).

	set nodeX:prograde to pro.
	set nodeX:radialout to rad.
	set nodeX:normal to norm.
}