Ah ok. I'll work out the exact details tomorrow after I do some testing. Though, I suggest reading up on some trigonometry and maybe even the concept of vectors. Math requires time, hard work and practice, but you don't have to stress about memorizing anything. Just go at your own pace.
If you're looking for some specifics:
For trig:
right angled triangles
Hypotenuse is the non axis aligned side (the slanted side)
sine (sin) = opposite / hypotenuse (S = O/H --> SOH)
cos (cosine) = adjacent / hypotenuse (C = A/H --> CAH)
tangent (tan) = opposite / adjacent (T = O/A --> TOA)
SOH-CAH-TOA
square(A) + square(B) = Square(Hypotenuse)
For Vectors:
addition of vectors graphically
subtraction of vectors graphically
length (magnitude, denoted by |a|)
direction
normalized means that the vector has a length of 1 which is very useful for directions and aiming
multiplying a vector by a scalar (a real number like x = 5, the domain is (-infinity, +infinity))
creating a vector from an angle
getting an angle from the components of a vector
dot product (scalar product) of two vectors which is very useful for things like projecting and determining the magnitude of which two vectors are in the same direction.
dot(a,b) = |a||b|cos@, where a and b are vectors, and @ is the angle between them
dot product = 0 means that the vectors are perpendicular
dot product = 1 when both vectors are normalized means that the vectors are in the exact same direction
dot product = -1 when the vectors are parallel but are in opposite direction
cross product of two vectors gives a perpendicular vector, provided that the two vectors are not parallel
cross product = 0 (zero vector) means that the vectors are parallel
I'm not suggesting that you learn how to do any of these by hand or memorize anything. I'm just suggesting to learn the general concepts so that you can use them for your games. For example, "dot(a,b) = 0" means that the vectors are perpendicular or "aimDirection = normalize(targetPosition - playerPosition)", or "missilePosition += speed * forwardDirection".
Since you're also a spriter, you can use the concept of dot products for determining how much light a surface has. In basic light shaders, graphics programmers use "lightMagnitude = dot(lightDirection, surfaceNormal)". For spriting, it means that the amount of light a surface has is equivalent to figuring out how much the light direction vector and the surface normal direction are facing eachother. When I messed with spriting, thinking of shading like this made things much easier since you're more aware of and visualizing the sprite as a composition of many 3D surfaces.