Custom movement issue

[Boba Fonts]

I'll try to explain my problem.
I must move a character from a X,Y to another X,Y pair of coordinates. I know there are extensions, such as MoveIt, that can move it directly from start point to destination point, but as far as I know they use a constant speed. But I'm already using a custom walking movement that sets, for the main 8 directions, an anti-glide effect, and I definitely want to use it because it's very natural.
Look at the image below:



the same is set for each main direction, so the character walks of a certain amount of pixels not always but only every 00"08, and that amount of pixels depends on the scale, for perspective purposes.
That's why a fixed speed doesn't fit my needs.
How can I move a character using those events from point A to point B?



For example, if the destination point is almost on the vertical of the start point (let's say -220 on the Y, and +24 on the I can make the character move with its custom movement until its Y coordinate reaches the destination's Y, nothing's easier: it goes up 220 pixels; now, how can I know how much time will it take to get there in order to calculate how many pixels it must move every 00"08 to cover the 24 pixels on the X?
I suppose I must use sine and cosine, but I need help on that.
thanks

[Mokhtar]

Why not just get the length of the movement segment using the Pythagorean theorem and divide it by the speed?