Actionscript 2: Get Y-coordinates from lineTo

Question

So I am drawing a graph with lineTo.

What I want to do is loop through every x coordinate on the lineTo get its Y coordinate and push that to an array, but how do I know what the Y coordinate is at each X coordinate?

Do you want to know the y values between two x points? Is it something like drawing a graph in your exercise book and reading the value at a certain x? In other words, are you asking how to interpolate the values between the given points, which were used to draw the graph? — anemgyenge
I dont want to say Yes incase I misunderstood you, ill try and explain it simply. I have a lineTo function, I want to take the starting X point of the lineTo and the finishing X point of the lineTo and loop through every X value inbetween and get its corresponding Y value (where the line on the Y value at X) and then push that Y value to an array. — George Reith

DigitalD DigitalD · Accepted Answer · 2011-07-15T14:19:05

var lineStartX=10;
var lineStartY=10;
var lineEndX=450;
var lineEndY=300;
this.lineStyle(5, 0xFF00FF, 100);
this.moveTo(lineStartX, lineStartY);
this.lineTo(lineEndX, lineEndY);

var ratio=(lineEndY-lineStartY)/(lineEndX-lineStartX);
for (var yV:Number=0; yV<=lineEndY-lineStartY; yV+=5) {
 var xV=yV/ratio+lineStartX;

 //Vizualize// 
 this.lineStyle(2, 0xFFF0F0, 100);
 this.moveTo(xV, yV+lineStartY);
 this.lineTo(xV+1, yV+lineStartY+1);
}

for (var xV:Number=0; xV<=lineEndX-lineStartX; xV+=5) {
 var yV=xV*ratio+lineStartY;
}

Actionscript 2: Get Y-coordinates from lineTo

2 Answers