user3332086 - 9 months ago 49

iOS Question

How to get **all X,Y coordinates** between two points.

I want to move a UIButton in a diagonal pattern in objective C.

Example. To move UIButton from position 'Point A' towards position 'Point B'.

`.Point B`

. Point A

Thanks in advance.

Answer Source

you can use Bresenham's line algorithm

Here is a slightly simplified version, I have used a bunch of times

```
+(NSArray*)getAllPointsFromPoint:(CGPoint)fPoint toPoint:(CGPoint)tPoint
{
/*Simplified implementation of Bresenham's line algoritme */
NSMutableArray *ret = [NSMutableArray array];
float deltaX = fabsf(tPoint.x - fPoint.x);
float deltaY = fabsf(tPoint.y - fPoint.y);
float x = fPoint.x;
float y = fPoint.y;
float err = deltaX-deltaY;
float sx = -0.5;
float sy = -0.5;
if(fPoint.x<tPoint.x)
sx = 0.5;
if(fPoint.y<tPoint.y)
sy = 0.5;
do {
[ret addObject:[NSValue valueWithCGPoint:CGPointMake(x, y)]];
float e = 2*err;
if(e > -deltaY)
{
err -=deltaY;
x +=sx;
}
if(e < deltaX)
{
err +=deltaX;
y+=sy;
}
} while (round(x) != round(tPoint.x) && round(y) != round(tPoint.y));
[ret addObject:[NSValue valueWithCGPoint:tPoint]];//add final point
return ret;
}
```

If you simply want to animate a `UIControl`

from one location to another, you might want to use `UIAnimation`

:

```
[UIView animateWithDuration:1.0f delay:0.0f options:UIViewAnimationOptionCurveLinear animations:^{
btn.center = CGPointMake(<NEW_X>, <NEW_Y>)
} completion:^(BOOL finished) {
}];
```