Edit Menu – x and y positions
Posted: Mon Sep 08, 2014 10:26 pm
I've always had a bit of trouble using the x and y coordinates in the Edit menu – so I've been experimenting! Here are the results:
Assume we have a vertical line, so x1 and x2 are the same. My drawing was at 1:20 scale in mm – not that that matters.
Move:
Entering -500 in the x1 and x2 boxes moves the line 500 to the left of its current position.
Entering +500 in the x1 and x2 boxes moves the line 500 to the right of its current position.
Absolute:
Entering =-500 in the x1 and x2 boxes moves the line to position -500
Entering =+500 in the x1 and x2 boxes moves the line to position +500
All very logical once you think about it! The only slight anomaly is that if you enter a plain 500 in the x1 and y1 boxes the line moves 500 to the right of its current position, the same as +500 would – that's not a real anomaly, just the convention of assuming +ve unless -ve is specified.
As long as you start with the equals sign, you can enter more complicated maths in the boxes if you really want to
It all works the same with the y co-ordinates – or for that matter, just moving one end of the line.
With circles, ovals, squares and rectangles, the move (-500 or +500) works just the same and moves the object 500 to the left or right of its current position.
But the absolute position has very different results because RC records the left and right edges of these objects, not the centre – so with a circle for example if you enter =+500 for both x1 and x2 you will end up with a circle squashed to a straight line! And if you do the same with y1 and y2, you end up with a meaningless dot.
George
Assume we have a vertical line, so x1 and x2 are the same. My drawing was at 1:20 scale in mm – not that that matters.
Move:
Entering -500 in the x1 and x2 boxes moves the line 500 to the left of its current position.
Entering +500 in the x1 and x2 boxes moves the line 500 to the right of its current position.
Absolute:
Entering =-500 in the x1 and x2 boxes moves the line to position -500
Entering =+500 in the x1 and x2 boxes moves the line to position +500
All very logical once you think about it! The only slight anomaly is that if you enter a plain 500 in the x1 and y1 boxes the line moves 500 to the right of its current position, the same as +500 would – that's not a real anomaly, just the convention of assuming +ve unless -ve is specified.
As long as you start with the equals sign, you can enter more complicated maths in the boxes if you really want to
It all works the same with the y co-ordinates – or for that matter, just moving one end of the line.
With circles, ovals, squares and rectangles, the move (-500 or +500) works just the same and moves the object 500 to the left or right of its current position.
But the absolute position has very different results because RC records the left and right edges of these objects, not the centre – so with a circle for example if you enter =+500 for both x1 and x2 you will end up with a circle squashed to a straight line! And if you do the same with y1 and y2, you end up with a meaningless dot.
George