semi-circle oddity?

[gpholman]

Create a semi-circle (the method doesn't matter but I happened to use a straight line to slice a circle).

Using one of the semi-circles:

Set line width to 'none' and make the fill a light grey.

Clone it, make the clone black then enlarge clone to be 110%.

Put clone at back then select both objects and align top edges.

Why do you get a very thin line showing through the light grey semi-circle from the object beneath?

I've attached a .xar and .jpeg to illustrate.

[mwenz]

Grant,

I don't think the line used to slice was perfectly horizontal in your case. I thought I could see a slight angle at different zoom levels. So I published to PDF and it was more noticeable. At 160% zoom, part of the anti-aliasing disappears on the left side but shows on the right side.

I have attached a new file after trimming a skosh off.

Mike

[Egg Bramhill]

... after trimming a skosh off

WTF is a skosh off Mike?

I agree re the slice, selecting the top nodes on each side of the semi-circle give different Y co-oridinates.

[handrawn]

'skosh' is a 'smidgen' - I believe it is japanese

[Egg Bramhill]

Further to Mikes observations you need to work in integer pixel units. In your attached xar file your inner semi-circle is 595.7 x 197.9 px whilst the 110 % outer is 435.3 x 217.7. This is what's creating the grey top line.

[gwpriester]

A skosh = 1/2 tad

[handrawn]

anti-aliasing differential is causing the line

not working in whole pixels makes this occur/worse depending whether it's a straight line or not

[Egg Bramhill]

Snap.

[handrawn]

[Egg Bramhill]

A skosh = 1/2 tad

Ah, now I understand!

A skosh is half a smidgen.