[Bug] Bezier curves cause pixel inaccuracy (blur)

[ono]

Following screenshot presents two layer of 100x100px images zoomed 400% (pixel mode).



LAYERS:
(1) Square (vector with 4 straight line points, integral pixel size&position) - no bluring
(2) Rounded square/rect (vector with 8 bezier points, integral pixel size&position) - it has blurring at the right side

It seems bezier points introduce some inaccuracy, so even I got integral size&position for vector layer, I got little unexpected bluring, which is bad since I need to design some pixel perfect (sharp) icons.

[bkh]

Following screenshot presents two layer of 100x100px images zoomed 400% (pixel mode).



LAYERS:
(1) Square (vector with 4 straight line points, integral pixel size&position) - no bluring
(2) Rounded square/rect (vector with 8 bezier points, integral pixel size&position) - it has blurring at the right side

It seems bezier points introduce some inaccuracy, so even I got integral size&position for vector layer, I got little unexpected bluring, which is bad since I need to design some pixel perfect (sharp) icons.

Bezier points can be positioned in sub-pixel steps, so if your Bezier points are not aligned properly, there will be some anti-aliasing. It's usually advisable to align to a grid or to properly positioned guides to get precise results.

If this does not resolve your problem, it would be best if you posted your sample file as a zipped pld file.

Cheers,

Burkhard.

[ono]

Bezier points can be positioned in sub-pixel steps, so if your Bezier points are not aligned properly, there will be some anti-aliasing. It's usually advisable to align to a grid or to properly positioned guides to get precise results.

If this does not resolve your problem, it would be best if you posted your sample file as a zipped pld file.

I did pixel align (using 1px grid, as you suggested in other thread) all points and still I got redding (blur) at the right border, and only right border is affected (this may be suggestion where to find the bug, rounding error?).



Attaching the file. Please turn on Pixel Mode and zoom to 3200%, you will see clearly redding, at least this is the case at 16.11 on my Mac.

[bkh]

I agree with you that this seems a bug in PL (and possibly a fairly recent one - I should have noticed this when doing icons with PL 15.5 and various betas towartds PL 16). The pixels on the right hand side have the same colour (80 % red) as the others but 12.2 percent transparency. The same effect occurs if you draw a rectangle and turn the corner points into curve points (without changing anything else).

There is a similar effect if you add a 2 px outline - this time, the pixels on the lower edge are not fully opaque.

I guess that this is a case for the developers.

Cheers,

Burkhard.

[procyon]

Select the layer in question, choose the layer panel in the attributes dialog, in the antialias dropdown menu choose "never".
Is that what you want ?

[ono]

Select the layer in question, choose the layer panel in the attributes dialog, in the antialias dropdown menu choose "never".
Is that what you want ?

No, this is not the case of turning off antialiasing, which has nothing to do there, but having bezier curve points producing some inaccuracy at right edge of the shape. If I turn off antialiasing it is even worse, the right shape edge moves one pixel right. You can try yourself with attached file above.

[Martin Huber]

(2) Rounded square/rect (vector with 8 bezier points, integral pixel size&position) - it has blurring at the right side

Yes, the filling of a shape exceeds the right edge of the shape. I will look into that.

Martin

[ono]

Fixed in 16.40b6, Hooray!