Jump to content
Sign in to follow this  

Brush behaviour

Recommended Posts

Affinity Designer
Windows 10 (spec probably irrelevant here)

So, I'm identifying this as a bug, but there may be other opinions about the way this works. Ultimately, fixing this will have an affect on older designs that use brushes.

 I've made a test brush pattern within designer as a PNG, and exported it (it's 200 pixels height and 568px width). So I then bring this in as a Textured Intensity Brush with a width of 200px to match the height of the exported brush image (black rectangle with white stripes). I then draw a path over the top widthwise of my original brush and assign my new brush - see attached image - brush is in red on the highlighted straight two node path. IMHO I'd expect that brush to be aligned perfectly with the original design now being that the length of the line is the same as the width of the rectangle, and the height is the same. So, heightwise it's fine, but widthwise it's off by a long way. More interestingly is when I use the node tool and drag the end node to the right the pattern will stretch, but then suddenly snap back to allow another repetition to fit in. This then looks very squashed. I would expect the behaviour along a path like this to be consistent - certainly on a straight line, so I think this is highlighting a problem with the maths algorithym - it looks like modulus is bieng used with the repeats but in a way that's not quite right. I'd expect that behaviour to be consistent from the start of the line running to the end, so altering points on the end of a long path with lots of nodes doesn't affect the brush pattern at the start end of the line. It should be working on length of line based from the start node. This is not whats happening, and thus why I'm reporting it as a bug. Brush settings are Width: 200px, size variance: 0%, Opacity Variance: 0%, default pressure curve, Body: Repeat, Head Offset: 0px, Corners: Fold (I tried them all here), Tail Offset: 568px (with a brush graphic width of 568.0px).

I've just tested a thought I had and discovered that changing the stroke to Butt Cap makes the alignment on the image below perfect, however pulling out the node with that mode on still stretches the brush pattern a lot and then snaps back when there's more than enough space for two patterns to fit. My expectation would be that it would simply add pattern onto the end of the first pattern and allow it to get cut off at the end of the path, rather than stretching one pattern length until there's room for two pattern lengths. It's hard to describe, but it looks to me like the algorythm is working the wrong way round with the modulus. So if the line is 1.5 pattern lengths long, I'd expect it to be using two pattern lengths and cropping the second pattern halfway along. That way the start of the line would always look the same when you adjust the end point.


Share this post

Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
Sign in to follow this  


Important Information

These are the Terms of Use you will be asked to agree to if you join the forum. | Privacy Policy | Guidelines | We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.