Show HN: Inkwash, a watercolor sketching app and explanation

Posted by Yenrabbit 3 days ago

I've made a drawing app based on my physical sketching practice, using fluid sim and some shader tricks to mimic watercolor-style ink washes. Best used on iPad or with a drawing tablet. The linked article shows how the core engine works, with plenty of little interactive demos. It was fun to make, sharing in hopes others find it fun too :)

Comments

Comment by armcat 44 minutes ago

As an amateur watercolour artist (shameless plug: https://www.instagram.com/p/DBlKG5cMPxa) I have to say the feeling your made with this wash is gorgeous. Back in the analogue world - paper grain and type/brand has a lot to do with it. Watercolour is really about unpredictability - it's about taking advantage of this unpredictability in terms of how the water travels down the grain and the impact that it makes, combined with light/shadow and "confidence" the artist brings with the brush. So of course it's never going to be truly transferrable digitally, but I still love the work you put into this.

Comment by vunderba 3 days ago

Nice visualizations - have you tried Rebelle? They have an online version that lets you play with the watercolor/brushes of the painting software so you can see the colors drying on the canvas.

https://www.escapemotions.com/experiments/rebelle/index.php

Comment by cam_l 12 minutes ago

I never got into rebelle, though this demo is pretty cool.

I used to use expressii, and always thought it was one of the most under rated painting apps. Has a very natural feel to it.

https://www.expresii.com/

Comment by vunderba 7 minutes ago

That's super neat looking - I really like the demonstrations of Chinese calligraphy with the brushes as well.

Comment by Yenrabbit 2 days ago

Oooh yeah I forgot how incredible that was! They really put care into how the pigments mix and move. I used to love watching timelapses of people doing art in rebelle.

Comment by BugsJustFindMe 1 hour ago

The examples display a degree of vorticity that I have never seen in real life watercoloring. They look great superficially, but they look super weird at reasonable inspection. Water on paper does not flow nearly so freely.

Comment by the-mitr 13 minutes ago

It is very fun and aesthetically pleasing also, great job.

Comment by ameon 3 days ago

looks beautiful! i wanted to bookmark it because sometimes i need to explain some geometry to my son, and i have to download some sketching app each time, but with this I could just open and paint. There's one problem however. When on mobile, the page does not hid the control panel (mode, ink, etc) and it takes a large portion of the screen.

Comment by Yenrabbit 2 days ago

Ah yeah that's not ideal, fixed. I like the menu sticking around on iPad, but it now gets out of the way on smaller phone screens. Thanks for the reminder, I'd been meaning to do this! (Also, tldraw.com is fantastic for quick+easy diagrams and works great on mobile if you want a better whiteboard that isn't so art-focused :) )

Comment by levi840714 1 day ago

The interactive explanation is the best part — being able to scrub the sim while reading the writeup made it actually click.

Comment by ahmd-sh 1 hour ago

This is so satisfying! I love how the blending looks and fluidly works.

I've always admired watercolor animations (especially the ones in the video game Gris) and wanted to bring that to the web, but didn't know how.

Comment by esychology 1 hour ago

This is awesome! The strength of the flow/advection is a bit too high imo. Maybe increase some viscosity parameter?

Comment by pinstripes 51 minutes ago

I like that adding pen strokes to a watery section continues to blend in. Ima copy you now and become a cool art person

Comment by maarudth 3 days ago

i like it a lot. looks beautiful

Comment by Yenrabbit 3 days ago

Thanks :)