Just pointing out an alternative method

vajahath commented 8 months ago

First, thank for your incredible work ⭐

I could keep this myself without bothering you. But seeing #64 and many others, I thought I could just open this issue.

I made a fork: https://github.com/vajahath/image-thermal-printer

What it basically does is convert the "thing to print" into an image (or HTMLCanvasElemet) and use the https://github.com/seokju-na/react-thermal-printer/blob/main/packages/printer/src/commands/image.ts image command on it.

So far, it is working nice-ish (some tweaks needed here and there)

I converted my div into canvas (https://www.npmjs.com/package/html-to-image#toCanvas). Then printed it using the above command. This gave me unlimited customization.

(the printer I'm using is very old and of low quality - hence some lines segments are lost) PXL_20240224_181001863 MP

Because the printers are generally having low resolution, serif typeface may not be a good choice. I prefer sans serif typeface. Roboto is a good choice. (Noto as well). Any font that claims to work well in low-res could be a good choice.

Some advantages I found:

Alignment: This is a solved problem in html. With now we having the container-queries, we can design a div the way we want.
Tables: html tables adjust themselves
Responsive: Thermal printer comes in many width - 2 inch (my case), 3 inch. With the right css you can target any number of widths.
Tiny and simplified code (mainly image manipulation is only required)
Framework agnostic.

Cons:

Need to fiddle around the printer dpi (mine is 200) and possible print widths.

This issue was to inform you an alternative method. Feel free to close this issue whenever you wish.

vajahath commented 8 months ago

Also the https://en.wikipedia.org/wiki/Atkinson_dithering claims to provide better contrast than Floyd–Steinberg. Its integration may also provide slightly better results - just pointing out.

m90khan commented 5 months ago

Good work. I do not have any thermal printers around at the moment. so that means it can work with any thermal printer brand. It does not have to be Epson or Star. ?

@vajahath

vajahath commented 4 months ago

Thank you. Afaik, the printer itself doesn't have to be from Epson or star. Most printers I encountered (a fairly small number) do follow the Epson/star protocol. So you should be good to go. 🤞

m90khan commented 4 months ago

Thanks for your reply. helpful :)

seokju-na / react-thermal-printer

Just pointing out an alternative method #70