|
|
|
You don't trust Mr. Google? 
The less you need, the more you have.
Even a blind squirrel gets a nut...occasionally.
JaxCoder.com
|
|
|
|
|
|
Me I trust Mr. Ed[^]
The less you need, the more you have.
Even a blind squirrel gets a nut...occasionally.
JaxCoder.com
|
|
|
|
|
Even the back end of Mr. Ed is more trustworthy than many things these days!
|
|
|
|
|
Mr. Ed's back end and Facebook look about the same to me.
The less you need, the more you have.
Even a blind squirrel gets a nut...occasionally.
JaxCoder.com
|
|
|
|
|
I disagree. Mr Ed's back end produces useful manure.
Keep Calm and Carry On
|
|
|
|
|
Agree and Facebook useless manure
The less you need, the more you have.
Even a blind squirrel gets a nut...occasionally.
JaxCoder.com
|
|
|
|
|
I agree with Dilbert. I frequently tell people to do their own research on contentious topics.
|
|
|
|
|
That's fine as long as you don't confuse "search" with "research".
I think that, as long as you just search the Internet or libraries or any other source of knowledge, you are just going to find facts or opinions of other people. If you want to find something new you have to analyze, experiment, test hypothesis and all the other boring stuff commonly referred as science
Back in the day, learned men would argue if more than one angel can be in the same place. The more things change, the more they stay the same.
Mircea
|
|
|
|
|
The man I work for right now thinks he is and expert, when it comes to what I do. He couldn't find his A** with a flashlight and a road map.
I am living in micro-management hell. Perhaps for not much longer. I may be looking for work by Monday afternoon.
|
|
|
|
|
I see a few new faces this week and I must say I'm disappointed.
No need to get my coat - I never took it off.
To err is human. Fortune favors the monsters.
|
|
|
|
|
Tarring and feathering is too good for you! 
Freedom is the freedom to say that two plus two make four. If that is granted, all else follows.
-- 6079 Smith W.
|
|
|
|
|
That one gave me a lift!
If you can't laugh at yourself - ask me and I will do it for you.
|
|
|
|
|
There's nothing quite like a library where you can write graphics drawing code once and run it on any display be it monochrome, e-paper, color, etc.
In order to enable this I dither monochrome to give me grayscales. As far as the rest, I do automatic color conversion where necessary.
I'm finding myself greatly amused by running an alpha blending and JPG loading demo on a 128x64 monochrome OLED display.
The funny thing is, it's actually at least viewable - even the alpha blending - you can at least see what it's trying to do, and that's pretty good when you are overlapping and blending random shapes of random colors and opacities.
I may have taken device independence a little far.
To err is human. Fortune favors the monsters.
|
|
|
|
|
Device independence: Hummm. Long time goal in computer graphics. CORE, PHIGS, GKS, maybe more but I haven't kept up.
Does the display device declare what it is, what it can display? etc.
If so then display independence ends at the end of that list?
If not does software have tuning to adapt with user intervention or without?
What you have done is impressive especially for e-paper displays (tricky hardware) but, device independence is a carrot.
|
|
|
|
|
Well, it's not resolution independent. You still specify everything in pixels, but you can size things relative to the dimensions() of your draw target.
The key here though is automatic conversion of pixel formats. You can draw any type of pixel to any draw destination. That means, for example, if you get 24-bit Y'CbCr pixels, like from a JPG, you can write them out to a 16-bit RGB display transparently. Same with going from color to monochrome or grayscale. If you add an alpha channel to the pixel, it will do alpha blending on the draw target with whatever color was at the current location on the draw target. If you draw to a device with a palette it will do color matching to that palette.
Basically, you don't have to worry about pixel formats. You can just draw. You can just load jpgs. You can just choose any of the colors from the X11 color palette, or make your own.
The upshot here is you can write your drawing code once, and run it on any display.
To err is human. Fortune favors the monsters.
|
|
|
|
|
Understood. The pixel pipeline is sort of the lowest common denominator for displays. A first key measure of independence. Good job.
Some graphics history. In late 70's, my first computer graphics device for which I had to write a library was the Tektronix 4010. It was just an electronic etch-a-sketch. No real pixels just draw lines with a beam of light. It was a very inexpensive way to do graphics because no refresh cycle was required to keep the screen lit up.
Then on to Silicon graphics, etc.
|
|
|
|
|
I've heard of those. They're like plotters, basically, no? Cool tech, even if it's a bit dated.
The code in this article:
Using GFX in PlatformIO[^]
Yields this on different displays (e-paper among them but I didn't record that one and it doesn't animate)
Same demo code running on 3 different displays - GFX : esp32[^]
like between 80% and 90% of the actual lines of code for drawing are the same. The most major change I did was using a different JPG for color displays than ones that aren't.
To err is human. Fortune favors the monsters.
|
|
|
|
|
yes, they were. For physical line plotters, it was optimal to keep the pen down as long as possible from line to line, so one sorted the lines to connect them as long as possible. Although line plotters are not common these days; it's quite a sight to see a high speed line plotter in action; a real pen on a giant piece of paper, both moving all over the place, like there was no tomorrow.
|
|
|
|
|
I haven't seen a monochrome monitor in years. Where do you get them?
blind squirrel
|
|
|
|
|
|
Dithering to produce grayscale when the total resolution is 128*64 sounds somewhat limited in my ears
This kind of display is fair enough for embedded devices (which, I understand, is exactly what you are making) for simple text messages, and very simple graphic indications. To me, a 'binary' (no grayscale) (max) 16*8 chars text display the size of your thumbnail is not a 'monitor'. My microwave, or my baking oven, doesn't have a 'monitor', but a display. (I do notice, however, that the term 'monitor' was introduced by Slow Eddie, not by you!)
Another side is that if you buy something sold as an 'Oled LCD LED' display, several spelling and grammatical errors, 'ar duino' referred to several times, as well as du-pont, inconsistent dimension data, quite meaningless disclaimer about US power plugs, and why is a 40-pin flat cable included with a device that provides 4 control lines? ... then you know approximately what you will get. It is not quite at the same level as buying components from an internationally renowned manufacturer with a strong support department.
It still might be a good buy, considering the price, but I would always check price and functionality against what is offered on Mouser.com. You'll find a quite large selection of displays in this class, and the web interface provides a filtering mechanism that is at least tolerable. Usually, a product sheet link is provided. Mouser is primarily aimed at professional customers buying lots of hundreds or thousands, so if you order one component at a time, P&H may be excessive. But usually, you can buy one at a time (with the obvious exception of e.g. products delivered on a reel - you can buy one reel at a time, but not having a single component cut from a reel).
I'd recommend checking Mouser if you are in search of components. Taking a look at the web site costs nothing (except your time).
|
|
|
|
|
I wasn't endorsing that purchase - it was merely the first link I found that displayed the device prominently and had an option to buy.
The dithering is primarily so you can do things like load JPEGs onto the display, which may even be good for an IoT gadget because it means you can put the logo on the screen, but yes it is limited.
I should add, I'm familiar with mouser, but i tend to use digi-key more just because i have a client who prefers them.
To err is human. Fortune favors the monsters.
modified 13-Mar-22 18:02pm.
|
|
|
|
General 
News 
Suggestion 
Question 
Bug 
Answer 
Joke 
Praise 
Rant 
Admin 
Submit an article or tip
