Video over USB is a good new feature to add
I know you’re a bpp snob 
but honestly supporting larger displays in lower bpp (16 if required).
Also, making memory intensive thigns like double buffering, optional, would be nice. There are plenty of applications where you don’t need to scroll or worry about tearing, and where 16bpp is more than plenty
I’ll go a step further in saying that for many applications, higher refresh rate is much more important than higher bpp. A flashing image is unbearable to watch, or looks terrible in pictures if you only ever get half the picture and half black bars
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The latest version does allow lower color depth to increase display size / refresh rate - but currently only for Teensy 4…
I’m working on an Adafruit_GFX compatible Layer, mainly to get the nice Font support that’s now in Adafruit_GFX. If it’s fairly easy to add in support for lower bpp storage options and maybe disabling double buffering at the same time, I’ll do it!
I’ll try to make that consistent across platforms.
“I’m working on an Adafruit_GFX compatible Layer, mainly to get the nice Font support that’s now in Adafruit_GFX”
If I may, that’s exactly what SmartMatrix::GFX does (including more). Would you like to take/integrate the code in your tree?
TL;DR: SmartMatrix::GFX is FastLED backed Adafruit::GFX, so you have a 24bit framebuffer, you can use all the FastLED primitives on each pixel, use 16bit adafruit::GFX primitives on top, or use GFX with 24bits thanks to an override (a bit ugly to get around the fixed 16bit API, but it works in case of need).
Then I have that hack to also have the LEDMatrix API if you need extra stuff like screen transformations (it also supports native 24bit everything that GFX supports, and more)
Hi @marcmerlin, thanks for the reminder on SmartMatrix:GFX. I looked at it recently but didn’t realize a lot of the magic was in FrameBuffer::GFX and not the relatively simple SmartMatrix:GFX Library. I unfortunately wasn’t able to pull much from either library except for the idea of using passThruColor.
The teensy4 branch now has a new SMLayerBackgroundGFX class that is nearly fully backwards compatible with SMLayerBackground, but is Adafruit_GFX compatible and uses the Adafruit_GFX drawing functions for the more complicated drawing operations. (This was a lot of work! Mostly with dealing with multiple inheritance issues and obscure compiler errors)
Adafruit_GFX uses uint16_t (aka rgb16 or rgb565) for passing color, so it’s not good for high color depth graphics. If you call something like drawLine(rgb24) with SMLayerBackgroundGFX, the SmartMatrix Library wrapper function stores the rgb24 color until the operation gets down to a drawPixel() function, then it uses the rgb24 color for drawing instead of a uint16_t color with loss of fidelity. (Thanks Marc for this idea!)
Adafruit_GFX has more advanced support for drawing text to the screen, with support for large custom fonts, writing text to the display with a cursor and Arduino Print Library support, etc. That’s available now when using SMLayerBackgroundGFX. I haven’t converted the old SmartMatrix Library fonts yet, and the default fonts shipping with Adafruit_GFX are mostly larger fonts. For the time being, if you use the SmartMatrix Library setFont() method using one of the old built in fonts, it only uses a single 5 character tall font. You can use the Adafruit_GFX Libraries’ setFont function to choose a new font.
I can’t assume that everyone wants to use Adafruit_GFX or has it installed. For now, you need to add #define SUPPORT_ADAFRUIT_GFX_LIBRARY at the top of your Arduino Sketch before including any SmartMatrix Library headers. I can’t figure out a cleaner way to choose between having SmartMatrix Library look for “Adafruit_GFX.h” (and throwing an error if not found) and not supporting Adafruit_GFX at compile time. I think the default will be to support Adafruit_GFX with SmartMatrix Library 4.0, with an option #define to exclude the library.
There’s an Adafruit_GFX example. FeatureDemo also works with the new Layer by adding #define SUPPORT_ADAFRUIT_GFX_LIBRARY at the top and changing SMARTMATRIX_ALLOCATE_BACKGROUND_LAYER to SMARTMATRIX_ALLOCATE_BACKGROUND_GFX_LAYER
Still to come is Indexed and Scrolling Layers that support Adafruit_GFX. I also believe it should be possible to support rgb8 and rgb16 storage with this new Layer class, and I’ll look into that later.
Marc, I want to work with you on making sure this new layer has FrameBuffer::GFX compatibility.
Thanks for the update and progress. A few notes:
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yes Smartmatrix::GFX used to have all the code in it when I first wrote it, but it didn’t take me long to agree that 98% of the code was identical with FastLED::NeoMatrix, so I factored that out in the base class FrameBuffer::GFX
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The only tricky part in code I wrote, is this:
SmartMatrix_GFX/MatrixGFXDemo.ino at 7279a21fede3f5a972a206d3bb68f7fed1f02cae · marcmerlin/SmartMatrix_GFX · GitHub
because Smartmatrix uses templates, its objects can’t be passed to libraries, because well, templates suck for that
So, I’m forced to create the Smartmatrix background layer object, keep it in my code, I can’t pass it to the library, so instead I have to create a callback and send a pointer to that callback. -
Good that you were able to implement the 24bit passthrough hack. I can’t take credit for it, it came from the original Neomatrix code from adafruit
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for your last question, I think that your code partially implements what Framebuffer::GFX does (you’re probably missing XY() , some other helper functions in my lib, plus all pixel manipulation functions that come from the FastLED pixel container). This is the XY bit in case you’re curious:
Framebuffer_GFX/Framebuffer_GFX.cpp at f3713191d2911c7b7c2315a01f858236fe61b5c6 · marcmerlin/Framebuffer_GFX · GitHub
but honestly it’s mostly useful with complex arrays wired in “interesting” ways, so it’s unlikely to be useful to most RGBPanel users since the layout mapping you support in your base lib, is good enough for 99% of the cases
I’m not sure if there is any need to modify framebuffer::GFX though, basically it seems that you partially implemented it, built in in your library (I didn’t find which branch I should look into).
The way I understand what you have done, you offer compat with GFX, so that most users would be able to get GFX from your library without external libs.
If you’d like to check how well it works, try running MatrixGFXDemo :
on top of your new branch. The code should work is outside of the init section at the top.
Then, if people want FastLED CRGB container support and/or LEDMatrix compat support in parallel (for instance to run Mark Estes’ demos you’ve seen), they would continue to use SmartMatrix::GFX and Framebuffer::GFX as is, and those libs would ignore the new code you wrote since they implement a superset of it (basically they only use SmartMatrix to pass a pointer to a framebuffer to render, all the higher level stuff is ignored).
The only integration that could be added I suppose is some integration with smartmatrix layers, but I’ve never had the need for it, so I’ve never looked into it.
Does this kind of make sense? Did I miss anything?
It’s in the teensy4 branch.
Thanks for the pointers on getting our two libraries working together (or just leaving them alone for now). I’ll come back to this after I get scrolling and indexed color working.
Thanks.
I forgot to mention that one big plus of framebuffer::gfx for me is that I can now compile and run all my code on linux and render it on my laptop with ASAN (memory checker) and gdb.
This is life changing
(also, the save, compile run cycle is so much faster too)
Here’s an update on the new Adafruit_GFX compatible layers: Adafruit_GFX Compatible Layers - Modern Font Support coming to SmartMatrix Library 4.0 - #2 by marcmerlin
I’m trying to keep the discussion on Adafruit_GFX and the new layers in one place for now, so I’ll probably update on Framebuffer::GFX compatibility there when I get to it. I didn’t expect this layer update to take most of my free time for over a week, so I haven’t gotten to all the things I wanted to do with the new layers like smaller rgb storage, and Framebuffer::GFX compatibility, and I’ll probably have to put those on hold for at least a bit as my SmartLED Shield for Teensy 4 campaign is ending and I’ll need to focus on manufacturing the shields.
We have two threads talking about the Teensy 4 and SmartLED Shield for Teensy 4, I’m going to be posting to this one as there’s more people following it).
I just received my new SmartLED Shields for Teensy 4 and am looking forward to using them with Fadecandy! Please keep us updated, @Louis on your progress!
Ready to try! See notes in fadecandy/server/README.md
And for completeness:
More later
SmartLED Shield for Teensy 4 is available from distributors worldwide now, see the list here: SmartMatrix - Shop
DO you know when the orders placed through crowdsupply will be shipping? I cant wait!
Crowd Supply orders should have shipped already, unless you just placed it recently. I don’t have good visibility into exactly what has shipped, you should contact Crowd Supply to get an update on your order if it’s been more than a few days since you placed it. Hope you get it soon!
Thank you Louis. Its been several weeks. Ill hit them up.