honey_the_codewitch

Maybe i didn't publish a specific teensy article? I thought i did. hmm. oh well, it's been years and my memory is dodgy on a good day. in any case, the code is largely the same, so that article covers what runs on both of them, except for the...

Sure. But usually you have to make that choice during the design cycle, by which i mean you typically can't just pick and choose. You're either backbuffering or not, so generally you don't have the luxury of deciding for each individual draw...

There probably was at one point, on codeproject, where i produced an article about it. However, codeproject went dark (again) recently. I suppose I could rebuild the project. I have at least most of the components around here somewhere still...

The best thing as always is to profile. The one thing to remember when you work your figures though is (a) to use DMA you MUST build a bitmap, even it's all one color. (b) to use DMA *effectively* you really should keep two backbuffers such that...

I'm not sure how many pins the Teensy can control with DMA but NXP chips are generally pretty capable, so my guess is that it is possible, but non-trivial. The ESP32s have support for DMA with i8080 parallel but i've not seen anything for the...

That's essentially my point about the "data density" of transactions. Drawing bitmaps allows you to always fill your entire transaction window with data. You're dramatically cutting down on the total number of SPI transactions that you need, and...

You seemed to understand, but just in case: I mean writing to bitmaps, writing those to the display. Critically, using DMA to do so, so you get the 20%-30% throughput increase as well, and combining that with a dirty rectangle algorithm so you're...

Adding, the first rendition of my graphics library for embedded - htcw_gfx 1.x - used direct writes, including a bunch of tricks to speed those up. It wasn't fast enough. In 2.x I got rid of all that for performance reasons, and now I use my...

It's an extreme case but it's also a contrived case. In real world applications, you'll find things like LVGL that use backbuffering can paint faster than similar code using TFT_eSPI because of the way applications typically operate in terms of...

I just came here to say if you're looking for maximum performance, direct SPI writes are not the way to go. What you want to do is backbuffer to a bitmap, and then use DMA to transfer bitmaps to the display. The reason is simple. It's math. The...