Oh, and one more thing... Gemma & Trinket dimming Oh, and one more thing.

Archive FastLED Archive
,
1

Oh, and one more thing… Gemma & Trinket dimming

Oh, and one more thing. As of the full V2 release of FastLED tonight (see previous post), the FastLED master brightness/dimming function, FastLED.setBrightness(…), now works on all supported platforms, including ATtiny85-based Gemma and Trinket boards, even the slower 3.3v 8MHz models. This will be of particular interest to people making battery-powered projects with Gemma and Trinket where they want an easy way to keep power usage under control.

As always, using the FastLED master brightness control does not alter the contents of your “leds[…]” array at all, nor does it slow down your animation or consume additional CPU power; it’s as close to “free” as anything ever is.

Mad props to @Daniel_Garcia for some truly inspired and clever wizardry to make this work on ATtiny chips that have no hardware multiply capability, even the “half-speed” (8MHz) boards. Many people said this was completely impossible, and it was. Until Dan did it.

Enjoy!

2

I am interested in looking at this code. I am wondering how efficient it is. I have wanted to start a whole project where i Just hue HSV in stead of RGB in the array. Then just convert it all right before I show. There are all sorts of new functions to go back and forth with the new library but I would think doing all those conversions eats up a lot of unnecessary cycles? What do you think?

3

It’s a great idea, right? Dan and I have this as a long-term goal: to allow the led buffer to be 100% HSV, and still have it drive an RGB LED strip in realtime. We believe this is probably doable on ARM platforms, but dubious about its feasibility on AVR platforms.

We’re already doing one realtime transform (master brightness control), but colorspace conversions are much more computationally costly than that.

But, again, it’s a great idea to shoot for, eh?