Some suggestions

[upbeat59]

Hello,
Here are 2 suggestions that I think would improve the app :

• Once the app is active, prevent the screen to fade out. This is something definitly possible on android Apps since "Screen Alive" (app that I use only for Howl) can do it. I understand some users probably starts Howl and their favorite program and that's it, but it's very annoying to have the screen fadeing out quickly when you are constantly playing out with effects and such.
• Allow to have some pause (eg: few ms to few seconds) between effects in generator mode.

Cheers.

[Amethyst-Sysadmin]

Thanks for the suggestions! I've made a change in 0.9.2 that should keep the screen active while content is playing. That's something I intended to do earlier, but forgot about, since I have a very long screen timeout set on my own phone.

The screen will be allowed to sleep again (after the normal delay) once playback stops. Hopefully that approach is convenient for users - for example if somebody stops playback via the Kodi add-on, then their phone screen should automatically go to sleep after a while.

Adding pauses between changes in the generator probably isn't simple to currently do in a way that makes sense to users, since many parameters shift their values around over time (only the shapes change instantly). If I get around to updating the generator with some new ideas at some point, I might take a look at it then (it hasn't been touched much lately as I've been focusing on other areas of the app).

[upbeat59]

Thank you for the "screen stay active" feature. It's very useful. I had to use the "Screen Alive" app everytime (and needed to revert settings after each use).

Generator : I think a nice feature would be to have control over some of the settings of the generator over the time. For example the speed, power and frequency parameters (as seen in Channel A/B) could be changed automatically using another function (eg: a sine, triangle, trapezoid or square wave). Applying those functions would be same result as manually adjusting the slides over the time. For example if you set a sine on "Speed" parameter (with amplitude = 0.2 and frequency = 5 seconds), the speed will increase/decrease slightly (-0.1 +0.1 ) over 5 seconds. That would add some variety to the existing generator modes. Like something that accelerate faster and faster to then decrease.

Because square wave with high amplitude is basically a on/off switch, using this on power could be used to have some pause as well (as suggested in my previous message). This assume you have a 50% on / 50% off only. This is less flexible than having an arbitrary pause (but far easier to implement).

[upbeat59]

Let's dream for a second : the most flexible option would be some kind of editor where would could add some nodes (eg: wave generator, constant value, ...) and connect them together (similar to audio or shader processing). Each node is configurable to some degree, and has inputs and outputs. I understand this is a LOT of work but this would be awesome.

Another (cheaper) alternative would be an expression evaluator where you could write a math expression that control the device output(s). The goal is not to generate the output pulses directly. UI side, only thing needed for the expression evaluator is a huge text area. Great patterns could easily be shared between via a link (that would replace expression inside Howl, once opened). I know how to write a math expression evaluator/parser from scratch. It's actually fairly easy once you know a few tricks. If you ever wanted to go that route, feel free to contact me.

[Amethyst-Sysadmin]

That approach would be very flexible. But it's more difficult to implement, and would probably be incomprehensible to most users of the app!

It's actually already pretty easy to do expression based output as a developer using the framework I provided for activities. So if you want to play around with that, I would suggest building the app yourself and implementing a custom activity instead. ChaosActivity (in Activity.kt) is helpful as a simple example. The key functions to implement are runSimulation, where you can do your maths (this gets passed a time delta since the last call). And getPulse, where you just return the output you want. Any new activities also need adding to the big list at the top of "ActivityHost.kt" so that they show up for selection (just copy how the others are defined).

Another (maybe simpler) way to make an expression based pattern without building the app is to generate an HWL file. This gist shows a very simple example of a basic on/off pattern. But of course you could easily have the values follow something like a sine function (or any other kind of function you can think of) instead. It's slightly less precise since with HWL files you're just using the output from your function at 1/40th second intervals rather than the continuous function itself. But I think that should be sufficient to get good results.