Easy way to interact with shader params using the GUI

[JoshuaBatty]

At the moment, each shader has a params struct that contains all of the shaders tweakable parameters. For example, the gilmore acid shader has a params struct like below:

struct Params {
    speed: f32,
    displace: f32,
    colour_offset: f32,
    grid_size: f32,
    wave: f32,
    zoom_amout: f32,
    rotation_amount: f32,
    brightness: f32,
    saturation: f32,
}

It would be nice to be able to tweak these values during the show. Currently, the way i've mapped the midi controller is I can tweak the 2 most fun params for each shader. In this instance though, the gilmore acid shader has 7 more variables that aren't able to be tweaked, and since my mac cant hot-reload I will be unable to 'live code' during the performance.

I was thinking it would be awesome if somehow, when a shader is selected via the Drop Down Menu, the params associated with that shader showed up as sliders.... I haven't been sure about the best way to auto-populate this with out some crude hand coded solution for each shader... maybe there is a nice dynamic way of achieving this?

GUI Example (would be nice is the sliders were named after the params they were controlling)

MIDI MAPPINGS

[mitchmindtree]

You should be able to do this pretty easily by having a struct somewhre which has each of these params structs stored in it (this will probably have to be in the shaders_shared crate so it can be passed into the Uniforms struct), then create an enum or index or something that allows you to pick between which ones you currently want to edit. Then the GUI just shows sliders for the currently selected one? I haven't looked too closely yet so this is just off the top of my head!