Background Image Extra Settings

[ungodlyaura]

-I would like to be able to set the size of an image, just maybe like size_scale = 1 setting
-Image offset amount
-A spacing/padding to the background could be nice but not necessary (along with a default background color setting and/or option to add a second background image to go under the first one wherever transparent/padding is)
background sizing

couple extra things I'm not making another Issue post for:
-zoom min/max setting
-looped screen edges option + a screen size limit

[malbiruk]

Thanks for the detailed write-up! Let me go through these.

Background sizing / offset / padding / default color / second image

The built-in background is deliberately minimal, but all of this is doable today by layering. driftwm's background renders above any wlr-layer-shell Background surface, so: run a normal wallpaper daemon (swaybg, swww, mpvpaper) underneath for a base color or second image, then put a transparent PNG (type = "tile") or a shader with transparent_shader = true on top -- transparent or padded areas reveal the layer below. For scaling/offsetting an image with real control, a type = "shader" with a texture samples it in GLSL. That gets you size/offset/padding/color from tools built for it, no per-option knob. See docs/shaders.md.

Image offset -- home position

The cleanest form of "offset" to me is a configurable home position. The canvas home is hardcoded to (0,0) today; I'd like to make it configurable, so the compositor starts the camera there and mod+a (home-toggle) returns to it. Most useful with big tiled/gigapixel wallpapers, so you start on the interesting part of the image instead of a center.

zoom min/max

• min -- currently dynamic, derived from your window layout so you can always zoom out to see every window plus some margin. I'll add an optional absolute override for zooming out further (e.g. to see a whole big wallpaper even with no windows out there).
• max -- capped at 1.0 for now. Zooming past 1.0 (magnification) is Magnifying zoom #37 -- a state machine where 1.0 is a boundary you cross by releasing and starting a new gesture. A configurable max ships with that.

Looped screen edges + screen size limit

• Looped/toroidal canvas (pan off one edge, appear on the other) -- passing on this, same as Magnifying zoom #37. Wrapping the coordinate space (windows drawn twice at seams, snapping/navigation/hit-testing all wrapping) is a lot of complexity for marginal gain.
• Screen size limit -- this one I've come around on. Planning an optional canvas size (off by default -- infinite unless you set it) that keeps windows contained so they can't drift off into nowhere, with a visible boundary outline.

Appreciate the thoughtful suggestions!