From 3d1f4834acded22ba4e75ce0ab0c7456a767eebd Mon Sep 17 00:00:00 2001 From: "Danilo M." Date: Thu, 29 Oct 2026 13:09:17 +0100 Subject: wallpaper: a shuffle bag for the engine's order Each round shows every hearted wallpaper once, in random order, so no picture is skipped or doubled within a round. A reshuffle never opens with the picture on screen, so the same wallpaper cannot appear twice in a row across the round boundary. Co-Authored-By: Claude Haiku 5.5 --- desktop/modules/appearance/Shuffle.js | 35 +++++++++++++++++++++++++++++++++++ 1 file changed, 35 insertions(+) create mode 100644 desktop/modules/appearance/Shuffle.js (limited to 'desktop/modules/appearance/Shuffle.js') diff --git a/desktop/modules/appearance/Shuffle.js b/desktop/modules/appearance/Shuffle.js new file mode 100644 index 0000000..7e5cf16 --- /dev/null +++ b/desktop/modules/appearance/Shuffle.js @@ -0,0 +1,35 @@ +.pragma library +// Copyright (C) 2026 Danilo M. +// +// This program is free software; you can redistribute it and/or modify +// it under the terms of the GNU General Public License version 2 as +// published by the Free Software Foundation. +// +// This program is distributed in the hope that it will be useful, +// but WITHOUT ANY WARRANTY; without even the implied warranty of +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +// GNU General Public License for more details. + +// The wallpaper engine's order, tested by test_shuffle.js under node: a +// shuffle bag. Each round shows every path once in random order, and a new +// round never opens with the path on screen, so a reshuffle cannot show the +// same picture twice running. + +// The next path and what is left of the round. `list` is what may be shown +// now, so a heart removed since the last draw drops out of the bag; `last` is +// the path on screen. pick is "" for an empty list. +function draw(list, bag, last) { + let left = bag.filter(p => list.indexOf(p) >= 0); + if (left.length === 0) left = shuffled(list, last); + return { pick: left.length ? left[0] : "", bag: left.slice(1) }; +} + +function shuffled(list, last) { + const a = list.slice(); + for (let i = a.length - 1; i > 0; i--) { + const j = Math.floor(Math.random() * (i + 1)); + const t = a[i]; a[i] = a[j]; a[j] = t; + } + if (a.length > 1 && a[0] === last) { const t = a[0]; a[0] = a[1]; a[1] = t; } + return a; +} -- cgit v1.2.3