From c3be5665740fb0100ee7d6d74282e933110a7141 Mon Sep 17 00:00:00 2001
From: Emil Ernerfeldt <emil.ernerfeldt@gmail.com>
Date: Wed, 2 Feb 2022 17:09:36 +0100
Subject: [PATCH] egui-winit: Automatically detect and apply dark or light mode
 (#1045)

---
 Cargo.lock              | 581 +++++++++++++++++++++++++++++++++++++++-
 eframe/CHANGELOG.md     |   1 +
 egui-winit/CHANGELOG.md |   1 +
 egui-winit/Cargo.toml   |   3 +-
 egui-winit/src/epi.rs   |  23 +-
 egui_glium/CHANGELOG.md |   1 +
 egui_glow/CHANGELOG.md  |   4 +-
 egui_glow/Cargo.toml    |   2 +-
 8 files changed, 601 insertions(+), 15 deletions(-)

diff --git a/Cargo.lock b/Cargo.lock
index 6158dedf..535638c8 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -39,6 +39,12 @@ version = "1.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "aae1277d39aeec15cb388266ecc24b11c80469deae6067e17a1a7aa9e5c1f234"
 
+[[package]]
+name = "ahash"
+version = "0.4.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "739f4a8db6605981345c5654f3a85b056ce52f37a39d34da03f25bf2151ea16e"
+
 [[package]]
 name = "ahash"
 version = "0.7.6"
@@ -81,6 +87,98 @@ version = "1.0.52"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "84450d0b4a8bd1ba4144ce8ce718fbc5d071358b1e5384bace6536b3d1f2d5b3"
 
+[[package]]
+name = "async-broadcast"
+version = "0.3.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "90622698a1218e0b2fb846c97b5f19a0831f6baddee73d9454156365ccfa473b"
+dependencies = [
+ "easy-parallel",
+ "event-listener",
+ "futures-core",
+]
+
+[[package]]
+name = "async-channel"
+version = "1.6.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2114d64672151c0c5eaa5e131ec84a74f06e1e559830dabba01ca30605d66319"
+dependencies = [
+ "concurrent-queue",
+ "event-listener",
+ "futures-core",
+]
+
+[[package]]
+name = "async-executor"
+version = "1.4.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "871f9bb5e0a22eeb7e8cf16641feb87c9dc67032ccf8ff49e772eb9941d3a965"
+dependencies = [
+ "async-task",
+ "concurrent-queue",
+ "fastrand",
+ "futures-lite",
+ "once_cell",
+ "slab",
+]
+
+[[package]]
+name = "async-io"
+version = "1.6.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a811e6a479f2439f0c04038796b5cfb3d2ad56c230e0f2d3f7b04d68cfee607b"
+dependencies = [
+ "concurrent-queue",
+ "futures-lite",
+ "libc",
+ "log",
+ "once_cell",
+ "parking",
+ "polling",
+ "slab",
+ "socket2",
+ "waker-fn",
+ "winapi",
+]
+
+[[package]]
+name = "async-lock"
+version = "2.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e6a8ea61bf9947a1007c5cada31e647dbc77b103c679858150003ba697ea798b"
+dependencies = [
+ "event-listener",
+]
+
+[[package]]
+name = "async-recursion"
+version = "0.3.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d7d78656ba01f1b93024b7c3a0467f1608e4be67d725749fdcd7d2c7678fd7a2"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
+[[package]]
+name = "async-task"
+version = "4.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "677d306121baf53310a3fd342d88dc0824f6bbeace68347593658525565abee8"
+
+[[package]]
+name = "async-trait"
+version = "0.1.52"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "061a7acccaa286c011ddc30970520b98fa40e00c9d644633fb26b5fc63a265e3"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
 [[package]]
 name = "atk-sys"
 version = "0.14.0"
@@ -246,6 +344,12 @@ version = "1.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "c4872d67bab6358e59559027aa3b9157c53d9358c51423c17554809a8858e0f8"
 
+[[package]]
+name = "cache-padded"
+version = "1.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c1db59621ec70f09c5e9b597b220c7a2b43611f4710dc03ceb8748637775692c"
+
 [[package]]
 name = "cairo-sys-rs"
 version = "0.14.9"
@@ -263,7 +367,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "bf2eec61efe56aa1e813f5126959296933cf0700030e4314786c48779a66ab82"
 dependencies = [
  "log",
- "nix",
+ "nix 0.22.0",
 ]
 
 [[package]]
@@ -436,6 +540,15 @@ dependencies = [
  "memchr",
 ]
 
+[[package]]
+name = "concurrent-queue"
+version = "1.2.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "30ed07550be01594c6026cff2a1d7fe9c8f683caa798e12b68694ac9e88286a3"
+dependencies = [
+ "cache-padded",
+]
+
 [[package]]
 name = "console_error_panic_hook"
 version = "0.1.7"
@@ -659,6 +772,22 @@ version = "0.2.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "b365fabc795046672053e29c954733ec3b05e4be654ab130fe8f1f94d7051f35"
 
+[[package]]
+name = "dark-light"
+version = "0.2.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0a76de8354e3935082b341ac29aeff1d05dd14eab64d67ffce4c2f6af06cdb2b"
+dependencies = [
+ "dconf_rs",
+ "detect-desktop-environment",
+ "dirs",
+ "objc",
+ "rust-ini",
+ "winreg",
+ "zbus",
+ "zvariant",
+]
+
 [[package]]
 name = "darling"
 version = "0.13.1"
@@ -694,6 +823,12 @@ dependencies = [
  "syn",
 ]
 
+[[package]]
+name = "dconf_rs"
+version = "0.3.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7046468a81e6a002061c01e6a7c83139daf91b11c30e66795b13217c2d885c8b"
+
 [[package]]
 name = "deflate"
 version = "0.8.6"
@@ -704,6 +839,23 @@ dependencies = [
  "byteorder",
 ]
 
+[[package]]
+name = "derivative"
+version = "2.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "fcc3dd5e9e9c0b295d6e1e4d811fb6f157d5ffd784b8d202fc62eac8035a770b"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
+[[package]]
+name = "detect-desktop-environment"
+version = "0.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "21d8ad60dd5b13a4ee6bd8fa2d5d88965c597c67bce32b5fc49c94f55cb50810"
+
 [[package]]
 name = "directories-next"
 version = "2.0.0"
@@ -714,6 +866,26 @@ dependencies = [
  "dirs-sys-next",
 ]
 
+[[package]]
+name = "dirs"
+version = "4.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ca3aa72a6f96ea37bbc5aa912f6788242832f75369bdfdadcb0e38423f100059"
+dependencies = [
+ "dirs-sys",
+]
+
+[[package]]
+name = "dirs-sys"
+version = "0.3.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "03d86534ed367a67548dc68113a0f5db55432fdfbb6e6f9d77704397d95d5780"
+dependencies = [
+ "libc",
+ "redox_users",
+ "winapi",
+]
+
 [[package]]
 name = "dirs-sys-next"
 version = "0.1.2"
@@ -740,6 +912,15 @@ dependencies = [
  "libloading",
 ]
 
+[[package]]
+name = "dlv-list"
+version = "0.2.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "68df3f2b690c1b86e65ef7830956aededf3cb0a16f898f79b9a6f421a7b6211b"
+dependencies = [
+ "rand",
+]
+
 [[package]]
 name = "downcast-rs"
 version = "1.2.0"
@@ -773,6 +954,12 @@ version = "1.0.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "ee2626afccd7561a06cf1367e2950c4718ea04565e20fb5029b6c7d8ad09abcf"
 
+[[package]]
+name = "easy-parallel"
+version = "3.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6907e25393cdcc1f4f3f513d9aac1e840eb1cc341a0fccb01171f7d14d10b946"
+
 [[package]]
 name = "eframe"
 version = "0.16.0"
@@ -793,7 +980,7 @@ dependencies = [
 name = "egui"
 version = "0.16.1"
 dependencies = [
- "ahash",
+ "ahash 0.7.6",
  "epaint",
  "nohash-hasher",
  "ron",
@@ -806,6 +993,7 @@ name = "egui-winit"
 version = "0.16.0"
 dependencies = [
  "copypasta",
+ "dark-light",
  "egui",
  "epi",
  "instant",
@@ -846,7 +1034,7 @@ dependencies = [
 name = "egui_glium"
 version = "0.16.0"
 dependencies = [
- "ahash",
+ "ahash 0.7.6",
  "bytemuck",
  "egui",
  "egui-winit",
@@ -941,6 +1129,27 @@ dependencies = [
  "syn",
 ]
 
+[[package]]
+name = "enumflags2"
+version = "0.7.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a25c90b056b3f84111cf183cbeddef0d3a0bbe9a674f057e1a1533c315f24def"
+dependencies = [
+ "enumflags2_derive",
+ "serde",
+]
+
+[[package]]
+name = "enumflags2_derive"
+version = "0.7.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "144ec79496cbab6f84fa125dc67be9264aef22eb8a28da8454d9c33f15108da4"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
 [[package]]
 name = "env_logger"
 version = "0.9.0"
@@ -959,7 +1168,7 @@ name = "epaint"
 version = "0.16.0"
 dependencies = [
  "ab_glyph",
- "ahash",
+ "ahash 0.7.6",
  "atomic_refcell",
  "bytemuck",
  "cint",
@@ -981,6 +1190,12 @@ dependencies = [
  "tracing",
 ]
 
+[[package]]
+name = "event-listener"
+version = "2.5.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "77f3309417938f28bf8228fcff79a4a37103981e3e186d2ccd19c74b38f4eb71"
+
 [[package]]
 name = "fancy-regex"
 version = "0.7.1"
@@ -991,6 +1206,15 @@ dependencies = [
  "regex",
 ]
 
+[[package]]
+name = "fastrand"
+version = "1.7.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c3fcf0cee53519c866c09b5de1f6c56ff9d647101f81c1964fa632e148896cdf"
+dependencies = [
+ "instant",
+]
+
 [[package]]
 name = "flate2"
 version = "1.0.22"
@@ -1034,6 +1258,59 @@ dependencies = [
  "percent-encoding",
 ]
 
+[[package]]
+name = "futures-core"
+version = "0.3.19"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d0c8ff0461b82559810cdccfde3215c3f373807f5e5232b71479bff7bb2583d7"
+
+[[package]]
+name = "futures-io"
+version = "0.3.19"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b1f9d34af5a1aac6fb380f735fe510746c38067c5bf16c7fd250280503c971b2"
+
+[[package]]
+name = "futures-lite"
+version = "1.12.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7694489acd39452c77daa48516b894c153f192c3578d5a839b62c58099fcbf48"
+dependencies = [
+ "fastrand",
+ "futures-core",
+ "futures-io",
+ "memchr",
+ "parking",
+ "pin-project-lite",
+ "waker-fn",
+]
+
+[[package]]
+name = "futures-sink"
+version = "0.3.19"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e3055baccb68d74ff6480350f8d6eb8fcfa3aa11bdc1a1ae3afdd0514617d508"
+
+[[package]]
+name = "futures-task"
+version = "0.3.19"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6ee7c6485c30167ce4dfb83ac568a849fe53274c831081476ee13e0dce1aad72"
+
+[[package]]
+name = "futures-util"
+version = "0.3.19"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d9b5cf40b47a271f77a8b1bec03ca09044d99d2372c0de244e66430761127164"
+dependencies = [
+ "futures-core",
+ "futures-sink",
+ "futures-task",
+ "pin-project-lite",
+ "pin-utils",
+ "slab",
+]
+
 [[package]]
 name = "gcc"
 version = "0.3.55"
@@ -1262,6 +1539,15 @@ version = "1.8.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "eabb4a44450da02c90444cf74558da904edde8fb4e9035a9a6a4e15445af0bd7"
 
+[[package]]
+name = "hashbrown"
+version = "0.9.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d7afe4a420e3fe79967a00898cc1f4db7c8a49a9333a29f8a4bd76a253d5cd04"
+dependencies = [
+ "ahash 0.4.7",
+]
+
 [[package]]
 name = "hashbrown"
 version = "0.11.2"
@@ -1286,6 +1572,12 @@ dependencies = [
  "libc",
 ]
 
+[[package]]
+name = "hex"
+version = "0.4.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7f24254aa9a54b5c858eaee2f5bccdb46aaf0e486a595ed5fd8f86ba55232a70"
+
 [[package]]
 name = "humantime"
 version = "2.1.0"
@@ -1332,7 +1624,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "282a6247722caba404c065016bbfa522806e51714c34f5dfc3e4a3a46fcb4223"
 dependencies = [
  "autocfg",
- "hashbrown",
+ "hashbrown 0.11.2",
 ]
 
 [[package]]
@@ -1429,9 +1721,9 @@ checksum = "830d08ce1d1d941e6b30645f1a0eb5643013d835ce3779a5fc208261dbe10f55"
 
 [[package]]
 name = "libc"
-version = "0.2.112"
+version = "0.2.116"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "1b03d17f364a3a042d5e5d46b053bbbf82c92c9430c592dd4c064dc6ee997125"
+checksum = "565dbd88872dbe4cc8a46e527f26483c1d1f7afa6b884a3bd6cd893d4f98da74"
 
 [[package]]
 name = "libloading"
@@ -1627,6 +1919,19 @@ dependencies = [
  "memoffset",
 ]
 
+[[package]]
+name = "nix"
+version = "0.23.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9f866317acbd3a240710c63f065ffb1e4fd466259045ccb504130b7f668f35c6"
+dependencies = [
+ "bitflags",
+ "cc",
+ "cfg-if 1.0.0",
+ "libc",
+ "memoffset",
+]
+
 [[package]]
 name = "nohash-hasher"
 version = "0.2.0"
@@ -1785,6 +2090,26 @@ version = "11.1.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "0ab1bc2a289d34bd04a330323ac98a1b4bc82c9d9fcb1e66b63caa84da26b575"
 
+[[package]]
+name = "ordered-multimap"
+version = "0.3.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1c672c7ad9ec066e428c00eb917124a06f08db19e2584de982cc34b1f4c12485"
+dependencies = [
+ "dlv-list",
+ "hashbrown 0.9.1",
+]
+
+[[package]]
+name = "ordered-stream"
+version = "0.0.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "44630c059eacfd6e08bdaa51b1db2ce33119caa4ddc1235e923109aa5f25ccb1"
+dependencies = [
+ "futures-core",
+ "pin-project-lite",
+]
+
 [[package]]
 name = "osmesa-sys"
 version = "0.1.2"
@@ -1815,6 +2140,12 @@ dependencies = [
  "system-deps",
 ]
 
+[[package]]
+name = "parking"
+version = "2.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "427c3892f9e783d91cc128285287e70a59e206ca452770ece88a76f7a3eddd72"
+
 [[package]]
 name = "parking_lot"
 version = "0.11.2"
@@ -1858,6 +2189,12 @@ version = "0.2.8"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "e280fbe77cc62c91527259e9442153f4688736748d24660126286329742b4c6c"
 
+[[package]]
+name = "pin-utils"
+version = "0.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8b870d8c151b6f2fb93e84a13146138f05d02ed11c7e7c54f8826aaaf7c9f184"
+
 [[package]]
 name = "pkg-config"
 version = "0.3.24"
@@ -1927,6 +2264,25 @@ dependencies = [
  "static_assertions",
 ]
 
+[[package]]
+name = "polling"
+version = "2.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "685404d509889fade3e86fe3a5803bca2ec09b0c0778d5ada6ec8bf7a8de5259"
+dependencies = [
+ "cfg-if 1.0.0",
+ "libc",
+ "log",
+ "wepoll-ffi",
+ "winapi",
+]
+
+[[package]]
+name = "ppv-lite86"
+version = "0.2.16"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "eb9f9e6e233e5c4a35559a617bf40a4ec447db2e84c20b55a6f83167b7e57872"
+
 [[package]]
 name = "proc-macro-crate"
 version = "1.1.0"
@@ -1964,6 +2320,46 @@ dependencies = [
  "proc-macro2",
 ]
 
+[[package]]
+name = "rand"
+version = "0.8.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2e7573632e6454cf6b99d7aac4ccca54be06da05aca2ef7423d22d27d4d4bcd8"
+dependencies = [
+ "libc",
+ "rand_chacha",
+ "rand_core",
+ "rand_hc",
+]
+
+[[package]]
+name = "rand_chacha"
+version = "0.3.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e6c10a63a0fa32252be49d21e7709d4d4baf8d231c2dbce1eaa8141b9b127d88"
+dependencies = [
+ "ppv-lite86",
+ "rand_core",
+]
+
+[[package]]
+name = "rand_core"
+version = "0.6.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d34f1408f55294453790c48b2f1ebbb1c5b4b7563eb1f418bcfcfdbb06ebb4e7"
+dependencies = [
+ "getrandom",
+]
+
+[[package]]
+name = "rand_hc"
+version = "0.3.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d51e9f596de227fda2ea6c84607f5558e196eeaf43c986b724ba4fb8fdf497e7"
+dependencies = [
+ "rand_core",
+]
+
 [[package]]
 name = "raw-window-handle"
 version = "0.4.2"
@@ -2089,6 +2485,16 @@ dependencies = [
  "serde",
 ]
 
+[[package]]
+name = "rust-ini"
+version = "0.17.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "63471c4aa97a1cf8332a5f97709a79a4234698de6a1f5087faf66f2dae810e22"
+dependencies = [
+ "cfg-if 1.0.0",
+ "ordered-multimap",
+]
+
 [[package]]
 name = "rustc-demangle"
 version = "0.1.21"
@@ -2212,6 +2618,32 @@ dependencies = [
  "serde",
 ]
 
+[[package]]
+name = "serde_repr"
+version = "0.1.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "98d0516900518c29efa217c298fa1f4e6c6ffc85ae29fd7f4ee48f176e1a9ed5"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
+[[package]]
+name = "sha1"
+version = "0.6.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c1da05c97445caa12d05e848c4a4fcbbea29e748ac28f7e80e9b010392063770"
+dependencies = [
+ "sha1_smol",
+]
+
+[[package]]
+name = "sha1_smol"
+version = "1.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ae1a47186c03a32177042e55dbc5fd5aee900b8e0069a8d70fba96a9375cd012"
+
 [[package]]
 name = "sharded-slab"
 version = "0.1.4"
@@ -2237,6 +2669,12 @@ version = "1.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "43b2853a4d09f215c24cc5489c992ce46052d359b5109343cbafbf26bc62f8a3"
 
+[[package]]
+name = "slab"
+version = "0.4.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9def91fd1e018fe007022791f865d0ccc9b3a0d5001e01aabb8b40e46000afb5"
+
 [[package]]
 name = "slotmap"
 version = "1.0.6"
@@ -2264,7 +2702,7 @@ dependencies = [
  "lazy_static",
  "log",
  "memmap2",
- "nix",
+ "nix 0.22.0",
  "pkg-config",
  "wayland-client",
  "wayland-cursor",
@@ -2281,6 +2719,16 @@ dependencies = [
  "wayland-client",
 ]
 
+[[package]]
+name = "socket2"
+version = "0.4.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "66d72b759436ae32898a2af0a14218dbf55efde3feeb170eb623637db85ee1e0"
+dependencies = [
+ "libc",
+ "winapi",
+]
+
 [[package]]
 name = "speech-dispatcher"
 version = "0.9.0"
@@ -2688,6 +3136,12 @@ version = "0.9.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "49874b5167b65d7193b8aba1567f5c7d93d001cafc34600cee003eda787e483f"
 
+[[package]]
+name = "waker-fn"
+version = "1.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9d5b2c62b4012a3e1eca5a7e077d13b3bf498c4073e33ccd58626607748ceeca"
+
 [[package]]
 name = "walkdir"
 version = "2.3.2"
@@ -2780,7 +3234,7 @@ dependencies = [
  "bitflags",
  "downcast-rs",
  "libc",
- "nix",
+ "nix 0.22.0",
  "scoped-tls",
  "wayland-commons",
  "wayland-scanner",
@@ -2793,7 +3247,7 @@ version = "0.29.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "94f6e5e340d7c13490eca867898c4cec5af56c27a5ffe5c80c6fc4708e22d33e"
 dependencies = [
- "nix",
+ "nix 0.22.0",
  "once_cell",
  "smallvec",
  "wayland-sys",
@@ -2805,7 +3259,7 @@ version = "0.29.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "c52758f13d5e7861fc83d942d3d99bf270c83269575e52ac29e5b73cb956a6bd"
 dependencies = [
- "nix",
+ "nix 0.22.0",
  "wayland-client",
  "xcursor",
 ]
@@ -2894,6 +3348,15 @@ dependencies = [
  "webpki",
 ]
 
+[[package]]
+name = "wepoll-ffi"
+version = "0.1.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d743fdedc5c64377b5fc2bc036b01c7fd642205a0d96356034ae3404d49eb7fb"
+dependencies = [
+ "cc",
+]
+
 [[package]]
 name = "which"
 version = "4.2.2"
@@ -3018,6 +3481,15 @@ dependencies = [
  "x11-dl",
 ]
 
+[[package]]
+name = "winreg"
+version = "0.8.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d107f8c6e916235c4c01cabb3e8acf7bea8ef6a63ca2e7fa0527c049badfc48c"
+dependencies = [
+ "winapi",
+]
+
 [[package]]
 name = "x11-clipboard"
 version = "0.5.3"
@@ -3072,3 +3544,90 @@ checksum = "56c1936c4cc7a1c9ab21a1ebb602eb942ba868cbd44a99cb7cdc5892335e1c85"
 dependencies = [
  "linked-hash-map",
 ]
+
+[[package]]
+name = "zbus"
+version = "2.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "22128509baa98972e4a756a32fff9bd55fd6e4d1426c70ce0ef860d3788f9938"
+dependencies = [
+ "async-broadcast",
+ "async-channel",
+ "async-executor",
+ "async-io",
+ "async-lock",
+ "async-recursion",
+ "async-task",
+ "async-trait",
+ "byteorder",
+ "derivative",
+ "enumflags2",
+ "event-listener",
+ "futures-core",
+ "futures-sink",
+ "futures-util",
+ "hex",
+ "lazy_static",
+ "nix 0.23.1",
+ "once_cell",
+ "ordered-stream",
+ "rand",
+ "serde",
+ "serde_repr",
+ "sha1",
+ "static_assertions",
+ "winapi",
+ "zbus_macros",
+ "zbus_names",
+ "zvariant",
+]
+
+[[package]]
+name = "zbus_macros"
+version = "2.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "fc6f42176fbc4f106e28cfa283c4d97b067c3a194a1d8fe335e0080945c88eb0"
+dependencies = [
+ "proc-macro-crate",
+ "proc-macro2",
+ "quote",
+ "regex",
+ "syn",
+]
+
+[[package]]
+name = "zbus_names"
+version = "2.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "45dfcdcf87b71dad505d30cc27b1b7b88a64b6d1c435648f48f9dbc1fdc4b7e1"
+dependencies = [
+ "serde",
+ "static_assertions",
+ "zvariant",
+]
+
+[[package]]
+name = "zvariant"
+version = "3.1.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "49ea5dc38b2058fae6a5b79009388143dadce1e91c26a67f984a0fc0381c8033"
+dependencies = [
+ "byteorder",
+ "enumflags2",
+ "libc",
+ "serde",
+ "static_assertions",
+ "zvariant_derive",
+]
+
+[[package]]
+name = "zvariant_derive"
+version = "3.1.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8c2cecc5a61c2a053f7f653a24cd15b3b0195d7f7ddb5042c837fb32e161fb7a"
+dependencies = [
+ "proc-macro-crate",
+ "proc-macro2",
+ "quote",
+ "syn",
+]
diff --git a/eframe/CHANGELOG.md b/eframe/CHANGELOG.md
index 42e78cca..ebe4c607 100644
--- a/eframe/CHANGELOG.md
+++ b/eframe/CHANGELOG.md
@@ -8,6 +8,7 @@ NOTE: [`egui_web`](../egui_web/CHANGELOG.md), [`egui-winit`](../egui-winit/CHANG
 * Removed `Frame::alloc_texture`. Use `egui::Context::load_texture` instead ([#1110](https://github.com/emilk/egui/pull/1110)).
 * The default native backend is now `egui_glow` (instead of `egui_glium`) ([#1020](https://github.com/emilk/egui/pull/1020)).
 * The default web painter is now `egui_glow` (instead of WebGL) ([#1020](https://github.com/emilk/egui/pull/1020)).
+* Automatically detect and apply dark or light mode from system ([#1045](https://github.com/emilk/egui/pull/1045)).
 * Fix horizontal scrolling direction on Linux.
 * Added `App::on_exit_event` ([#1038](https://github.com/emilk/egui/pull/1038))
 * Shift-scroll will now result in horizontal scrolling on all platforms ([#1136](https://github.com/emilk/egui/pull/1136)).
diff --git a/egui-winit/CHANGELOG.md b/egui-winit/CHANGELOG.md
index 426fbc6a..80de1eaa 100644
--- a/egui-winit/CHANGELOG.md
+++ b/egui-winit/CHANGELOG.md
@@ -5,6 +5,7 @@ All notable changes to the `egui-winit` integration will be noted in this file.
 
 ## Unreleased
 * Fixed horizontal scrolling direction on Linux.
+* Automatically detect and apply dark or light mode from system ([#1045](https://github.com/emilk/egui/pull/1045)).
 * Replaced `std::time::Instant` with `instant::Instant` for WebAssembly compatability ([#1023](https://github.com/emilk/egui/pull/1023))
 * Shift-scroll will now result in horizontal scrolling on all platforms ([#1136](https://github.com/emilk/egui/pull/1136)).
 * Require knowledge about max texture side (e.g. `GL_MAX_TEXTURE_SIZE`)) ([#1154](https://github.com/emilk/egui/pull/1154)).
diff --git a/egui-winit/Cargo.toml b/egui-winit/Cargo.toml
index 8e6c8882..fe5715ea 100644
--- a/egui-winit/Cargo.toml
+++ b/egui-winit/Cargo.toml
@@ -30,6 +30,7 @@ winit = "0.26.1"
 epi = { version = "0.16.0", path = "../epi", optional = true }
 
 copypasta = { version = "0.7", optional = true }
+dark-light = { version = "0.2.1", optional = true } # detect dark mode system preference
 serde = { version = "1.0", optional = true, features = ["derive"] }
 webbrowser = { version = "0.5", optional = true }
 
@@ -37,7 +38,7 @@ webbrowser = { version = "0.5", optional = true }
 tts = { version = "0.19", optional = true }
 
 [features]
-default = ["clipboard", "links"]
+default = ["clipboard", "dark-light", "links"]
 
 # enable cut/copy/paste to OS clipboard.
 # if disabled a clipboard will be simulated so you can still copy/paste within the egui app.
diff --git a/egui-winit/src/epi.rs b/egui-winit/src/epi.rs
index 995d8f8b..b4762be5 100644
--- a/egui-winit/src/epi.rs
+++ b/egui-winit/src/epi.rs
@@ -223,11 +223,13 @@ impl EpiIntegration {
 
         *egui_ctx.memory() = persistence.load_memory().unwrap_or_default();
 
+        let prefer_dark_mode = prefer_dark_mode();
+
         let frame = epi::Frame::new(epi::backend::FrameData {
             info: epi::IntegrationInfo {
                 name: integration_name,
                 web_info: None,
-                prefer_dark_mode: None, // TODO: figure out system default
+                prefer_dark_mode,
                 cpu_usage: None,
                 native_pixels_per_point: Some(crate::native_pixels_per_point(window)),
             },
@@ -235,6 +237,12 @@ impl EpiIntegration {
             repaint_signal,
         });
 
+        if prefer_dark_mode == Some(true) {
+            egui_ctx.set_visuals(egui::Visuals::dark());
+        } else {
+            egui_ctx.set_visuals(egui::Visuals::light());
+        }
+
         let mut slf = Self {
             frame,
             persistence,
@@ -340,3 +348,16 @@ impl EpiIntegration {
             .save(&mut *self.app, &self.egui_ctx, window);
     }
 }
+
+#[cfg(feature = "dark-light")]
+fn prefer_dark_mode() -> Option<bool> {
+    match dark_light::detect() {
+        dark_light::Mode::Dark => Some(true),
+        dark_light::Mode::Light => Some(false),
+    }
+}
+
+#[cfg(not(feature = "dark-light"))]
+fn prefer_dark_mode() -> Option<bool> {
+    None
+}
diff --git a/egui_glium/CHANGELOG.md b/egui_glium/CHANGELOG.md
index 45cb1139..3de396f5 100644
--- a/egui_glium/CHANGELOG.md
+++ b/egui_glium/CHANGELOG.md
@@ -5,6 +5,7 @@ All notable changes to the `egui_glium` integration will be noted in this file.
 ## Unreleased
 * `EguiGlium::run` no longer returns the shapes to paint, but stores them internally until you call `EguiGlium::paint` ([#1110](https://github.com/emilk/egui/pull/1110)).
 * Optimize the painter and texture uploading ([#1110](https://github.com/emilk/egui/pull/1110)).
+* Automatically detect and apply dark or light mode from system ([#1045](https://github.com/emilk/egui/pull/1045)).
 
 
 ## 0.16.0 - 2021-12-29
diff --git a/egui_glow/CHANGELOG.md b/egui_glow/CHANGELOG.md
index a5eaa4b2..b5bcdb6d 100644
--- a/egui_glow/CHANGELOG.md
+++ b/egui_glow/CHANGELOG.md
@@ -7,7 +7,9 @@ All notable changes to the `egui_glow` integration will be noted in this file.
 * Added `set_texture_filter` method to `Painter` ([#1041](https://github.com/emilk/egui/pull/1041)).
 * Fix failure to run in Chrome ([#1092](https://github.com/emilk/egui/pull/1092)).
 * `EguiGlow::new` now takes `&winit::Window` because there are no reason to use `&glutin::WindowedContext` ([#1151](https://github.com/emilk/egui/pull/1151)).
-* `EguiGlow::paint` now takes `&winit::Window` because there are no reason to use `&glutin::WindowedContext` ([#1151](https://github.com/emilk/egui/pull/1151)).  
+* `EguiGlow::paint` now takes `&winit::Window` because there are no reason to use `&glutin::WindowedContext` ([#1151](https://github.com/emilk/egui/pull/1151)).
+* Automatically detect and apply dark or light mode from system ([#1045](https://github.com/emilk/egui/pull/1045)).
+
 
 ## 0.16.0 - 2021-12-29
 * Made winit/glutin an optional dependency ([#868](https://github.com/emilk/egui/pull/868)).
diff --git a/egui_glow/Cargo.toml b/egui_glow/Cargo.toml
index 9b307f1c..cd0add6e 100644
--- a/egui_glow/Cargo.toml
+++ b/egui_glow/Cargo.toml
@@ -35,7 +35,7 @@ memoffset = "0.6"
 tracing = "0.1"
 
 [target.'cfg(not(target_arch = "wasm32"))'.dependencies]
-egui-winit = { version = "0.16.0", path = "../egui-winit", default-features = false, features = ["epi"], optional = true }
+egui-winit = { version = "0.16.0", path = "../egui-winit", default-features = false, features = ["dark-light", "epi"], optional = true }
 glutin = { version = "0.28.0", optional = true }
 
 [target.'cfg(target_arch = "wasm32")'.dependencies]