From 8f74c3790e814678942c990c16f98c8bf16fdc59 Mon Sep 17 00:00:00 2001
From: MarekSpodBiedry <73122968+MarekSpodBiedry@users.noreply.github.com>
Date: Sat, 17 Oct 2026 07:45:24 +0200
Subject: [PATCH] Replace non-ASCII characters in EXR layer names so ProEXR
 export no longer panics (#1702)

---
 crates/engine/src/commands/frame_export.rs |  5 +++--
 crates/engine/src/tests_frame_export.rs    | 13 +++++++++++++
 2 files changed, 16 insertions(+), 2 deletions(-)

diff --git a/crates/engine/src/commands/frame_export.rs b/crates/engine/src/commands/frame_export.rs
index c939d67e..baad9b6e 100644
--- a/crates/engine/src/commands/frame_export.rs
+++ b/crates/engine/src/commands/frame_export.rs
@@ -140,9 +140,10 @@ fn srgb_to_linear(c: f32) -> f32 {
     if c <= 0.04045 { c / 12.92 } else { ((c + 0.055) / 1.055).powf(2.4) }
 }
 
-/// A unique EXR layer name (no dots: they separate the layer from the channel).
+/// A unique EXR layer name (no dots: they separate the layer from the channel). Printable ASCII only:
+/// the `exr` crate panics on characters it cannot store in a channel name (#1702).
 fn exr_name(name: &str, used: &mut Vec<String>) -> String {
-    let base: String = name.chars().map(|c| if c == '.' || c.is_control() { '_' } else { c }).collect();
+    let base: String = name.chars().map(|c| if c == '.' || !(c == ' ' || c.is_ascii_graphic()) { '_' } else { c }).collect();
     let base = if base.trim().is_empty() { "Layer".to_string() } else { base };
     let mut n = base.clone();
     let mut k = 2;
diff --git a/crates/engine/src/tests_frame_export.rs b/crates/engine/src/tests_frame_export.rs
index 87b0864a..a45c5d44 100644
--- a/crates/engine/src/tests_frame_export.rs
+++ b/crates/engine/src/tests_frame_export.rs
@@ -77,6 +77,19 @@ fn proexr_writes_layer_prefixed_channels_and_the_composite() {
     assert!(at("R", 16, 16) < 0.5, "multiplied by 50% blue (linear)");
 }
 
+#[test]
+fn proexr_names_a_non_ascii_layer_with_underscores_instead_of_panicking() {
+    let mut s = Session::default();
+    s.execute("comp.new", json!({"name": "Frame", "width": 8, "height": 8, "frameRate": 24, "duration": 1})).unwrap();
+    s.execute("layer.newSolid", json!({"name": "你好", "color": "#ff0000"})).unwrap();
+    let dir = out_dir("frame-exr-non-ascii");
+    let path = dir.join("frame.exr").to_string_lossy().to_string();
+    let r = s.execute("comp.saveFrameAsExr", json!({"path": path})).unwrap();
+    let names: Vec<&str> = r["channels"].as_array().unwrap().iter().map(|c| c.as_str().unwrap()).collect();
+    assert!(names.contains(&"__.R") && names.contains(&"__.A"), "{names:?}");
+    assert!(std::path::Path::new(&path).exists());
+}
+
 /// Save a 32×32 comp holding one opaque solid of `color` (an sRGB-encoded triple) as ProEXR and
 /// return the centre pixel of the composite and of the solid's own layer: `[R, G, B]` each.
 fn proexr_centre(color: [f64; 3], bit_depth: u64) -> ([f32; 3], [f32; 3]) {