S2.66: Settings suggests the SAM 2 size that suits this computer

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

crates/engine/src/analysis/models.rs

@@ -420,7 +420,13 @@ fn list(s: &mut Session, task: Task) -> Result<Value> {
         "active": st.active.is_none(),
     })];
     for m in seg::models(task) {
+        #[cfg(not(target_arch = "wasm32"))]
+        let (recommended, hint) = (effectcraft_sam2::mask::recommended().id == m.id, effectcraft_sam2::mask::hint(m.id));
+        #[cfg(target_arch = "wasm32")]
+        let (recommended, hint) = (false, None::<String>);
         v.push(json!({
+            "recommended": recommended,
+            "hint": hint,
             "id": m.id,
             "name": m.name,
             "description": m.description,

crates/sam2/src/mask.rs

@@ -148,6 +148,27 @@ pub fn load(bytes: &[u8]) -> std::result::Result<Arc<Sam2Mask>, String> {
     Ok(Arc::new(Sam2Mask::with_info(Arc::new(model), info)))
 }
 
+/// The size to suggest on this computer: Small when a GPU is usable (no slower to run than Tiny there, and more accurate),
+/// Tiny otherwise (the bigger backbones take several seconds a frame on a CPU).
+pub fn recommended() -> &'static ModelInfo {
+    if crate::gpu::Gpu::shared().is_ok() { &effectcraft_segment::SAM2_SMALL } else { &SAM2_TINY }
+}
+
+/// A one-line note for the Settings list: what suits this computer, and what the bigger sizes cost without a GPU.
+pub fn hint(id: &str) -> Option<String> {
+    if !SIZES.iter().any(|m| m.id == id) {
+        return None;
+    }
+    let gpu = crate::gpu::Gpu::shared().is_ok();
+    Some(match (id == recommended().id, gpu, id) {
+        (true, true, _) => "Recommended: a GPU was found, and this size is no slower than Tiny on it.".to_string(),
+        (true, false, _) => "Recommended: no GPU was found, and this is the quickest on a CPU.".to_string(),
+        (false, false, "sam2.1-hiera-base-plus" | "sam2.1-hiera-large") => "Slow without a GPU (several seconds a frame); none was found.".to_string(),
+        (false, true, "sam2.1-hiera-large") => "For difficult footage; about 0.7 s of GPU time to look at each frame.".to_string(),
+        _ => return None,
+    })
+}
+
 /// The registry entries this crate loads.
 pub const SIZES: [&ModelInfo; 4] = [&SAM2_TINY, &effectcraft_segment::SAM2_SMALL, &effectcraft_segment::SAM2_BASE_PLUS, &effectcraft_segment::SAM2_LARGE];
 

crates/ui-egui/src/panels/settings.rs

@@ -489,6 +489,9 @@ fn models_ui(app: &mut EffectcraftApp, ui: &mut egui::Ui, t: &Tokens, acts: &mut
                 ui.label(RichText::new(state).color(if active { t.accent } else { t.text_dim }));
             });
             ui.label(RichText::new(m["description"].as_str().unwrap_or_default()).color(t.text_dim));
+            if let Some(hint) = m["hint"].as_str() {
+                ui.label(RichText::new(hint).color(if m["recommended"].as_bool().unwrap_or(false) { t.accent } else { t.text_dim }));
+            }
             if let Some(by) = m["authors"].as_str() {
                 ui.label(RichText::new(format!("By {by}")).color(t.text_dim));
             }