Merge: master at 0.13.6, with the drag-ghost file and the shared model lookup ported into the split modules

ui/dr-ui/src/collections_ui/drag.rs

@@ -86,6 +86,107 @@ pub(super) fn compose_drag_image(thumbs: &[slint::Image]) -> slint::Image {
     slint::Image::from_rgba8_premultiplied(canvas)
 }
 
+/// Hand the composite to the renderer by way of a file.
+///
+/// **A workaround for a renderer fault, and it should read as one.** The
+/// ghost under the cursor is drawn by Slint's own drag overlay, which
+/// uploads the image as a texture, draws it, and drops the texture in the
+/// same call. With the wgpu FemtoVG renderer that drop is immediate and
+/// the draw is deferred to the frame's flush, so by the time the frame is
+/// rendered the texture is gone and the renderer binds its placeholder
+/// instead — a solid red rectangle the size of the ghost. An image with a
+/// cache key is kept in the renderer's texture cache until after the
+/// flush; an image built from pixels has none, and only a path gives one.
+/// So the composite goes to disk as a PNG and comes back through
+/// `load_from_path`. Slint 1.17.1, `draw_image_direct` in the FemtoVG
+/// item renderer; the GL FemtoVG renderer is not affected.
+///
+/// One file per drag, named uniquely: the core caches decoded images by
+/// path, so reusing a name would show the previous drag's ghost. The file
+/// is removed when the drag ends, or when the next one begins.
+///
+/// If anything on the way fails the composite is handed over as it is,
+/// which on the affected renderer draws the placeholder — no worse than
+/// before, and a log line says why.
+pub(super) fn drag_image_via_file(composite: slint::Image) -> slint::Image {
+    let Some(buffer) = composite.to_rgba8() else {
+        log::warn!("drag ghost: the composite has no pixels to write");
+        return composite;
+    };
+    log::debug!("drag ghost: {}×{}", buffer.width(), buffer.height());
+    if buffer.width() == 0 || buffer.height() == 0 {
+        return composite;
+    }
+    match write_drag_image(&buffer) {
+        Ok(path) => match slint::Image::load_from_path(&path) {
+            Ok(image) => {
+                forget_drag_image_file();
+                *DRAG_IMAGE_FILE.lock().unwrap() = Some(path);
+                image
+            }
+            Err(_) => {
+                log::warn!("drag ghost: {} did not load back", path.display());
+                let _ = std::fs::remove_file(&path);
+                composite
+            }
+        },
+        Err(e) => {
+            log::warn!("drag ghost: {e}");
+            composite
+        }
+    }
+}
+
+/// The file the current drag's ghost is loaded from, if any.
+static DRAG_IMAGE_FILE: std::sync::Mutex<Option<std::path::PathBuf>> = std::sync::Mutex::new(None);
+
+fn write_drag_image(
+    buffer: &slint::SharedPixelBuffer<slint::Rgba8Pixel>,
+) -> std::io::Result<std::path::PathBuf> {
+    use std::sync::atomic::{AtomicU64, Ordering};
+    static SERIAL: AtomicU64 = AtomicU64::new(0);
+
+    let dir = crate::library::scratch_dir();
+    std::fs::create_dir_all(&dir)?;
+    let path = dir.join(format!(
+        "drag-{}-{}.png",
+        std::process::id(),
+        SERIAL.fetch_add(1, Ordering::Relaxed)
+    ));
+    let file = std::fs::File::create(&path)?;
+    let mut encoder = png::Encoder::new(
+        std::io::BufWriter::new(file),
+        buffer.width(),
+        buffer.height(),
+    );
+    encoder.set_color(png::ColorType::Rgba);
+    encoder.set_depth(png::BitDepth::Eight);
+    // Fastest: this is a 160px bitmap written once per drag and read once.
+    encoder.set_compression(png::Compression::Fastest);
+    let mut writer = encoder.write_header().map_err(std::io::Error::other)?;
+    writer
+        .write_image_data(buffer.as_bytes())
+        .map_err(std::io::Error::other)?;
+    writer.finish().map_err(std::io::Error::other)?;
+    Ok(path)
+}
+
+pub(super) fn forget_drag_image_file() {
+    if let Some(path) = DRAG_IMAGE_FILE.lock().unwrap().take() {
+        let _ = std::fs::remove_file(path);
+    }
+}
+
+/// Draw one thumbnail into the composite, scaled to `tw`×`th` at `dx`,`dy`.
+///
+/// Nearest-neighbour: this is a transient 160px cursor bitmap, and a filtered
+/// resample would cost more than it could visibly buy. `dim` darkens the layers
+/// beneath the top one so the stack reads as depth rather than as a smear.
+///
+/// The buffer is premultiplied, so the alpha applied here is baked into the
+/// colour channels as well.
+#[allow(clippy::too_many_arguments)]
+
 /// Draw one thumbnail into the composite, scaled to `tw`×`th` at `dx`,`dy`.
 ///
 /// Nearest-neighbour: this is a transient 160px cursor bitmap, and a filtered

ui/dr-ui/src/collections_ui/wiring_grid.rs

@@ -19,7 +19,10 @@ use crate::library;
 use crate::{AppWindow, Collections};
 
 use super::controller::{decide_drop, CollectionsController, Drop};
-use super::drag::{arm_hold, arm_spring, collapse_spring_opened, compose_drag_image};
+use super::drag::{
+    arm_hold, arm_spring, collapse_spring_opened, compose_drag_image, drag_image_via_file,
+    forget_drag_image_file,
+};
 use super::press::select_row;
 use super::rename_menu::unique_name;
 use super::trash::{drain_trash, start_restore, start_trash};
@@ -603,7 +606,7 @@ fn wire_drag(
                     .map(|c| c.thumbnail)
                     .collect()
             };
-            w.set_library_drag_image(compose_drag_image(&thumbs));
+            w.set_library_drag_image(drag_image_via_file(compose_drag_image(&thumbs)));
 
             *ctl.dragging.borrow_mut() = carried.clone();
             sync_selection(&w, &ctl, &ids);
@@ -763,6 +766,7 @@ fn wire_drag(
             // released — it holds a copy of every thumbnail it composited.
             sync_lifted(&w, &[], &visible());
             w.set_library_drag_image(slint::Image::default());
+            forget_drag_image_file();
 
             if landed.is_some() {
                 let borrow = catalog.borrow();

ui/dr-ui/src/inference.rs

@@ -19,23 +19,26 @@ use dr_types::FaceDetector;
 /// fingerprints the model files and a probe before they land would be a
 /// probe of nothing.
 pub fn init(runtime_dirs: Vec<PathBuf>) {
-    let dir = crate::library::shared_face_models_dir();
-    let mut models: Vec<(Role, PathBuf)> = FaceDetector::ALL
+    // Each file where the app will actually load it from — the user's
+    // shared directory, else the package's — so a fresh install with models
+    // only under `/usr/share` probes and compiles for them rather than
+    // finding nothing and settling on the CPU.
+    let mut wanted: Vec<(Role, &str)> = FaceDetector::ALL
         .iter()
-        .map(|d| (Role::Detector, dir.join(d.file_name())))
+        .map(|d| (Role::Detector, d.file_name()))
+        .collect();
+    wanted.extend([
+        (Role::Embedder, "arcface_mbf_b1.onnx"),
+        (Role::Scene, "yolo26s-sem-ade20k.onnx"),
+        (Role::Landmarks, crate::library::LANDMARK_MODEL),
+        (Role::EyeClassifier, crate::library::EYE_MODEL),
+        (Role::EyeClassifier, crate::library::SUNGLASSES_MODEL),
+        (Role::Inpainter, crate::library::INPAINT_MODEL),
+    ]);
+    let models: Vec<(Role, PathBuf)> = wanted
+        .into_iter()
+        .filter_map(|(role, name)| Some((role, crate::library::shared_model(name)?)))
         .collect();
-    models.push((Role::Embedder, dir.join("arcface_mbf_b1.onnx")));
-    models.push((Role::Scene, dir.join("yolo26s-sem-ade20k.onnx")));
-    models.push((Role::Landmarks, dir.join(crate::library::LANDMARK_MODEL)));
-    models.push((Role::EyeClassifier, dir.join(crate::library::EYE_MODEL)));
-    models.push((
-        Role::EyeClassifier,
-        dir.join(crate::library::SUNGLASSES_MODEL),
-    ));
-    if let Some(p) = crate::library::inpaint_model() {
-        models.push((Role::Inpainter, p));
-    }
-    models.retain(|(_, p)| p.is_file());
 
     dr_inference_engine::init(dr_inference_engine::Config {
         runtime_dirs,
@@ -75,12 +78,13 @@ pub fn user_runtime_dir() -> PathBuf {
 /// Which form the current backend loads `detector` in, given the files on
 /// this device — the fact `faces.model_id` has to carry (§7).
 ///
-/// Reads the shared directory only. An account-private model directory can
-/// override the file `library::face_models` loads, but not which form the
-/// backend wants, and the int8 sibling is something a packager ships, not
-/// something a user drops in.
+/// Reads the shared and system directories only. An account-private model
+/// directory can override the file `library::face_models` loads, but not
+/// which form the backend wants, and the int8 sibling is something a
+/// packager ships, not something a user drops in.
 pub fn detector_form(detector: FaceDetector) -> Form {
-    let canonical = crate::library::shared_face_models_dir().join(detector.file_name());
+    let canonical = crate::library::shared_model(detector.file_name())
+        .unwrap_or_else(|| crate::library::shared_face_models_dir().join(detector.file_name()));
     dr_inference_engine::resolve_model(Role::Detector, &canonical).1
 }
 

ui/dr-ui/src/library/paths.rs

@@ -227,6 +227,15 @@ pub fn inference_cache_dir() -> PathBuf {
     data_root().join("inference")
 }
 
+/// Somewhere to put a file that only needs to exist for a moment.
+///
+/// Under the data root rather than `std::env::temp_dir()`, which on Android
+/// names a directory the app cannot write to. Nothing here survives a
+/// launch on purpose: whoever writes into it deletes what they wrote.
+pub fn scratch_dir() -> PathBuf {
+    data_root().join("scratch")
+}
+
 /// The detector and embedder files, if both are present — and the eye
 /// models beside them, if those are.
 ///
@@ -341,6 +350,18 @@ pub(super) fn system_face_models_dirs() -> Vec<PathBuf> {
         .collect()
 }
 
+/// The file `name` in the shared user models directory, else in the first
+/// system directory that has it — the search every account-independent
+/// model lookup makes, and the one the inference engine is told about, so
+/// that a package's models under `/usr/share` are probed and compiled for
+/// exactly as a user's own would be.
+pub fn shared_model(name: &str) -> Option<PathBuf> {
+    std::iter::once(shared_face_models_dir())
+        .chain(system_face_models_dirs())
+        .map(|d| d.join(name))
+        .find(|p| p.is_file())
+}
+
 /// TRACES: FR-MRG-4
 /// The panorama border filler, as shipped in `models/inpaint/`.
 pub const INPAINT_MODEL: &str = "migan-512.onnx";
@@ -351,10 +372,7 @@ pub const INPAINT_MODEL: &str = "migan-512.onnx";
 /// the per-account step, because a fill is not identity-bearing and no
 /// library has a reason to pin its own.
 pub fn inpaint_model() -> Option<PathBuf> {
-    std::iter::once(shared_face_models_dir())
-        .chain(system_face_models_dirs())
-        .map(|d| d.join(INPAINT_MODEL))
-        .find(|p| p.is_file())
+    shared_model(INPAINT_MODEL)
 }
 
 #[cfg(test)]