Work on sampler nodes, fix slew limiter

daw-backend/src/audio/engine.rs

@@ -466,6 +466,66 @@ impl Engine {
         }
     }
 
+    /// Read audio from pool as mono f32 samples.
+    /// Handles all storage types: InMemory/Mapped use read_samples(),
+    /// Compressed falls back to decoding from the file path.
+    fn read_mono_from_pool(pool: &crate::audio::pool::AudioClipPool, pool_index: usize) -> Option<(Vec<f32>, f32)> {
+        let audio_file = pool.get_file(pool_index)?;
+        let channels = audio_file.channels as usize;
+        let frames = audio_file.frames as usize;
+        let sample_rate = audio_file.sample_rate as f32;
+
+        // Try read_samples first (works for InMemory and Mapped)
+        let mut mono_samples = vec![0.0f32; frames];
+        let read_count = if channels == 1 {
+            audio_file.read_samples(0, frames, 0, &mut mono_samples)
+        } else {
+            let mut channel_buf = vec![0.0f32; frames];
+            let mut count = 0;
+            for ch in 0..channels {
+                count = audio_file.read_samples(0, frames, ch, &mut channel_buf);
+                for (i, &s) in channel_buf.iter().enumerate() {
+                    mono_samples[i] += s;
+                }
+            }
+            let scale = 1.0 / channels as f32;
+            for s in &mut mono_samples {
+                *s *= scale;
+            }
+            count
+        };
+
+        if read_count > 0 {
+            return Some((mono_samples, sample_rate));
+        }
+
+        // Compressed storage: decode from file path using sample_loader
+        let path = audio_file.path.to_string_lossy();
+        if !path.starts_with("<embedded") {
+            if let Ok(sample_data) = crate::audio::sample_loader::load_audio_file(&*path) {
+                return Some((sample_data.samples, sample_data.sample_rate as f32));
+            }
+        }
+
+        // Last resort: try interleaved data() and mix down
+        let data = audio_file.data();
+        if !data.is_empty() && channels > 0 {
+            let actual_frames = data.len() / channels;
+            let mut mono = vec![0.0f32; actual_frames];
+            for frame in 0..actual_frames {
+                let mut sum = 0.0f32;
+                for ch in 0..channels {
+                    sum += data[frame * channels + ch];
+                }
+                mono[frame] = sum / channels as f32;
+            }
+            return Some((mono, sample_rate));
+        }
+
+        eprintln!("[read_mono_from_pool] Failed to read audio from pool_index={}", pool_index);
+        None
+    }
+
     /// Handle a command from the UI thread
     fn handle_command(&mut self, cmd: Command) {
         match cmd {
@@ -1586,6 +1646,38 @@ impl Engine {
                 }
             }
 
+            Command::SamplerLoadFromPool(track_id, node_id, pool_index) => {
+                use crate::audio::node_graph::nodes::SimpleSamplerNode;
+
+                let sample_result = Self::read_mono_from_pool(&self.audio_pool, pool_index);
+
+                if let Some((mono_samples, sample_rate)) = sample_result {
+                    if let Some(TrackNode::Midi(track)) = self.project.get_track_mut(track_id) {
+                        let graph = &mut track.instrument_graph;
+                        let node_idx = NodeIndex::new(node_id as usize);
+                        if let Some(graph_node) = graph.get_graph_node_mut(node_idx) {
+                            if let Some(sampler_node) = graph_node.node.as_any_mut().downcast_mut::<SimpleSamplerNode>() {
+                                sampler_node.set_sample(mono_samples, sample_rate);
+                            }
+                        }
+                    }
+                }
+            }
+
+            Command::SamplerSetRootNote(track_id, node_id, root_note) => {
+                use crate::audio::node_graph::nodes::SimpleSamplerNode;
+
+                if let Some(TrackNode::Midi(track)) = self.project.get_track_mut(track_id) {
+                    let graph = &mut track.instrument_graph;
+                    let node_idx = NodeIndex::new(node_id as usize);
+                    if let Some(graph_node) = graph.get_graph_node_mut(node_idx) {
+                        if let Some(sampler_node) = graph_node.node.as_any_mut().downcast_mut::<SimpleSamplerNode>() {
+                            sampler_node.set_root_note(root_note);
+                        }
+                    }
+                }
+            }
+
             Command::MultiSamplerAddLayer(track_id, node_id, file_path, key_min, key_max, root_key, velocity_min, velocity_max, loop_start, loop_end, loop_mode) => {
                 use crate::audio::node_graph::nodes::MultiSamplerNode;
 
@@ -1604,6 +1696,29 @@ impl Engine {
                 }
             }
 
+            Command::MultiSamplerAddLayerFromPool(track_id, node_id, pool_index, key_min, key_max, root_key) => {
+                use crate::audio::node_graph::nodes::MultiSamplerNode;
+                use crate::audio::node_graph::nodes::LoopMode;
+
+                let sample_result = Self::read_mono_from_pool(&self.audio_pool, pool_index);
+
+                if let Some((mono_samples, sample_rate)) = sample_result {
+                    if let Some(TrackNode::Midi(track)) = self.project.get_track_mut(track_id) {
+                        let graph = &mut track.instrument_graph;
+                        let node_idx = NodeIndex::new(node_id as usize);
+                        if let Some(graph_node) = graph.get_graph_node_mut(node_idx) {
+                            if let Some(multi_node) = graph_node.node.as_any_mut().downcast_mut::<MultiSamplerNode>() {
+                                multi_node.add_layer(
+                                    mono_samples, sample_rate,
+                                    key_min, key_max, root_key,
+                                    0, 127, None, None, LoopMode::OneShot,
+                                );
+                            }
+                        }
+                    }
+                }
+            }
+
             Command::MultiSamplerUpdateLayer(track_id, node_id, layer_index, key_min, key_max, root_key, velocity_min, velocity_max, loop_start, loop_end, loop_mode) => {
                 use crate::audio::node_graph::nodes::MultiSamplerNode;
 
@@ -3099,11 +3214,26 @@ impl EngineController {
         let _ = self.command_tx.push(Command::SamplerLoadSample(track_id, node_id, file_path));
     }
 
+    /// Load a sample from the audio pool into a SimpleSampler node
+    pub fn sampler_load_from_pool(&mut self, track_id: TrackId, node_id: u32, pool_index: usize) {
+        let _ = self.command_tx.push(Command::SamplerLoadFromPool(track_id, node_id, pool_index));
+    }
+
+    /// Set the root note for a SimpleSampler node
+    pub fn sampler_set_root_note(&mut self, track_id: TrackId, node_id: u32, root_note: u8) {
+        let _ = self.command_tx.push(Command::SamplerSetRootNote(track_id, node_id, root_note));
+    }
+
     /// Add a sample layer to a MultiSampler node
     pub fn multi_sampler_add_layer(&mut self, track_id: TrackId, node_id: u32, file_path: String, key_min: u8, key_max: u8, root_key: u8, velocity_min: u8, velocity_max: u8, loop_start: Option<usize>, loop_end: Option<usize>, loop_mode: crate::audio::node_graph::nodes::LoopMode) {
         let _ = self.command_tx.push(Command::MultiSamplerAddLayer(track_id, node_id, file_path, key_min, key_max, root_key, velocity_min, velocity_max, loop_start, loop_end, loop_mode));
     }
 
+    /// Add a sample layer from the audio pool to a MultiSampler node
+    pub fn multi_sampler_add_layer_from_pool(&mut self, track_id: TrackId, node_id: u32, pool_index: usize, key_min: u8, key_max: u8, root_key: u8) {
+        let _ = self.command_tx.push(Command::MultiSamplerAddLayerFromPool(track_id, node_id, pool_index, key_min, key_max, root_key));
+    }
+
     /// Update a MultiSampler layer's configuration
     pub fn multi_sampler_update_layer(&mut self, track_id: TrackId, node_id: u32, layer_index: usize, key_min: u8, key_max: u8, root_key: u8, velocity_min: u8, velocity_max: u8, loop_start: Option<usize>, loop_end: Option<usize>, loop_mode: crate::audio::node_graph::nodes::LoopMode) {
         let _ = self.command_tx.push(Command::MultiSamplerUpdateLayer(track_id, node_id, layer_index, key_min, key_max, root_key, velocity_min, velocity_max, loop_start, loop_end, loop_mode));

daw-backend/src/audio/node_graph/nodes/oscilloscope.rs

@@ -101,8 +101,7 @@ impl OscilloscopeNode {
 
         let inputs = vec![
             NodePort::new("Audio In", SignalType::Audio, 0),
-            NodePort::new("V/oct", SignalType::CV, 1),
-            NodePort::new("CV In", SignalType::CV, 2),
+            NodePort::new("CV In", SignalType::CV, 1),
         ];
 
         let outputs = vec![
@@ -223,13 +222,24 @@ impl AudioNode for OscilloscopeNode {
         let output = &mut outputs[0];
         let len = input.len().min(output.len());
 
-        // Read V/oct input if available and update trigger period
+        // Read CV input if available (port 1) — used for both display and V/Oct triggering
         if inputs.len() > 1 && !inputs[1].is_empty() {
-            self.voct_value = inputs[1][0]; // Use first sample of V/oct input
-            let frequency = Self::voct_to_frequency(self.voct_value);
-            // Calculate period in samples, clamped to reasonable range
-            let period_samples = (sample_rate as f32 / frequency).max(1.0);
-            self.trigger_period = period_samples as usize;
+            let cv_input = inputs[1];
+            let cv_len = len.min(cv_input.len());
+
+            // Check if connected (not NaN sentinel)
+            if cv_len > 0 && !cv_input[0].is_nan() {
+                // Update V/Oct trigger period from CV value
+                self.voct_value = cv_input[0];
+                let frequency = Self::voct_to_frequency(self.voct_value);
+                let period_samples = (sample_rate as f32 / frequency).max(1.0);
+                self.trigger_period = period_samples as usize;
+
+                // Capture CV samples to buffer
+                if let Ok(mut cv_buffer) = self.cv_buffer.lock() {
+                    cv_buffer.write(&cv_input[..cv_len]);
+                }
+            }
         }
 
         // Update sample counter for V/oct triggering
@@ -245,14 +255,6 @@ impl AudioNode for OscilloscopeNode {
             buffer.write(&input[..len]);
         }
 
-        // Capture CV samples if CV input is connected (input 2)
-        if inputs.len() > 2 && !inputs[2].is_empty() {
-            let cv_input = inputs[2];
-            if let Ok(mut cv_buffer) = self.cv_buffer.lock() {
-                cv_buffer.write(&cv_input[..len.min(cv_input.len())]);
-            }
-        }
-
         // Update last sample for trigger detection (use left channel, frame 0)
         if !input.is_empty() {
             self.last_sample = input[0];

daw-backend/src/audio/node_graph/nodes/simple_sampler.rs

@@ -25,6 +25,7 @@ pub struct SimpleSamplerNode {
     gain: f32,
     loop_enabled: bool,
     pitch_shift: f32,       // Additional pitch shift in semitones
+    root_note: u8,          // MIDI note for original pitch playback (default 69 = A4)
 
     inputs: Vec<NodePort>,
     outputs: Vec<NodePort>,
@@ -61,6 +62,7 @@ impl SimpleSamplerNode {
             gain: 1.0,
             loop_enabled: false,
             pitch_shift: 0.0,
+            root_note: 69, // A4 — V/Oct 0.0 from MIDI-to-CV
             inputs,
             outputs,
             parameters,
@@ -101,13 +103,25 @@ impl SimpleSamplerNode {
     }
 
     /// Convert V/oct CV to playback speed multiplier
-    /// 0V = 1.0 (original speed), +1V = 2.0 (one octave up), -1V = 0.5 (one octave down)
+    /// Accounts for root_note: when the incoming MIDI note matches root_note,
+    /// the sample plays at original speed. V/Oct 0.0 = A4 (MIDI 69) by convention.
     fn voct_to_speed(&self, voct: f32) -> f32 {
-        // Add pitch shift parameter
-        let total_semitones = voct * 12.0 + self.pitch_shift;
+        // Offset so root_note plays at original speed
+        let root_offset = (self.root_note as f32 - 69.0) / 12.0;
+        let total_semitones = (voct - root_offset) * 12.0 + self.pitch_shift;
         2.0_f32.powf(total_semitones / 12.0)
     }
 
+    /// Set the root note (MIDI note number for original-pitch playback)
+    pub fn set_root_note(&mut self, note: u8) {
+        self.root_note = note.min(127);
+    }
+
+    /// Get the current root note
+    pub fn root_note(&self) -> u8 {
+        self.root_note
+    }
+
     /// Read sample at playhead with linear interpolation
     fn read_sample(&self, playhead: f32, sample: &[f32]) -> f32 {
         if sample.is_empty() {

daw-backend/src/audio/node_graph/nodes/slew_limiter.rs

@@ -1,4 +1,4 @@
-use crate::audio::node_graph::{AudioNode, NodeCategory, NodePort, Parameter, ParameterUnit, SignalType};
+use crate::audio::node_graph::{AudioNode, NodeCategory, NodePort, Parameter, ParameterUnit, SignalType, cv_input_or_default};
 use crate::audio::midi::MidiEvent;
 
 const PARAM_RISE_TIME: u32 = 0;
@@ -90,9 +90,8 @@ impl AudioNode for SlewLimiterNode {
             return;
         }
 
-        let input = inputs[0];
         let output = &mut outputs[0];
-        let length = input.len().min(output.len());
+        let length = output.len();
 
         // Calculate maximum change per sample
         let sample_duration = 1.0 / sample_rate as f32;
@@ -111,7 +110,9 @@ impl AudioNode for SlewLimiterNode {
         };
 
         for i in 0..length {
-            let target = input[i];
+            // Use cv_input_or_default to handle unconnected inputs (NaN sentinel)
+            // Default to last_value so output holds steady when unconnected
+            let target = cv_input_or_default(inputs, 0, i, self.last_value);
             let difference = target - self.last_value;
 
             let max_change = if difference > 0.0 {

daw-backend/src/command/types.rs

@@ -177,8 +177,14 @@ pub enum Command {
 
     /// Load a sample into a SimpleSampler node (track_id, node_id, file_path)
     SamplerLoadSample(TrackId, u32, String),
+    /// Load a sample from the audio pool into a SimpleSampler node (track_id, node_id, pool_index)
+    SamplerLoadFromPool(TrackId, u32, usize),
+    /// Set the root note (original pitch) for a SimpleSampler node (track_id, node_id, midi_note)
+    SamplerSetRootNote(TrackId, u32, u8),
     /// Add a sample layer to a MultiSampler node (track_id, node_id, file_path, key_min, key_max, root_key, velocity_min, velocity_max, loop_start, loop_end, loop_mode)
     MultiSamplerAddLayer(TrackId, u32, String, u8, u8, u8, u8, u8, Option<usize>, Option<usize>, LoopMode),
+    /// Add a sample layer from the audio pool to a MultiSampler node (track_id, node_id, pool_index, key_min, key_max, root_key)
+    MultiSamplerAddLayerFromPool(TrackId, u32, usize, u8, u8, u8),
     /// Update a MultiSampler layer's configuration (track_id, node_id, layer_index, key_min, key_max, root_key, velocity_min, velocity_max, loop_start, loop_end, loop_mode)
     MultiSamplerUpdateLayer(TrackId, u32, usize, u8, u8, u8, u8, u8, Option<usize>, Option<usize>, LoopMode),
     /// Remove a layer from a MultiSampler node (track_id, node_id, layer_index)

lightningbeam-ui/egui_node_graph2/src/editor_ui.rs

@@ -332,7 +332,9 @@ where
                 ports: &SlotMap<Key, Value>,
                 port_locations: &PortLocations,
                 cursor_pos: Pos2,
+                zoom: f32,
             ) -> Pos2 {
+                let snap_distance = DISTANCE_TO_CONNECT * zoom;
                 ports
                     .iter()
                     .find_map(|(port_id, _)| {
@@ -352,7 +354,7 @@ where
                                             .unwrap()
                                     })
                                     .filter(|nearest_hook| {
-                                        nearest_hook.distance(cursor_pos) < DISTANCE_TO_CONNECT
+                                        nearest_hook.distance(cursor_pos) < snap_distance
                                     })
                                     .copied()
                             })
@@ -372,6 +374,7 @@ where
                         &self.graph.inputs,
                         &port_locations,
                         cursor_pos,
+                        self.pan_zoom.zoom,
                     ),
                 ),
                 AnyParameterId::Input(_) => (
@@ -381,6 +384,7 @@ where
                         &self.graph.outputs,
                         &port_locations,
                         cursor_pos,
+                        self.pan_zoom.zoom,
                     ),
                     start_pos,
                 ),

lightningbeam-ui/lightningbeam-editor/src/panes/node_graph/graph_data.rs

@@ -135,20 +135,85 @@ impl NodeTemplate {
 #[derive(Clone, Debug, Serialize, Deserialize)]
 pub struct NodeData {
     pub template: NodeTemplate,
+    /// Display name of loaded sample (for SimpleSampler/MultiSampler nodes)
+    #[serde(default)]
+    pub sample_display_name: Option<String>,
+    /// Root note (MIDI note number) for original-pitch playback (default 69 = A4)
+    #[serde(default = "default_root_note")]
+    pub root_note: u8,
 }
 
+fn default_root_note() -> u8 { 69 }
+
 /// Cached oscilloscope waveform data for rendering in node body
 pub struct OscilloscopeCache {
     pub audio: Vec<f32>,
     pub cv: Vec<f32>,
 }
 
+/// Info about an audio clip available for sampler selection
+pub struct SamplerClipInfo {
+    pub name: String,
+    pub pool_index: usize,
+}
+
+/// Info about an asset folder available for multi-sampler
+pub struct SamplerFolderInfo {
+    pub folder_id: uuid::Uuid,
+    pub name: String,
+    /// Pool indices of audio clips in this folder
+    pub clip_pool_indices: Vec<(String, usize)>,
+}
+
+/// Pending sampler load request from bottom_ui(), handled by the node graph pane
+pub enum PendingSamplerLoad {
+    /// Load a single clip from the audio pool into a SimpleSampler
+    SimpleFromPool { node_id: NodeId, backend_node_id: u32, pool_index: usize, name: String },
+    /// Open a file dialog to load into a SimpleSampler
+    SimpleFromFile { node_id: NodeId, backend_node_id: u32 },
+    /// Load a single clip from the audio pool as a MultiSampler layer
+    MultiFromPool { node_id: NodeId, backend_node_id: u32, pool_index: usize, name: String },
+    /// Load all clips in a folder as MultiSampler layers
+    MultiFromFolder { node_id: NodeId, folder_id: uuid::Uuid },
+    /// Open a file/folder dialog to load into a MultiSampler
+    MultiFromFilesystem { node_id: NodeId, backend_node_id: u32 },
+}
+
 /// Custom graph state - can track selected nodes, etc.
-#[derive(Default)]
 pub struct GraphState {
     pub active_node: Option<NodeId>,
     /// Oscilloscope data cached per node, populated before draw_graph_editor()
     pub oscilloscope_data: HashMap<NodeId, OscilloscopeCache>,
+    /// Audio clips available for sampler selection, populated before draw
+    pub available_clips: Vec<SamplerClipInfo>,
+    /// Asset folders available for multi-sampler, populated before draw
+    pub available_folders: Vec<SamplerFolderInfo>,
+    /// Pending sample load request from bottom_ui popup
+    pub pending_sampler_load: Option<PendingSamplerLoad>,
+    /// Search text for the sampler clip picker popup
+    pub sampler_search_text: String,
+    /// Mapping from frontend NodeId to backend node index, populated before draw
+    pub node_backend_ids: HashMap<NodeId, u32>,
+    /// Pending root note changes from bottom_ui (node_id, backend_node_id, new_root_note)
+    pub pending_root_note_changes: Vec<(NodeId, u32, u8)>,
+    /// Time scale per oscilloscope node (in milliseconds)
+    pub oscilloscope_time_scale: HashMap<NodeId, f32>,
+}
+
+impl Default for GraphState {
+    fn default() -> Self {
+        Self {
+            active_node: None,
+            oscilloscope_data: HashMap::new(),
+            available_clips: Vec::new(),
+            available_folders: Vec::new(),
+            pending_sampler_load: None,
+            sampler_search_text: String::new(),
+            node_backend_ids: HashMap::new(),
+            pending_root_note_changes: Vec::new(),
+            oscilloscope_time_scale: HashMap::new(),
+        }
+    }
 }
 
 /// User response type (empty for now)
@@ -333,7 +398,7 @@ impl NodeTemplateTrait for NodeTemplate {
     }
 
     fn user_data(&self, _user_state: &mut Self::UserState) -> Self::NodeData {
-        NodeData { template: *self }
+        NodeData { template: *self, sample_display_name: None, root_note: 69 }
     }
 
     fn build_node(
@@ -498,6 +563,7 @@ impl NodeTemplateTrait for NodeTemplate {
                 graph.add_output_param(node_id, "Audio Out".into(), DataType::Audio);
             }
             NodeTemplate::SimpleSampler => {
+                graph.add_input_param(node_id, "V/Oct".into(), DataType::CV, ValueType::float(0.0), InputParamKind::ConnectionOnly, true);
                 graph.add_input_param(node_id, "Gate".into(), DataType::CV, ValueType::float(0.0), InputParamKind::ConnectionOnly, true);
                 graph.add_output_param(node_id, "Audio Out".into(), DataType::Audio);
             }
@@ -781,6 +847,14 @@ impl WidgetValueTrait for ValueType {
     }
 }
 
+const NOTE_NAMES: [&str; 12] = ["C", "C#", "D", "D#", "E", "F", "F#", "G", "G#", "A", "A#", "B"];
+
+fn midi_note_name(note: u8) -> String {
+    let octave = (note as i32 / 12) - 1;
+    let name = NOTE_NAMES[note as usize % 12];
+    format!("{}{}", name, octave)
+}
+
 // Implement NodeDataTrait for custom node UI (optional)
 impl NodeDataTrait for NodeData {
     type Response = UserResponse;
@@ -798,7 +872,123 @@ impl NodeDataTrait for NodeData {
     where
         Self::Response: UserResponseTrait,
     {
-        if self.template == NodeTemplate::Oscilloscope {
+        if self.template == NodeTemplate::SimpleSampler || self.template == NodeTemplate::MultiSampler {
+            let is_multi = self.template == NodeTemplate::MultiSampler;
+            let backend_node_id = user_state.node_backend_ids.get(&node_id).copied().unwrap_or(0);
+            let default_text = if is_multi { "Select samples..." } else { "Select sample..." };
+            let button_text = self.sample_display_name.as_deref().unwrap_or(default_text);
+
+            let button = ui.button(button_text);
+            if button.clicked() {
+                user_state.sampler_search_text.clear();
+            }
+            let popup_id = egui::Popup::default_response_id(&button);
+
+            let mut close_popup = false;
+            egui::Popup::from_toggle_button_response(&button)
+                .close_behavior(egui::PopupCloseBehavior::CloseOnClickOutside)
+                .show(|ui| {
+                ui.set_min_width(200.0);
+                ui.text_edit_singleline(&mut user_state.sampler_search_text);
+                ui.separator();
+                let search = user_state.sampler_search_text.to_lowercase();
+
+                // Folders section (multi-sampler only)
+                if is_multi && !user_state.available_folders.is_empty() {
+                    ui.label(egui::RichText::new("Folders").small().weak());
+                    for folder in &user_state.available_folders {
+                        if !search.is_empty() && !folder.name.to_lowercase().contains(&search) {
+                            continue;
+                        }
+                        let label = format!("📁 {} ({} clips)", folder.name, folder.clip_pool_indices.len());
+                        if ui.selectable_label(false, label).clicked() {
+                            user_state.pending_sampler_load = Some(PendingSamplerLoad::MultiFromFolder {
+                                node_id,
+                                folder_id: folder.folder_id,
+                            });
+                            close_popup = true;
+                        }
+                    }
+                    ui.separator();
+                }
+
+                // Audio clips list
+                if is_multi {
+                    ui.label(egui::RichText::new("Audio Clips").small().weak());
+                }
+                egui::ScrollArea::vertical().max_height(200.0).show(ui, |ui| {
+                    for clip in &user_state.available_clips {
+                        if !search.is_empty() && !clip.name.to_lowercase().contains(&search) {
+                            continue;
+                        }
+                        if ui.selectable_label(false, &clip.name).clicked() {
+                            if is_multi {
+                                user_state.pending_sampler_load = Some(PendingSamplerLoad::MultiFromPool {
+                                    node_id,
+                                    backend_node_id,
+                                    pool_index: clip.pool_index,
+                                    name: clip.name.clone(),
+                                });
+                            } else {
+                                user_state.pending_sampler_load = Some(PendingSamplerLoad::SimpleFromPool {
+                                    node_id,
+                                    backend_node_id,
+                                    pool_index: clip.pool_index,
+                                    name: clip.name.clone(),
+                                });
+                            }
+                            close_popup = true;
+                        }
+                    }
+                });
+                ui.separator();
+                if ui.button("Open...").clicked() {
+                    if is_multi {
+                        user_state.pending_sampler_load = Some(PendingSamplerLoad::MultiFromFilesystem {
+                            node_id,
+                            backend_node_id,
+                        });
+                    } else {
+                        user_state.pending_sampler_load = Some(PendingSamplerLoad::SimpleFromFile {
+                            node_id,
+                            backend_node_id,
+                        });
+                    }
+                    close_popup = true;
+                }
+            });
+
+            if close_popup {
+                egui::Popup::close_id(ui.ctx(), popup_id);
+            }
+
+            // Root note selector
+            ui.horizontal(|ui| {
+                ui.label(egui::RichText::new("Root:").weak());
+                let note_name = midi_note_name(self.root_note);
+                let root_btn = ui.button(&note_name);
+                let root_popup_id = egui::Popup::default_response_id(&root_btn);
+                let mut close_root = false;
+                egui::Popup::from_toggle_button_response(&root_btn)
+                    .close_behavior(egui::PopupCloseBehavior::CloseOnClickOutside)
+                    .show(|ui| {
+                    ui.set_min_width(120.0);
+                    egui::ScrollArea::vertical().max_height(200.0).show(ui, |ui| {
+                        // Show notes from C1 (24) to C7 (96)
+                        for note in (24..=96).rev() {
+                            let name = midi_note_name(note);
+                            if ui.selectable_label(note == self.root_note, &name).clicked() {
+                                user_state.pending_root_note_changes.push((node_id, backend_node_id, note));
+                                close_root = true;
+                            }
+                        }
+                    });
+                });
+                if close_root {
+                    egui::Popup::close_id(ui.ctx(), root_popup_id);
+                }
+            });
+        } else if self.template == NodeTemplate::Oscilloscope {
             let size = egui::vec2(200.0, 80.0);
             let (rect, _) = ui.allocate_exact_size(size, egui::Sense::hover());
             let painter = ui.painter_at(rect);
@@ -834,6 +1024,15 @@ impl NodeDataTrait for NodeData {
                     painter.add(egui::Shape::line(points, egui::Stroke::new(1.5, egui::Color32::from_rgb(0xFF, 0x98, 0x00))));
                 }
             }
+
+            // Time window slider
+            let time_ms = user_state.oscilloscope_time_scale.entry(node_id).or_insert(100.0);
+            ui.horizontal(|ui| {
+                ui.spacing_mut().slider_width = 140.0;
+                ui.add(egui::Slider::new(time_ms, 10.0..=1000.0)
+                    .suffix(" ms")
+                    .logarithmic(true));
+            });
         } else {
             ui.label("");
         }

lightningbeam-ui/lightningbeam-editor/src/panes/node_graph/mod.rs

@@ -560,6 +560,100 @@ impl NodeGraphPane {
         }
     }
 
+    fn handle_pending_sampler_load(
+        &mut self,
+        load: graph_data::PendingSamplerLoad,
+        shared: &mut crate::panes::SharedPaneState,
+    ) {
+        let backend_track_id = match self.backend_track_id {
+            Some(id) => id,
+            None => return,
+        };
+        let controller_arc = match &shared.audio_controller {
+            Some(c) => std::sync::Arc::clone(c),
+            None => return,
+        };
+
+        match load {
+            graph_data::PendingSamplerLoad::SimpleFromPool { node_id, backend_node_id, pool_index, name } => {
+                let mut controller = controller_arc.lock().unwrap();
+                controller.sampler_load_from_pool(backend_track_id, backend_node_id, pool_index);
+                if let Some(node) = self.state.graph.nodes.get_mut(node_id) {
+                    node.user_data.sample_display_name = Some(name);
+                }
+            }
+            graph_data::PendingSamplerLoad::SimpleFromFile { node_id, backend_node_id } => {
+                if let Some(path) = rfd::FileDialog::new()
+                    .add_filter("Audio", &["wav", "flac", "mp3", "ogg", "aiff"])
+                    .pick_file()
+                {
+                    let path_str = path.to_string_lossy().to_string();
+                    let file_name = path.file_stem()
+                        .map(|s| s.to_string_lossy().to_string())
+                        .unwrap_or_else(|| "Sample".to_string());
+                    let mut controller = controller_arc.lock().unwrap();
+                    controller.sampler_load_sample(backend_track_id, backend_node_id, path_str);
+                    if let Some(node) = self.state.graph.nodes.get_mut(node_id) {
+                        node.user_data.sample_display_name = Some(file_name);
+                    }
+                }
+            }
+            graph_data::PendingSamplerLoad::MultiFromPool { node_id, backend_node_id, pool_index, name } => {
+                let mut controller = controller_arc.lock().unwrap();
+                // Add as a single layer spanning full key range, root_key = 60 (C4)
+                controller.multi_sampler_add_layer_from_pool(
+                    backend_track_id, backend_node_id, pool_index,
+                    0, 127, 60,
+                );
+                if let Some(node) = self.state.graph.nodes.get_mut(node_id) {
+                    node.user_data.sample_display_name = Some(name);
+                }
+            }
+            graph_data::PendingSamplerLoad::MultiFromFolder { node_id, folder_id } => {
+                // Find folder clips from available_folders
+                let folder_clips: Vec<(String, usize)> = self.user_state.available_folders.iter()
+                    .find(|f| f.folder_id == folder_id)
+                    .map(|f| f.clip_pool_indices.clone())
+                    .unwrap_or_default();
+
+                if !folder_clips.is_empty() {
+                    // TODO: Add MultiSamplerLoadFromPool command to avoid disk re-reads.
+                    // For now, folder loading is a placeholder — the UI is wired up but
+                    // loading multi-sampler layers from pool requires a new backend command.
+                    let folder_name = self.user_state.available_folders.iter()
+                        .find(|f| f.folder_id == folder_id)
+                        .map(|f| f.name.clone())
+                        .unwrap_or_else(|| "Folder".to_string());
+                    eprintln!("MultiSampler folder load not yet implemented for folder: {}", folder_name);
+                    if let Some(node) = self.state.graph.nodes.get_mut(node_id) {
+                        node.user_data.sample_display_name = Some(format!("📁 {}", folder_name));
+                    }
+                }
+            }
+            graph_data::PendingSamplerLoad::MultiFromFilesystem { node_id, backend_node_id } => {
+                if let Some(path) = rfd::FileDialog::new()
+                    .add_filter("Audio", &["wav", "flac", "mp3", "ogg", "aiff"])
+                    .pick_file()
+                {
+                    let path_str = path.to_string_lossy().to_string();
+                    let file_name = path.file_stem()
+                        .map(|s| s.to_string_lossy().to_string())
+                        .unwrap_or_else(|| "Sample".to_string());
+                    let mut controller = controller_arc.lock().unwrap();
+                    // Add as layer spanning full key range
+                    controller.multi_sampler_add_layer(
+                        backend_track_id, backend_node_id, path_str,
+                        0, 127, 60, 0, 127, None, None,
+                        daw_backend::audio::node_graph::nodes::LoopMode::OneShot,
+                    );
+                    if let Some(node) = self.state.graph.nodes.get_mut(node_id) {
+                        node.user_data.sample_display_name = Some(file_name);
+                    }
+                }
+            }
+        }
+    }
+
     fn check_parameter_changes(&mut self, shared: &mut crate::panes::SharedPaneState) {
         // Check all input parameters for value changes
         let mut _checked_count = 0;
@@ -1554,7 +1648,7 @@ impl NodeGraphPane {
                 label: group.name.clone(),
                 inputs: vec![],
                 outputs: vec![],
-                user_data: NodeData { template: NodeTemplate::Group },
+                user_data: NodeData { template: NodeTemplate::Group, sample_display_name: None, root_note: 69 },
             });
 
             // Add dynamic input ports based on boundary inputs
@@ -1626,7 +1720,7 @@ impl NodeGraphPane {
                     label: "Group Input".to_string(),
                     inputs: vec![],
                     outputs: vec![],
-                    user_data: NodeData { template: NodeTemplate::Group },
+                    user_data: NodeData { template: NodeTemplate::Group, sample_display_name: None, root_note: 69 },
                 });
 
                 for bc in &scope_group.boundary_inputs {
@@ -1673,7 +1767,7 @@ impl NodeGraphPane {
                     label: "Group Output".to_string(),
                     inputs: vec![],
                     outputs: vec![],
-                    user_data: NodeData { template: NodeTemplate::Group },
+                    user_data: NodeData { template: NodeTemplate::Group, sample_display_name: None, root_note: 69 },
                 });
 
                 for bc in &scope_group.boundary_outputs {
@@ -1866,7 +1960,7 @@ impl NodeGraphPane {
             label: label.to_string(),
             inputs: vec![],
             outputs: vec![],
-            user_data: NodeData { template: node_template },
+            user_data: NodeData { template: node_template, sample_display_name: None, root_note: 69 },
         });
 
         node_template.build_node(&mut self.state.graph, &mut self.user_state, frontend_id);
@@ -2042,10 +2136,14 @@ impl crate::panes::PaneRenderer for NodeGraphPane {
 
                     let mut controller = audio_controller.lock().unwrap();
                     for (node_id, backend_node_id) in oscilloscope_nodes {
+                        // Calculate sample count from per-node time scale (default 100ms)
+                        let time_ms = self.user_state.oscilloscope_time_scale
+                            .get(&node_id).copied().unwrap_or(100.0);
+                        let sample_count = ((time_ms / 1000.0) * 48000.0) as usize;
                         let result = if let Some(va_id) = va_backend_id {
-                            controller.query_voice_oscilloscope_data(backend_track_id, va_id, backend_node_id, 4800)
+                            controller.query_voice_oscilloscope_data(backend_track_id, va_id, backend_node_id, sample_count)
                         } else {
-                            controller.query_oscilloscope_data(backend_track_id, backend_node_id, 4800)
+                            controller.query_oscilloscope_data(backend_track_id, backend_node_id, sample_count)
                         };
                         if let Ok(data) = result {
                             self.user_state.oscilloscope_data.insert(node_id, graph_data::OscilloscopeCache {
@@ -2172,6 +2270,55 @@ impl crate::panes::PaneRenderer for NodeGraphPane {
             let zoom_before = self.state.pan_zoom.zoom;
             let pan_before = self.state.pan_zoom.pan;
 
+            // Populate sampler clip list and node backend ID map for bottom_ui()
+            {
+                use lightningbeam_core::clip::AudioClipType;
+
+                let doc = shared.action_executor.document();
+
+                // Available audio clips
+                self.user_state.available_clips = doc.audio_clips.values()
+                    .filter_map(|clip| match &clip.clip_type {
+                        AudioClipType::Sampled { audio_pool_index } => Some(graph_data::SamplerClipInfo {
+                            name: clip.name.clone(),
+                            pool_index: *audio_pool_index,
+                        }),
+                        _ => None,
+                    })
+                    .collect();
+                self.user_state.available_clips.sort_by(|a, b| a.name.to_lowercase().cmp(&b.name.to_lowercase()));
+
+                // Available folders (with their contained audio clips)
+                self.user_state.available_folders = doc.audio_folders.folders.values()
+                    .map(|folder| {
+                        let clips_in_folder: Vec<(String, usize)> = doc.audio_clips.values()
+                            .filter(|clip| clip.folder_id == Some(folder.id))
+                            .filter_map(|clip| match &clip.clip_type {
+                                AudioClipType::Sampled { audio_pool_index } => Some((clip.name.clone(), *audio_pool_index)),
+                                _ => None,
+                            })
+                            .collect();
+                        graph_data::SamplerFolderInfo {
+                            folder_id: folder.id,
+                            name: folder.name.clone(),
+                            clip_pool_indices: clips_in_folder,
+                        }
+                    })
+                    .filter(|f| !f.clip_pool_indices.is_empty())
+                    .collect();
+                self.user_state.available_folders.sort_by(|a, b| a.name.to_lowercase().cmp(&b.name.to_lowercase()));
+
+                // Node backend ID map
+                self.user_state.node_backend_ids = self.node_id_map.iter()
+                    .map(|(&node_id, backend_id)| {
+                        let id = match backend_id {
+                            BackendNodeId::Audio(idx) => idx.index() as u32,
+                        };
+                        (node_id, id)
+                    })
+                    .collect();
+            }
+
             // Draw dot grid background with pan/zoom
             let pan_zoom = &self.state.pan_zoom;
             Self::draw_dot_grid_background(ui, graph_rect, bg_color, grid_color, pan_zoom);
@@ -2204,6 +2351,27 @@ impl crate::panes::PaneRenderer for NodeGraphPane {
             self.last_node_rects = graph_response.node_rects.clone();
             self.handle_graph_response(graph_response, shared, graph_rect);
 
+            // Handle pending sampler load requests from bottom_ui()
+            if let Some(load) = self.user_state.pending_sampler_load.take() {
+                self.handle_pending_sampler_load(load, shared);
+            }
+
+            // Handle pending root note changes
+            if !self.user_state.pending_root_note_changes.is_empty() {
+                let changes: Vec<_> = self.user_state.pending_root_note_changes.drain(..).collect();
+                if let Some(backend_track_id) = self.track_id.and_then(|tid| shared.layer_to_track_map.get(&tid).copied()) {
+                    if let Some(controller_arc) = &shared.audio_controller {
+                        let mut controller = controller_arc.lock().unwrap();
+                        for (node_id, backend_node_id, root_note) in changes {
+                            controller.sampler_set_root_note(backend_track_id, backend_node_id, root_note);
+                            if let Some(node) = self.state.graph.nodes.get_mut(node_id) {
+                                node.user_data.root_note = root_note;
+                            }
+                        }
+                    }
+                }
+            }
+
             // Detect right-click on nodes — intercept the library's node finder and show our context menu instead
             {
                 let secondary_clicked = ui.input(|i| i.pointer.secondary_released());