update docs

README.md

@@ -2,64 +2,57 @@
 
 A lightweight, debug-only telemetry profiler for Rust applications. Shows thread activity and call stack hierarchy in real-time.
 
-Inspired by RAD Telemetry - built in ~1200 LOC with 'minimal' dependencies (for a Rust project).
+Inspired by RAD Telemetry - built in ~1200 LOC with minimal dependencies.
 
 ## Features
 
-- **Icicle graph** showing call stack hierarchy (top half)
-- **Thread timeline** showing per-thread activity over time (bottom half)
+- **Unified thread tracks** with expandable call stacks (click headers to toggle)
+- **Collapsed view** shows when threads are active (easy to spot blocking)
+- **Expanded view** shows full call stack hierarchy with flame graph visualization
+- **Ongoing span support** for long-running functions (main loops, render threads)
+- **Pause mechanism** to freeze your application for inspection (Space bar)
 - **Monokai color palette** for easy visual distinction
-- **Pause mechanism** to freeze your application for inspection
+- **Incremental tree building** - only processes new spans each frame
 - **Ringbuffer storage** (~16MB, 1M events) for recent history
 - **Lock-free event recording** via MPSC channels
 
 ## Dependencies
 
-Only 7 dependencies (~70 total including transitive):
+Only 7 direct dependencies (~70 total including transitive):
 - `minifb` - Window and framebuffer
 - `crossbeam-channel` - Lock-free MPSC
 - `once_cell` - Lazy statics
-- `fontdue`
-- `procmacro2`
-- `syn`
-- `quote`
+- `fontdue` - Font rasterization
+- `procmacro2`, `syn`, `quote` - Proc macros
 
 ## Usage
 
 ### Add to your `Cargo.toml`:
-
 ```toml
 [dependencies]
 teleprof = { path = "../teleprof" }
 ```
 
 ### In your code:
-
 ```rust
 fn main() {
     // Start the profiler window (separate thread)
     #[cfg(debug_assertions)]
     teleprof::start();
     
-    // Your application code
+    // Name your thread (optional, shows in UI)
+    #[cfg(debug_assertions)]
+    teleprof::set_thread_name("main");
+    
     game_loop();
 }
 
 fn game_loop() {
     loop {
-        // Profile a scope
-        teleprof::span!("game_loop");
+        teleprof::span!("main_frame");
         
         update();
         render();
-        
-        // Check if paused (optional)
-        if teleprof::PAUSE.try_lock().is_err() {
-            // Wait until unpaused
-            while teleprof::PAUSE.try_lock().is_err() {
-                std::thread::sleep(std::time::Duration::from_millis(100));
-            }
-        }
     }
 }
 
@@ -74,18 +67,13 @@ fn render() {
 }
 ```
 
-### For closures:
-
-```rust
-let work = || {
-    teleprof::span!("my_closure");
-    // work...
-};
-```
-
 ## Controls
 
-- **Space**: Toggle pause (acquires `PAUSE` lock to freeze your app)
+- **Space**: Toggle pause (freezes ongoing spans at current time)
+- **Left click + drag**: Box select to zoom (click background not function)
+- **Right click + drag**: Pan timeline
+- **Scroll**: Zoom timeline horizontally
+- **Click track header**: Expand/collapse thread's call stack
 - **Escape**: Close profiler window
 
 ## How it works
@@ -94,19 +82,20 @@ let work = || {
 2. When the guard drops, sends `SpanEnd`
 3. Events are sent via lock-free MPSC channel
 4. Window thread drains events into a fixed-size ringbuffer
-5. Renders icicle graph (call hierarchy) and timeline (per-thread activity)
+5. Incrementally builds per-thread call trees (only processes new spans)
+6. Renders unified thread tracks with expandable call stacks
 
 ## Design Goals
 
-- **Minimal overhead**: Lock-free event recording
+- **Minimal overhead**: Lock-free event recording, incremental tree building
 - **Debug-only**: Compile out in release builds with `#[cfg(debug_assertions)]`
 - **Separate window**: Doesn't interfere with your app's rendering
 - **Simple API**: Just `span!("name")` and you're done
+- **Handle any thread pattern**: Long-lived, short-lived, thread pools (Rayon, etc.)
 
 ## Examples
 
 Run the included examples:
-
 ```bash
 # Multi-threaded physics simulation
 cargo run --example demo

teleprof/src/lib.rs

@@ -1372,7 +1372,7 @@ mod window {
         
         draw_text(framebuffer, width, text_x, text_y, hover.name, font, 14.0, 0xFFFFFF);
         draw_text(framebuffer, width, text_x, text_y + 20, 
-                 &format!("Duration: {:.2} μs", hover.duration_us), font, 12.0, 0xCCCCCC);
+                 &format!("Duration: {} μs", format_number(hover.duration_us)), font, 12.0, 0xCCCCCC);
         draw_text(framebuffer, width, text_x, text_y + 38,
                  &format!("Thread: {}", hover.thread_id), font, 12.0, 0xCCCCCC);
         draw_text(framebuffer, width, text_x, text_y + 56,
@@ -1409,17 +1409,23 @@ mod window {
         size: f32,
         color: u32,
     ) {
-        let mut cursor_x = x as f32;
+        let mut cursor_x = x as i32;
         
         for ch in text.chars() {
             let (metrics, bitmap) = font.rasterize(ch, size);
             
+            // xmin is the offset from the cursor to the left edge of the glyph
+            // ymin is the offset from the baseline to the bottom edge of the glyph
+            // The glyph's position is: (cursor + xmin, baseline - height - ymin)
+            let glyph_x = (cursor_x + metrics.xmin).max(0) as usize;
+            let glyph_y = (size as i32 + y as i32 - metrics.height as i32 - metrics.ymin).max(0) as usize;
+            
             for (i, &alpha) in bitmap.iter().enumerate() {
                 if alpha > 0 {
-                    let px = cursor_x as usize + (i % metrics.width);
-                    let py = y + (i / metrics.width) + (size as usize - metrics.height);
+                    let px = glyph_x + (i % metrics.width);
+                    let py = glyph_y + (i / metrics.width);
                     
-                    if px < width {
+                    if px < width && py < framebuffer.len() / width {
                         let idx = py * width + px;
                         if idx < framebuffer.len() {
                             let alpha_f = alpha as f32 / 255.0;
@@ -1430,7 +1436,8 @@ mod window {
                 }
             }
             
-            cursor_x += metrics.advance_width;
+            // Advance cursor by the advance_width (includes spacing)
+            cursor_x += metrics.advance_width as i32;
         }
     }
 
@@ -1438,4 +1445,26 @@ mod window {
         let hash = name.bytes().fold(0u32, |acc, b| acc.wrapping_mul(31).wrapping_add(b as u32));
         COLORS[(hash as usize) % COLORS.len()]
     }
+    
+    // Format a number with thousands separators
+    fn format_number(n: f64) -> String {
+        let s = format!("{:.2}", n);
+        let parts: Vec<&str> = s.split('.').collect();
+        let integer_part = parts[0];
+        let decimal_part = if parts.len() > 1 { parts[1] } else { "00" };
+        
+        // Add commas to integer part
+        let mut result = String::new();
+        let chars: Vec<char> = integer_part.chars().collect();
+        for (i, ch) in chars.iter().enumerate() {
+            if i > 0 && (chars.len() - i) % 3 == 0 {
+                result.push(',');
+            }
+            result.push(*ch);
+        }
+        
+        result.push('.');
+        result.push_str(decimal_part);
+        result
+    }
 }