signal_to_timeline.rs

shared/src/lib.rs

@@ -3,6 +3,9 @@ use moonlight::*;
 mod var_format;
 pub use var_format::VarFormat;
 
+mod signal_to_timeline;
+pub use signal_to_timeline::signal_to_timeline;
+
 pub mod wellen_helpers;
 
 #[derive(Serialize, Deserialize, Debug, Default)]

shared/src/signal_to_timeline.rs

@@ -0,0 +1,72 @@
+use crate::*;
+
+pub fn signal_to_timeline(
+    signal: &wellen::Signal,
+    time_table: &[wellen::Time],
+    screen_width: u32,
+    block_height: u32,
+    var_format: VarFormat,
+) -> Timeline {
+    const MIN_BLOCK_WIDTH: u32 = 3;
+    // Courier New, 16px, sync with `label_style` in `pixi_canvas.rs`
+    const LETTER_WIDTH: f64 = 9.61;
+    const LETTER_HEIGHT: u32 = 18;
+    const LABEL_X_PADDING: u32 = 10;
+
+    let Some(last_time) = time_table.last().copied() else {
+        return Timeline::default();
+    };
+
+    let last_time = last_time as f64;
+    let screen_width = screen_width as f64;
+
+    let mut x_value_pairs = signal
+        .iter_changes()
+        .map(|(index, value)| {
+            let index = index as usize;
+            let time = time_table[index] as f64;
+            let x = time / last_time * screen_width;
+            (x, value)
+        })
+        .peekable();
+
+    // @TODO parallelize?
+    let mut blocks = Vec::new();
+    while let Some((block_x, value)) = x_value_pairs.next() {
+        let next_block_x = if let Some((next_block_x, _)) = x_value_pairs.peek() {
+            *next_block_x
+        } else {
+            screen_width
+        };
+
+        let block_width = (next_block_x - block_x) as u32;
+        if block_width < MIN_BLOCK_WIDTH {
+            continue;
+        }
+
+        // @TODO cache?
+        let value = var_format.format(value);
+
+        let value_width = (value.chars().count() as f64 * LETTER_WIDTH) as u32;
+        // @TODO Ellipsis instead of hiding?
+        let label = if (value_width + (2 * LABEL_X_PADDING)) <= block_width {
+            Some(TimeLineBlockLabel {
+                text: value,
+                x: (block_width - value_width) / 2,
+                y: (block_height - LETTER_HEIGHT) / 2,
+            })
+        } else {
+            None
+        };
+
+        let block = TimelineBlock {
+            x: block_x as u32,
+            width: block_width,
+            height: block_height,
+            label,
+        };
+        blocks.push(block);
+    }
+
+    Timeline { blocks }
+}