first commit

src/patterns.rs

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+//! H7CAD hatch pattern catalog — loaded from `assets/patterns/H7CAD.pat`.
+//!
+//! PAT line format:  `angle, x0, y0, dx, dy [, dash1, dash2, ...]`
+//!   - `angle`      line direction in degrees
+//!   - `x0, y0`     origin of the first line in the family
+//!   - `dx, dy`     step vector to the next parallel line
+//!   - `dash…`      positive = dash length, negative = gap length (omit = solid)
+
+use std::sync::OnceLock;
+
+const PAT_SRC: &str = include_str!("../assets/patterns/H7CAD.pat");
+
+// ── Public types ──────────────────────────────────────────────────────────
+
+/// One line family inside a hatch pattern.
+#[derive(Clone, Debug)]
+pub struct PatLineDef {
+    /// Line direction in degrees.
+    pub angle_deg: f32,
+    /// Origin of the first line in the family.
+    pub x0: f32,
+    pub y0: f32,
+    /// Step vector to the next parallel line.
+    pub dx: f32,
+    pub dy: f32,
+    /// Dash/gap sequence (positive = dash, negative = gap, empty = solid).
+    pub dashes: Vec<f32>,
+}
+
+/// One parsed hatch pattern.
+#[derive(Clone, Debug)]
+pub struct PatternDef {
+    pub name: String,
+    pub description: String,
+    pub lines: Vec<PatLineDef>,
+}
+
+// ── Static catalog ────────────────────────────────────────────────────────
+
+static CATALOG: OnceLock<Vec<PatternDef>> = OnceLock::new();
+
+/// All parsed patterns, in file order.
+pub fn catalog() -> &'static [PatternDef] {
+    CATALOG.get_or_init(|| parse(PAT_SRC))
+}
+
+// ── Geometry helper ───────────────────────────────────────────────────────
+
+// ── Parser ────────────────────────────────────────────────────────────────
+
+fn parse(src: &str) -> Vec<PatternDef> {
+    let mut result = Vec::new();
+    let mut cur_name = String::new();
+    let mut cur_desc = String::new();
+    let mut cur_lines: Vec<PatLineDef> = Vec::new();
+    let mut in_pattern = false;
+
+    let flush = |name: &mut String,
+                 desc: &mut String,
+                 lines: &mut Vec<PatLineDef>,
+                 result: &mut Vec<PatternDef>| {
+        if !lines.is_empty() {
+            result.push(PatternDef {
+                name: std::mem::take(name),
+                description: std::mem::take(desc),
+                lines: std::mem::take(lines),
+            });
+        }
+        *name = String::new();
+        *desc = String::new();
+    };
+
+    for raw in src.lines() {
+        let line = raw.trim();
+
+        // Skip blanks and comments.
+        if line.is_empty() || line.starts_with(';') {
+            continue;
+        }
+
+        if let Some(rest) = line.strip_prefix('*') {
+            // Flush previous pattern.
+            flush(&mut cur_name, &mut cur_desc, &mut cur_lines, &mut result);
+            in_pattern = true;
+
+            // Header: *NAME[,Description]
+            if let Some((name, desc)) = rest.split_once(',') {
+                cur_name = name.trim().to_string();
+                cur_desc = desc.trim().to_string();
+            } else {
+                cur_name = rest.trim().to_string();
+                cur_desc = String::new();
+            }
+        } else if in_pattern {
+            // Pattern line: angle, x0, y0, dx, dy [, d1, d2, ...]
+            // Strip inline comments.
+            let data = line.split(';').next().unwrap_or("").trim();
+            if data.is_empty() {
+                continue;
+            }
+
+            let parts: Vec<f32> = data
+                .split(',')
+                .filter_map(|s| s.trim().parse().ok())
+                .collect();
+
+            if parts.len() >= 5 {
+                cur_lines.push(PatLineDef {
+                    angle_deg: parts[0],
+                    x0: parts[1],
+                    y0: parts[2],
+                    dx: parts[3],
+                    dy: parts[4],
+                    dashes: parts[5..].to_vec(),
+                });
+            }
+        }
+    }
+
+    // Flush last pattern.
+    flush(&mut cur_name, &mut cur_desc, &mut cur_lines, &mut result);
+
+    result
+}