Feature mirrors and patterns: preserve replay and add Flip/Center placement (#1619)

Thanks @Karl-VonRichter.

crates/doc/src/document.rs

@@ -1721,6 +1721,14 @@ pub enum PatternKind {
         #[serde(default, skip_serializing_if = "Option::is_none")]
         #[walk(length = "Spacing 2")]
         spacing2: Option<Expr>,
+        #[serde(default, skip_serializing_if = "default_pattern_alignment")]
+        alignment: solidcraft_sketch::PatternAlignment,
+        #[serde(default, skip_serializing_if = "default_pattern_alignment")]
+        alignment2: solidcraft_sketch::PatternAlignment,
+        #[serde(default, skip_serializing_if = "std::ops::Not::not")]
+        reversed: bool,
+        #[serde(default, skip_serializing_if = "std::ops::Not::not")]
+        reversed2: bool,
     },
     Circular {
         origin: Position,
@@ -1730,6 +1738,10 @@ pub enum PatternKind {
         /// Total angle (360 deg = evenly around).
         #[walk(angle = "Total angle")]
         angle: Expr,
+        #[serde(default, skip_serializing_if = "default_pattern_alignment")]
+        alignment: solidcraft_sketch::PatternAlignment,
+        #[serde(default, skip_serializing_if = "std::ops::Not::not")]
+        reversed: bool,
     },
     /// Copies along a chain of sketch curves: instance k moves by path(k·spacing) − path(0),
     /// measured along the path from its start.
@@ -1753,6 +1765,10 @@ pub enum PatternKind {
     },
 }
 
+fn default_pattern_alignment(alignment: &solidcraft_sketch::PatternAlignment) -> bool {
+    *alignment == solidcraft_sketch::PatternAlignment::Right
+}
+
 fn z_axis() -> Dir {
     Dir(Vec3::Z)
 }

crates/doc/src/eval.rs

@@ -3561,7 +3561,7 @@ fn pattern_transforms(doc: &Document, vals: &BTreeMap<String, Value>, st: &Model
     };
     let mut out = Vec::new();
     match p {
-        crate::PatternKind::Rectangular { dir1, count1, spacing1, dir2, count2, spacing2 } => {
+        crate::PatternKind::Rectangular { dir1, count1, spacing1, dir2, count2, spacing2, alignment, alignment2, reversed, reversed2 } => {
             let (n1, s1) = (count(count1)?, val(vals, spacing1, Kind::Length)?);
             let d1 = dir1.normalized().ok_or_else(|| DocError::Invalid("pattern direction".into()))?;
             let (n2, s2, d2) = match (dir2, count2, spacing2) {
@@ -3578,7 +3578,7 @@ fn pattern_transforms(doc: &Document, vals: &BTreeMap<String, Value>, st: &Model
                     if i == 0 && j == 0 {
                         continue;
                     }
-                    out.push(translation(d1 * (s1 * i as f64) + d2 * (s2 * j as f64)));
+                    out.push(translation(d1 * (s1 * alignment.multiplier(i, *reversed)) + d2 * (s2 * alignment2.multiplier(j, *reversed2))));
                 }
             }
         }
@@ -3615,7 +3615,7 @@ fn pattern_transforms(doc: &Document, vals: &BTreeMap<String, Value>, st: &Model
                 out.push(m);
             }
         }
-        crate::PatternKind::Circular { origin, axis, count: c, angle } => {
+        crate::PatternKind::Circular { origin, axis, count: c, angle, alignment, reversed } => {
             let n = count(c)?;
             let total = val(vals, angle, Kind::Angle)?;
             let full = (total.abs() - std::f64::consts::TAU).abs() < 1e-9;
@@ -3627,7 +3627,7 @@ fn pattern_transforms(doc: &Document, vals: &BTreeMap<String, Value>, st: &Model
                 0.0
             };
             for i in 1..n {
-                out.push(rotation(origin.0, axis.0, step * i as f64));
+                out.push(rotation(origin.0, axis.0, step * alignment.multiplier(i, *reversed)));
             }
         }
     }

crates/doc/src/format/pending/feature-pattern-alignment.rs

@@ -0,0 +1,4 @@
+//! Rectangular and circular feature patterns store alignment and reversal, independently for
+//! each rectangular direction. Defaults preserve older positive-direction placements.
+//! Center retains the source and alternates copies on either side, as sketch patterns do.
+//! The last release refuses this pending format and asks for an update instead of losing it.

crates/doc/src/walk.rs

@@ -42,6 +42,7 @@ impl Walk for i8 {}
 impl Walk for f64 {}
 impl Walk for ProfileSel {}
 impl Walk for solidcraft_sketch::Sketch {}
+impl Walk for solidcraft_sketch::PatternAlignment {}
 impl Walk for solidcraft_kernel::StepNode {}
 impl Walk for crate::document::Operation {}
 impl Walk for solidcraft_kernel::Continuity {}