DIMRADIUS/DIMDIAMETER: a location outside the circle puts the text at that point (fixes #1170) (#1189)

crates/engine/src/cmd/annotate.rs

@@ -260,18 +260,16 @@ fn radial(s: &mut Session, p: &Value, diameter: bool) -> Result<Value> {
         dim(s, DimKind::Radius, c, Vec2::ZERO, Vec2::ZERO, pt, Vec2::ZERO, "")
     };
     let k = match at {
-        Some(at) => text_inside(k, c, c.dist(pt), at),
+        Some(at) => text_at(k, at),
         None => k,
     };
     Ok(json!({ "handle": add_dim(s, k)?.hex() }))
 }
 
-/// A radius/diameter dimension line location picked inside the circle puts the text there, on
-/// the dimension line (outside, the text keeps its default place beyond the arrowhead).
-fn text_inside(mut k: EntityKind, c: Vec2, r: f64, at: Vec2) -> EntityKind {
-    if let EntityKind::Dimension(d) = &mut k
-        && at.dist(c) < r
-    {
+/// The dimension line location of a radius/diameter dimension puts the text there, inside or
+/// outside the circle, as a user-positioned text (DXF flag 70 bit 128), like AutoCAD.
+fn text_at(mut k: EntityKind, at: Vec2) -> EntityKind {
+    if let EntityKind::Dimension(d) = &mut k {
         d.text_mid = v3(at);
         d.user_text_pos = true;
     }
@@ -1106,7 +1104,7 @@ impl RadialM {
         } else {
             dim(s, DimKind::Radius, c, Vec2::ZERO, Vec2::ZERO, pt, Vec2::ZERO, "")
         });
-        text_inside(k, c, r, at)
+        text_at(k, at)
     }
 }
 

crates/engine/tests/dim_radial_inside.rs

@@ -36,11 +36,10 @@ fn radial_text_goes_inside_when_the_location_is_inside() {
     assert!(covers(&g, 9.0) && !covers(&g, 4.0) && !covers(&g, 1.0));
     assert!(g.lines_of(LineRole::Dim).flatten().all(|p| p.len() <= 10.0 + 1e-9));
 
-    // Outside: the default placement beyond the arrowhead.
+    // Outside: the text goes to the point too (dim_radial_outside.rs), beyond the arrowhead.
     s.script("dimradius 0,10 0,15\n").unwrap();
     assert!(s.running.is_none());
-    let (dm, g) = last_dim(&s);
-    assert!(!dm.user_text_pos);
+    let (_, g) = last_dim(&s);
     assert!(g.text_pos.y > 10.0, "{:?}", g.text_pos);
 
     // JSON form, diameter: the line spans the circle, broken around the text.

crates/engine/tests/dim_radial_outside.rs

@@ -0,0 +1,62 @@
+//! DIMRADIUS / DIMDIAMETER: a dimension line location picked outside the circle puts the text
+//! at that point (group 11, flag 70 bit 128), as for a location inside; the leader stops short
+//! of the text instead of running into it.
+
+use cadcraft_engine::Session;
+use cadcraft_engine::doc::{Dimension, EntityKind};
+use cadcraft_engine::geom::Vec2;
+use cadcraft_engine::render::{DimGeometry, LineRole};
+use serde_json::json;
+
+fn last_dim(s: &Session) -> (Dimension, DimGeometry) {
+    let d = s.doc().unwrap();
+    match &d.model.last().unwrap().kind {
+        EntityKind::Dimension(dm) => (dm.clone(), cadcraft_engine::render::dimension_in(d, dm)),
+        other => panic!("not a dimension: {other:?}"),
+    }
+}
+
+/// Group 70 of every DIMENSION in the saved DXF.
+fn dxf_flags(s: &Session) -> Vec<i64> {
+    let text = cadcraft_io::write_dxf(s.doc().unwrap());
+    let lines: Vec<&str> = text.lines().map(str::trim).collect();
+    let mut flags = Vec::new();
+    let mut in_dim = false;
+    for p in lines.chunks(2) {
+        match p {
+            ["0", v] => in_dim = *v == "DIMENSION",
+            ["70", v] if in_dim => flags.push(v.parse().unwrap()),
+            _ => {}
+        }
+    }
+    flags
+}
+
+fn assert_text_at(s: &Session, at: Vec2) {
+    assert!(s.running.is_none());
+    let (dm, g) = last_dim(s);
+    assert!(dm.user_text_pos);
+    assert!(dm.text_mid.xy().dist(at) < 1e-9, "{:?}", dm.text_mid);
+    assert!(g.text_pos.dist(at) < 1e-9, "{:?}", g.text_pos);
+    let nearest = g.lines_of(LineRole::Dim).flatten().map(|p| p.dist(at)).fold(f64::INFINITY, f64::min);
+    assert!(nearest > 0.05, "the leader runs into the text: {nearest}");
+}
+
+#[test]
+fn radial_text_goes_to_a_location_outside_the_circle() {
+    let mut s = Session::new();
+    s.script("circle 50,50 25\n").unwrap();
+    s.script("dimradius 75,50 100,80\n").unwrap();
+    assert_text_at(&s, Vec2::new(100.0, 80.0));
+
+    s.script("circle 300,50 25\n").unwrap();
+    s.script("dimdiameter 325,50 350,80\n").unwrap();
+    assert_text_at(&s, Vec2::new(350.0, 80.0));
+
+    s.execute("arc", &json!({"center": [50, 200], "radius": 25, "start": 0, "end": 90})).unwrap();
+    s.script("dimradius 75,200 100,230\n").unwrap();
+    assert_text_at(&s, Vec2::new(100.0, 230.0));
+
+    // Radius 4 | 32 | 128, diameter 3 | 32 | 128, as AutoCAD writes them.
+    assert_eq!(dxf_flags(&s), vec![164, 163, 164]);
+}

crates/render/src/dim.rs

@@ -777,7 +777,16 @@ pub fn dimension_geometry_with(d: &Dimension, st: &DimStyle, dimscale: f64, font
                         end(&mut g, blk1, start, -u);
                     }
                 }
-                g.dim(vec![tip, tpos]);
+                // Text the user placed: the leader stops short of it by the offset the default
+                // placement leaves between leader end and text.
+                let lead = if !d.user_text_pos {
+                    tpos
+                } else if horizontal {
+                    text_mid - Vec2::new(tw / 2.0 + gap, 0.0) * if u.x >= 0.0 { 1.0 } else { -1.0 }
+                } else {
+                    text_mid - u * (tw / 2.0 + gap)
+                };
+                g.dim(vec![tip, lead]);
             }
             end(&mut g, blk2, tip, u);
             if horizontal {