fix: improve classic leader behavior and annotation linkage

src/entities/leader.rs

@@ -159,7 +159,59 @@ fn grips(leader: &Leader) -> Vec<GripDef> {
 
 fn apply_grip(leader: &mut Leader, grip_id: usize, apply: GripApply) {
     let n = leader.vertices.len();
+
     if grip_id < n {
+        if n >= 3 && leader.creation_type == LeaderCreationType::WithText {
+            // Grip del codo: mueve el codo libremente, pero arrastra también
+            // el extremo del renglón manteniendo la distancia relativa.
+            if grip_id == n - 2 {
+                let old_elbow = leader.vertices[n - 2];
+                let old_end = leader.vertices[n - 1];
+
+                let delta = match apply {
+                    GripApply::Absolute(p) => acadrust::types::Vector3::new(
+                        p.x as f64 - old_elbow.x,
+                        p.y as f64 - old_elbow.y,
+                        p.z as f64 - old_elbow.z,
+                    ),
+                    GripApply::Translate(d) => acadrust::types::Vector3::new(
+                        d.x as f64,
+                        d.y as f64,
+                        d.z as f64,
+                    ),
+                };
+
+                leader.vertices[n - 2].x = old_elbow.x + delta.x;
+                leader.vertices[n - 2].y = old_elbow.y + delta.y;
+                leader.vertices[n - 2].z = old_elbow.z + delta.z;
+
+                leader.vertices[n - 1].x = old_end.x + delta.x;
+                leader.vertices[n - 1].y = old_end.y + delta.y;
+                leader.vertices[n - 1].z = old_end.z + delta.z;
+
+                return;
+            }
+
+            // Grip del extremo horizontal: sólo debe estirar en X;
+            // Y/Z quedan pegados al codo para que siga horizontal.
+            if grip_id == n - 1 {
+                let elbow = leader.vertices[n - 2];
+
+                match apply {
+                    GripApply::Absolute(p) => {
+                        leader.vertices[n - 1].x = p.x as f64;
+                    }
+                    GripApply::Translate(d) => {
+                        leader.vertices[n - 1].x += d.x as f64;
+                    }
+                }
+
+                leader.vertices[n - 1].y = elbow.y;
+                leader.vertices[n - 1].z = elbow.z;
+                return;
+            }
+        }
+
         if let Some(v) = leader.vertices.get_mut(grip_id) {
             match apply {
                 GripApply::Absolute(p) => {
@@ -176,7 +228,9 @@ fn apply_grip(leader: &mut Leader, grip_id: usize, apply: GripApply) {
         }
     } else if let GripApply::Translate(d) = apply {
         leader.translate(acadrust::types::Vector3::new(
-            d.x as f64, d.y as f64, d.z as f64,
+            d.x as f64,
+            d.y as f64,
+            d.z as f64,
         ));
     }
 }