From 200f10fd25df35576bccfa0768b8a3179e0a3fd1 Mon Sep 17 00:00:00 2001
From: Hakan Seven <hakanseven8125@gmail.com>
Date: Tue, 12 May 2026 22:04:12 +0300
Subject: [PATCH] fix(explode): correct arc/ellipse direction in mirrored
 INSERT blocks
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Mirrored INSERTs reverse OCS handedness, but acadrust's explode used to
keep the original normal — making CCW-around-normal arcs and ellipses
sweep the wrong way. The fix lives in acadrust 7c711e9, which flips the
new normal when det < 0 and reprojects center/major_axis/angles into the
new OCS. H7CAD's fix_mirrored_arc workaround is no longer needed.
---
 Cargo.lock                         |  2 +-
 Cargo.toml                         |  2 +-
 src/modules/home/modify/explode.rs | 29 +++++------------------------
 src/scene/mod.rs                   |  2 --
 4 files changed, 7 insertions(+), 28 deletions(-)

diff --git a/Cargo.lock b/Cargo.lock
index 448c75dac..b5e893e0a 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -41,7 +41,7 @@ checksum = "366ffbaa4442f4684d91e2cd7c5ea7c4ed8add41959a31447066e279e432b618"
 [[package]]
 name = "acadrust"
 version = "0.3.4"
-source = "git+https://github.com/hakanaktt/acadrust#4025fd212880dfaa9bcb8b0a52b0bc2b3d2d4415"
+source = "git+https://github.com/HakanSeven12/acadrust?rev=7c711e9#7c711e9d4bb8fd7e21ea449e335cee9da24d37de"
 dependencies = [
  "ahash",
  "anyhow",
diff --git a/Cargo.toml b/Cargo.toml
index f8a64291f..797b2c154 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -23,4 +23,4 @@ rayon = "1"
 windows-sys = { version = "0.59", features = ["Win32_UI_Shell", "Win32_UI_WindowsAndMessaging"] }
 
 [patch.crates-io]
-acadrust = { git = "https://github.com/hakanaktt/acadrust" }
+acadrust = { git = "https://github.com/HakanSeven12/acadrust", rev = "7c711e9" }
diff --git a/src/modules/home/modify/explode.rs b/src/modules/home/modify/explode.rs
index 112767766..230bbd22c 100644
--- a/src/modules/home/modify/explode.rs
+++ b/src/modules/home/modify/explode.rs
@@ -49,14 +49,11 @@ pub fn explode_entity(entity: &EntityType, document: &CadDocument) -> Vec<Entity
         EntityType::Polyline2D(p) => explode_polyline2d(p),
         EntityType::Polyline(p) => explode_polyline(p),
         EntityType::Polyline3D(p) => explode_polyline3d(p),
-        EntityType::Insert(ins) => {
-            let is_mirrored = ins.x_scale() * ins.y_scale() < 0.0;
-            ins.explode_from_document(document)
-                .into_iter()
-                .map(normalize_insert_entity)
-                .map(|sub| fix_mirrored_arc(sub, is_mirrored))
-                .collect()
-        }
+        EntityType::Insert(ins) => ins
+            .explode_from_document(document)
+            .into_iter()
+            .map(normalize_insert_entity)
+            .collect(),
         EntityType::MLine(ml) => explode_mline(ml),
         EntityType::Dimension(dim) => explode_dimension(dim),
         _ => vec![],
@@ -173,22 +170,6 @@ pub fn normalize_entity_for_block(entity: EntityType) -> EntityType {
     entity
 }
 
-/// Swap arc start/end angles when the INSERT that produced the entity was
-/// mirrored (exactly one of x_scale / y_scale is negative).  The acadrust
-/// explode recalculates endpoint positions correctly but does not reverse the
-/// sweep direction, so the arc would otherwise curve the wrong way.
-pub fn fix_mirrored_arc(entity: EntityType, is_mirrored: bool) -> EntityType {
-    if !is_mirrored {
-        return entity;
-    }
-    if let EntityType::Arc(mut arc) = entity {
-        std::mem::swap(&mut arc.start_angle, &mut arc.end_angle);
-        EntityType::Arc(arc)
-    } else {
-        entity
-    }
-}
-
 fn explode_lwpolyline(p: &LwPolyline) -> Vec<EntityType> {
     let n = p.vertices.len();
     if n < 2 {
diff --git a/src/scene/mod.rs b/src/scene/mod.rs
index 5e9147fb1..d70310f4a 100644
--- a/src/scene/mod.rs
+++ b/src/scene/mod.rs
@@ -3788,7 +3788,6 @@ fn tessellate_entity(
     }
 
     if let EntityType::Insert(ins) = e {
-        let is_mirrored = ins.x_scale() * ins.y_scale() < 0.0;
         // Resolve the INSERT's own style so ByBlock sub-entities can inherit it.
         let (ins_color, ins_pat_len, ins_pat, ins_lw_px, _) = render::render_style_for(document, e);
         let ins_color = render::adapt_to_bg(ins_color, bg_color);
@@ -3797,7 +3796,6 @@ fn tessellate_entity(
             .iter()
             .cloned()
             .map(crate::modules::home::modify::explode::normalize_insert_entity)
-            .map(|sub| crate::modules::home::modify::explode::fix_mirrored_arc(sub, is_mirrored))
             .flat_map(|sub| {
                 let (sub_color, sub_pattern_length, sub_pattern, sub_line_weight_px, sub_aci) =
                     render::render_style_for_block_sub(