From 39fb51d401b8c76de315dcf3ad363ba7ff00aeec Mon Sep 17 00:00:00 2001
From: Mikolaj Wielgus <wielgusmikolaj@gmail.com>
Date: Mon, 25 May 2026 01:11:29 +0200
Subject: [PATCH] Get rid of layer groups. `LayerDesc`s already do the job

---
 topola/src/board/layer.rs | 25 +------------------------
 topola/src/board/mod.rs   | 12 ++----------
 topola/src/specctra.rs    | 10 +---------
 3 files changed, 4 insertions(+), 43 deletions(-)

diff --git a/topola/src/board/layer.rs b/topola/src/board/layer.rs
index 1ad5e6e..a593b2c 100644
--- a/topola/src/board/layer.rs
+++ b/topola/src/board/layer.rs
@@ -3,33 +3,10 @@
 // SPDX-License-Identifier: MIT OR Apache-2.0
 
 use core::fmt::Display;
-use derive_more::{Constructor, From};
+use derive_more::Constructor;
 use serde::{Deserialize, Serialize};
 use std::fmt::Formatter;
 
-#[derive(
-    Clone,
-    Constructor,
-    Copy,
-    Debug,
-    Default,
-    Deserialize,
-    Eq,
-    From,
-    Ord,
-    PartialEq,
-    PartialOrd,
-    Serialize,
-)]
-pub struct LayerGroupId(usize);
-
-impl LayerGroupId {
-    #[inline]
-    pub fn index(self) -> usize {
-        self.0
-    }
-}
-
 #[derive(Clone, Copy, Debug, Deserialize, Eq, Ord, PartialEq, PartialOrd, Serialize)]
 pub enum LayerType {
     Copper,
diff --git a/topola/src/board/mod.rs b/topola/src/board/mod.rs
index 9254a85..398c1b1 100644
--- a/topola/src/board/mod.rs
+++ b/topola/src/board/mod.rs
@@ -8,7 +8,7 @@ mod select;
 pub mod selections;
 mod transforms;
 
-pub use crate::board::layer::{LayerDesc, LayerGroupId, LayerTier, LayerType};
+pub use crate::board::layer::{LayerDesc, LayerTier, LayerType};
 
 use bidimap::BiBTreeMap;
 use derive_getters::Getters;
@@ -30,8 +30,6 @@ use crate::{
 pub struct Board {
     layout: Layout,
     #[getter(skip)]
-    layer_groups: Recorder<Vec<LayerGroupId>>,
-    #[getter(skip)]
     component_names: Recorder<BiBTreeMap<ComponentId, String>>,
     #[getter(skip)]
     pin_names: Recorder<BiBTreeMap<PinId, String>>,
@@ -54,16 +52,14 @@ impl Board {
 
     pub fn with_names(
         boundary: Vec<Vector2<i64>>,
-        layer_groups: Vec<LayerGroupId>,
         layer_descs: BiBTreeMap<LayerId, LayerDesc>,
         net_names: BiBTreeMap<NetId, String>,
     ) -> Self {
         Self {
             layout: Layout::new(
                 boundary.into_iter().map(Into::into).collect(),
-                layer_groups.len(),
+                layer_descs.len(),
             ),
-            layer_groups: Recorder::new(layer_groups),
             component_names: Recorder::new(BiBTreeMap::new()),
             pin_names: Recorder::new(BiBTreeMap::new()),
             layer_descs: Recorder::new(layer_descs),
@@ -159,10 +155,6 @@ impl Board {
             })
     }
 
-    pub fn layer_group(&self, layer: LayerId) -> LayerGroupId {
-        self.layer_groups[layer.index()]
-    }
-
     pub fn net_name(&self, id: NetId) -> Option<&str> {
         self.net_names.get_by_left(&id).map(String::as_str)
     }
diff --git a/topola/src/specctra.rs b/topola/src/specctra.rs
index 7a4140e..5d9ff11 100644
--- a/topola/src/specctra.rs
+++ b/topola/src/specctra.rs
@@ -11,7 +11,7 @@ use specctra::{
 };
 
 use crate::{
-    board::{Board, LayerDesc, LayerGroupId, LayerTier, LayerType},
+    board::{Board, LayerDesc, LayerTier, LayerType},
     layout::LayerId,
     layout::compounds::{ComponentId, NetId, PinId},
     math::Vector2,
@@ -80,13 +80,6 @@ impl Board {
             BiBTreeMap::from_iter(tmp.into_iter().enumerate().map(|(i, v)| (NetId::new(i), v)))
         };
 
-        let mut layer_groups = vec![LayerGroupId::new(1)];
-        layer_groups.extend(std::iter::repeat_n(
-            LayerGroupId::new(0),
-            dsn.pcb.structure.layers.len(),
-        ));
-        layer_groups.push(LayerGroupId::new(1));
-
         let mut board = Board::with_names(
             dsn.pcb
                 .structure
@@ -103,7 +96,6 @@ impl Board {
                     )
                 })
                 .collect(),
-            layer_groups,
             layer_descs,
             net_names,
         );