diff --git a/source/GM-TE/GMTEBrush.class.st b/source/GM-TE/GMTEBrush.class.st
index a97ea5c2..616c22cb 100644
--- a/source/GM-TE/GMTEBrush.class.st
+++ b/source/GM-TE/GMTEBrush.class.st
@@ -1,3 +1,6 @@
+"
+A GMTEBrush is responsible for returning a set of indices that are selected by the user and selecting the interchangeable algorithm for the execution.
+"
 Class {
 	#name : #GMTEBrush,
 	#superclass : #Object,
@@ -9,7 +12,8 @@ Class {
 		'firstMatrixIndex',
 		'outputSet'
 	],
-	#category : #'GM-TE-UI'
+	#category : #'GM-TE-UI',
+	#'squeak_changestamp' : 'Valentin Teutschbein 7/12/2024 13:49'
 }
 
 {
@@ -22,57 +26,61 @@ GMTEBrush class >> borderingOffsets [
 ]
 
 {
-	#category : #forms,
-	#'squeak_changestamp' : 'JS 7/11/2024 15:40'
+	#category : #brushHelper,
+	#'squeak_changestamp' : 'Valentin Teutschbein 7/12/2024 14:03'
 }
 GMTEBrush >> calculateOffsetsForRadius: aRadius [
     	
 	|offsets|
 	offsets := OrderedCollection new.
-    	(0-radius to: radius) do: [:dx |
-        	(0-radius to: radius) do: [:dy |
+    	(0-self radius to: self radius) do: [:dx |
+        	(0-self radius to: self radius) do: [:dy |
             	((dx squared + dy squared) <= aRadius squared) ifTrue: [offsets add: dx @ dy]]].
 
-	^offsets
+	^ offsets
 ]
 
 {
 	#category : #accessing,
-	#'squeak_changestamp' : 'Valentin Teutschbein 7/6/2024 12:48'
+	#'squeak_changestamp' : 'Valentin Teutschbein 7/12/2024 13:40'
 }
 GMTEBrush >> currentBrush [
+
 	^ currentBrush
 ]
 
 {
 	#category : #accessing,
-	#'squeak_changestamp' : 'Valentin Teutschbein 7/6/2024 12:48'
+	#'squeak_changestamp' : 'Valentin Teutschbein 7/12/2024 13:40'
 }
-GMTEBrush >> currentBrush: anObject [
-	currentBrush := anObject
+GMTEBrush >> currentBrush: aBrush [
+
+	currentBrush := aBrush
 ]
 
 {
 	#category : #accessing,
-	#'squeak_changestamp' : 'Valentin Teutschbein 7/9/2024 08:47'
+	#'squeak_changestamp' : 'Valentin Teutschbein 7/12/2024 13:41'
 }
 GMTEBrush >> currentMatrixIndex [
+
 	^ currentMatrixIndex
 ]
 
 {
 	#category : #accessing,
-	#'squeak_changestamp' : 'Valentin Teutschbein 7/9/2024 08:47'
+	#'squeak_changestamp' : 'Valentin Teutschbein 7/12/2024 13:41'
 }
-GMTEBrush >> currentMatrixIndex: anObject [
-	currentMatrixIndex := anObject
+GMTEBrush >> currentMatrixIndex: anIndex [
+
+	currentMatrixIndex := anIndex
 ]
 
 {
-	#category : #'as yet unclassified',
-	#'squeak_changestamp' : 'Valentin Teutschbein 7/11/2024 17:10'
+	#category : #execute,
+	#'squeak_changestamp' : 'JS 7/12/2024 16:50'
 }
-GMTEBrush >> executeWithMatrixIndex: anIndex andLayer: aLayer [
+GMTEBrush >> executeWithIndex: anIndex andLayer: aLayer [
 
 	anIndex ifNil: [^ nil].
 	self currentMatrixIndex: anIndex.
@@ -81,8 +89,8 @@ GMTEBrush >> executeWithMatrixIndex: anIndex andLayer: aLayer [
 ]
 
 {
-	#category : #forms,
-	#'squeak_changestamp' : 'Valentin Teutschbein 7/11/2024 17:10'
+	#category : #brushes,
+	#'squeak_changestamp' : 'Valentin Teutschbein 7/12/2024 13:26'
 }
 GMTEBrush >> fillBrush [
 
@@ -95,51 +103,49 @@ GMTEBrush >> fillBrush [
 	self outputSet add: self currentMatrixIndex.
 	visited at: self currentMatrixIndex y at: self currentMatrixIndex x put: true.
 	
-	self fillDfsWithVisited: visited andIndex: self currentMatrixIndex andOriginTile: startTile andSet: self outputSet.
+	self fillDfsWithVisited: visited andIndex: self currentMatrixIndex andOriginTile: startTile.
 
     ^ self outputSet
 ]
 
 {
-	#category : #forms,
-	#'squeak_changestamp' : 'JS 7/11/2024 18:28'
+	#category : #brushHelper,
+	#'squeak_changestamp' : 'Valentin Teutschbein 7/12/2024 13:32'
 }
-GMTEBrush >> fillDfsWithVisited: aVisitedMatrix andIndex: anIndex andOriginTile: anOriginTile andSet: aSet [
-	self flag: 'REFACTOR!'.
-	
+GMTEBrush >> fillDfsWithVisited: aVisitedMatrix andIndex: anIndex andOriginTile: anOriginTile [
+
+	| newIndex newTile |
 	GMTEBrush borderingOffsets do: [:offset |
-		| newIndex newTile tilesNil tilesSame |
 		newIndex := offset + anIndex.
 		((self layer inBounds: newIndex) and: [(aVisitedMatrix at: newIndex y at: newIndex x) isNil]) ifTrue:[
 			newTile := self layer at: newIndex y at: newIndex x.
 			
-			tilesNil := (anOriginTile isNil) and: [newTile isNil].
-			tilesSame := (anOriginTile isNil not and: [newTile isNil not]) and: [anOriginTile imageForm bits hash = newTile imageForm bits hash].
-			
-			(tilesNil or: tilesSame) ifTrue: [
-					aSet add: newIndex.
+			(self tile: anOriginTile equalsTile: newTile) ifTrue: [
+					self outputSet add: newIndex.
 					aVisitedMatrix at: newIndex y at: newIndex x put: true.
-					self fillDfsWithVisited: aVisitedMatrix andIndex: newIndex andOriginTile: anOriginTile andSet: aSet]]]
+					self fillDfsWithVisited: aVisitedMatrix andIndex: newIndex andOriginTile: anOriginTile]]]
 ]
 
 {
 	#category : #accessing,
-	#'squeak_changestamp' : 'Valentin Teutschbein 7/9/2024 08:49'
+	#'squeak_changestamp' : 'Valentin Teutschbein 7/12/2024 13:41'
 }
 GMTEBrush >> firstMatrixIndex [
+
 	^ firstMatrixIndex
 ]
 
 {
 	#category : #accessing,
-	#'squeak_changestamp' : 'Valentin Teutschbein 7/9/2024 08:49'
+	#'squeak_changestamp' : 'Valentin Teutschbein 7/12/2024 13:42'
 }
-GMTEBrush >> firstMatrixIndex: anObject [
-	firstMatrixIndex := anObject
+GMTEBrush >> firstMatrixIndex: anIndex [
+
+	firstMatrixIndex := anIndex
 ]
 
 {
-	#category : #forms,
+	#category : #initialization,
 	#'squeak_changestamp' : 'JS 7/11/2024 13:59'
 }
 GMTEBrush >> initialize [
@@ -150,34 +156,36 @@ GMTEBrush >> initialize [
 
 {
 	#category : #accessing,
-	#'squeak_changestamp' : 'Valentin Teutschbein 7/6/2024 14:51'
+	#'squeak_changestamp' : 'Valentin Teutschbein 7/12/2024 13:42'
 }
 GMTEBrush >> layer [
+
 	^ layer
 ]
 
 {
 	#category : #accessing,
-	#'squeak_changestamp' : 'Valentin Teutschbein 7/6/2024 14:51'
+	#'squeak_changestamp' : 'Valentin Teutschbein 7/12/2024 13:42'
 }
-GMTEBrush >> layer: anObject [
-	layer := anObject
+GMTEBrush >> layer: aLayer [
+
+	layer := aLayer
 ]
 
 {
-	#category : #forms,
-	#'squeak_changestamp' : 'Valentin Teutschbein 7/11/2024 17:11'
+	#category : #brushes,
+	#'squeak_changestamp' : 'Valentin Teutschbein 7/12/2024 13:53'
 }
 GMTEBrush >> lineBrush [
 
 	self resetOutputSet.
-	self firstMatrixIndex ifNil: [^nil].
+	self firstMatrixIndex ifNil: [^ nil].
 
-	(self rasterizeLineBetweenAStart: self firstMatrixIndex andAnEnd: self currentMatrixIndex) do: [:point |
+	(self rasterizeLineBetweenStart: self firstMatrixIndex andEnd: self currentMatrixIndex) do: [:index |
 		(self calculateOffsetsForRadius: self offsetCorrectedRadius) do: [:offset | 
-			self outputSet add: (point + offset)]].
+			self outputSet add: (index + offset)]].
 
-	^(self outputSet)
+	^ self outputSet
 
 ]
 
@@ -193,18 +201,20 @@ GMTEBrush >> offsetCorrectedRadius [
 
 {
 	#category : #accessing,
-	#'squeak_changestamp' : 'Valentin Teutschbein 7/9/2024 21:18'
+	#'squeak_changestamp' : 'Valentin Teutschbein 7/12/2024 13:43'
 }
 GMTEBrush >> outputSet [
+
 	^ outputSet
 ]
 
 {
 	#category : #accessing,
-	#'squeak_changestamp' : 'Valentin Teutschbein 7/9/2024 21:18'
+	#'squeak_changestamp' : 'Valentin Teutschbein 7/12/2024 13:43'
 }
-GMTEBrush >> outputSet: anObject [
-	outputSet := anObject
+GMTEBrush >> outputSet: aSet [
+
+	outputSet := aSet
 ]
 
 {
@@ -218,15 +228,15 @@ GMTEBrush >> radius [
 
 {
 	#category : #accessing,
-	#'squeak_changestamp' : 'Valentin Teutschbein 7/11/2024 17:15'
+	#'squeak_changestamp' : 'Valentin Teutschbein 7/12/2024 13:43'
 }
-GMTEBrush >> radius: aNumber [
+GMTEBrush >> radius: aRadius [
 
-	radius := aNumber
+	radius := aRadius
 ]
 
 {
-	#category : #forms,
+	#category : #brushes,
 	#'squeak_changestamp' : 'Valentin Teutschbein 7/11/2024 17:09'
 }
 GMTEBrush >> radiusBrush [
@@ -239,62 +249,64 @@ GMTEBrush >> radiusBrush [
 ]
 
 {
-	#category : #forms,
-	#'squeak_changestamp' : 'JS 7/11/2024 18:26'
+	#category : #brushHelper,
+	#'squeak_changestamp' : 'Valentin Teutschbein 7/12/2024 13:52'
 }
-GMTEBrush >> rasterizeLineBetweenAStart: aStartPoint andAnEnd: anEndPoint [
+GMTEBrush >> rasterizeLineBetweenStart: aStartIndex andEnd: anEndIndex [
 	"implementation of Bresenhams Line Algorithm"
 	
-	| linePointsCollection deltaX deltaY stepX stepY error error2 x y |
+	| lineIndexCollection deltaX deltaY stepX stepY error error2 x y index |
 	
-	self flag: 'todo: method extraction? - Ich glaube geht schlecht'.
+	self flag: 'repeat formatting'.
 	
-    	deltaX := (anEndPoint x - aStartPoint x) abs.
-    	deltaY := (anEndPoint y - aStartPoint y) abs.
-    	stepX := (aStartPoint x < anEndPoint x) ifTrue: [1] ifFalse: [-1].
-    	stepY := (aStartPoint y < anEndPoint y) ifTrue: [1] ifFalse: [-1].
+    	deltaX := (anEndIndex x - aStartIndex x) abs.
+    	deltaY := (anEndIndex y - aStartIndex y) abs.
+    	stepX := (aStartIndex x < anEndIndex x) ifTrue: [1] ifFalse: [-1].
+    	stepY := (aStartIndex y < anEndIndex y) ifTrue: [1] ifFalse: [-1].
     	error := deltaX - deltaY.
-    	x := aStartPoint x.
-    	y := aStartPoint y.
+    	x := aStartIndex x.
+    	y := aStartIndex y.
 
-    	linePointsCollection := OrderedCollection new.
+    	lineIndexCollection := OrderedCollection new.
 
-    	[
-        	| point |
-        	point := x @ y.
-		linePointsCollection add: point.
-        	(x = anEndPoint x and: [y = anEndPoint y]) ifTrue: [
-			^linePointsCollection].
+    	[	index := x @ y.
+		lineIndexCollection add: index.
+        	(x = anEndIndex x and: [y = anEndIndex y]) ifTrue: [^ lineIndexCollection].
         	error2 := 2 * error.
         	(error2 > (0 - deltaY)) ifTrue: [
             	error := error - deltaY.
             	x := x + stepX].
         	(error2 < deltaX) ifTrue: [
             	error := error + deltaX.
-            	y := y + stepY]
-    	] repeat
+            	y := y + stepY]] repeat
 
 ]
 
 {
-	#category : #forms,
-	#'squeak_changestamp' : 'JS 7/11/2024 17:34'
+	#category : #brushes,
+	#'squeak_changestamp' : 'Valentin Teutschbein 7/12/2024 13:57'
 }
 GMTEBrush >> rectangleBrush [
 
+	| endCol endRow startCol startRow |
 	self resetOutputSet.
     	self firstMatrixIndex ifNil: [^ nil].
 
-    	(self currentMatrixIndex x min: self firstMatrixIndex x) to: (self currentMatrixIndex x max: self firstMatrixIndex x) do: [:row |
-        	(self currentMatrixIndex y min: self firstMatrixIndex y) to: (self currentMatrixIndex y max: self firstMatrixIndex y) do: [:col | 
-			self outputSet add: (row @ col)]].
+	startRow := (self currentMatrixIndex x min: self firstMatrixIndex x).
+	endRow := (self currentMatrixIndex x max: self firstMatrixIndex x).
+	startCol := (self currentMatrixIndex y min: self firstMatrixIndex y).
+	endCol := (self currentMatrixIndex y max: self firstMatrixIndex y).
+
+	startRow to: endRow do: [:row |
+ 		startCol to: endCol do: [:col |
+			self outputSet add: (row@col)]].
 
     ^ self outputSet
 
 ]
 
 {
-	#category : #select,
+	#category : #brushHelper,
 	#'squeak_changestamp' : 'JS 7/11/2024 13:43'
 }
 GMTEBrush >> resetOutputSet [
@@ -337,3 +349,16 @@ GMTEBrush >> selectRectangleBrush [
 
 	self currentBrush: [self rectangleBrush]
 ]
+
+{
+	#category : #brushHelper,
+	#'squeak_changestamp' : 'Valentin Teutschbein 7/12/2024 13:31'
+}
+GMTEBrush >> tile: aTile equalsTile: anotherTile [
+	
+	| tilesNil tilesSame |
+	tilesNil := (aTile isNil) and: [anotherTile isNil].
+	tilesSame := (aTile isNil not and: [anotherTile isNil not]) and: [aTile imageForm bits hash = anotherTile imageForm bits hash].
+	
+	^ (tilesNil or: [tilesSame])
+]
diff --git a/source/GM-TE/GMTEEditTilesCommand.class.st b/source/GM-TE/GMTEEditTilesCommand.class.st
index 1972bc86..3d5d2879 100644
--- a/source/GM-TE/GMTEEditTilesCommand.class.st
+++ b/source/GM-TE/GMTEEditTilesCommand.class.st
@@ -2,6 +2,7 @@ Class {
 	#name : #GMTEEditTilesCommand,
 	#superclass : #GMTECommand,
 	#instVars : [
+		'editor',
 		'tileMap',
 		'previousSprites',
 		'currentSprites'
@@ -47,6 +48,22 @@ GMTEEditTilesCommand >> do [
 	self placeTilesFromList: self currentSprites
 ]
 
+{
+	#category : #accessing,
+	#'squeak_changestamp' : 'Alex M 7/12/2024 17:12'
+}
+GMTEEditTilesCommand >> editor [
+	^ editor
+]
+
+{
+	#category : #accessing,
+	#'squeak_changestamp' : 'Alex M 7/12/2024 17:12'
+}
+GMTEEditTilesCommand >> editor: anObject [
+	editor := anObject
+]
+
 {
 	#category : #initialization,
 	#'squeak_changestamp' : 'Alex M 6/28/2024 02:45'
diff --git a/source/GM-TE/GMTEEditor.class.st b/source/GM-TE/GMTEEditor.class.st
index 877965ac..fedd96b3 100644
--- a/source/GM-TE/GMTEEditor.class.st
+++ b/source/GM-TE/GMTEEditor.class.st
@@ -1061,7 +1061,7 @@ GMTEEditor >> exportMenu [
 
 {
 	#category : #'input handling',
-	#'squeak_changestamp' : 'mcjj 7/11/2024 15:57'
+	#'squeak_changestamp' : 'mcjj 7/12/2024 00:19'
 }
 GMTEEditor >> filterEvent: aKeyboardEvent for: anObject [
 	| key |
@@ -1069,22 +1069,15 @@ GMTEEditor >> filterEvent: aKeyboardEvent for: anObject [
 	aKeyboardEvent isKeystroke
 		ifFalse: [^ aKeyboardEvent].
 	
-	key := aKeyboardEvent key.
-	
+	key := aKeyboardEvent keyCharacter.
+
 	aKeyboardEvent commandKeyPressed ifTrue: [
-		aKeyboardEvent shiftPressed
-			ifTrue: [
-				key caseOf: {
-					[$Z] -> [self redo].
-				} otherwise: [^ aKeyboardEvent "no hit"].
-				^ aKeyboardEvent ignore "hit"]
-			ifFalse: [
-				key caseOf: {
-					[$Z] -> [self undo].
-					[$Y] -> [self redo].
-					[$R] -> [self rotateSelectedTile].
-				} otherwise: [^ aKeyboardEvent "no hit"].
-				^ aKeyboardEvent ignore "hit"]].
+		key caseOf: {
+			[$z] -> [self undo].
+			[$y] -> [self redo].
+			[$r] -> [self rotateSelectedTile].
+		} otherwise: [^ aKeyboardEvent "no hit"].
+		^ aKeyboardEvent ignore "hit"].
 	
 	^ aKeyboardEvent "no hit"
 ]
@@ -1791,12 +1784,14 @@ GMTEEditor >> resetSelectedLayers [
 
 {
 	#category : #TODO,
-	#'squeak_changestamp' : 'Alex M 6/25/2024 18:26'
+	#'squeak_changestamp' : 'mcjj 7/11/2024 17:52'
 }
 GMTEEditor >> rotateSelectedTile [
 	
 	self selectedTile: (self selectedTile rotateBy: #right centerAt: (self selectedTile extent / 2)).
-	self tileMap tileSelectionSet highlightImage: self selectedTile
+	self tileMap tileSelectionSet removeAllHighlightings.
+	self tileMap tileSelectionSet highlightImage: self selectedTile.
+	self tileMap tileSelectionSet applyAllHighlightings
 ]
 
 {
diff --git a/source/GM-TE/GMTEEditorTileMap.class.st b/source/GM-TE/GMTEEditorTileMap.class.st
index e5d34777..33e3a0a6 100644
--- a/source/GM-TE/GMTEEditorTileMap.class.st
+++ b/source/GM-TE/GMTEEditorTileMap.class.st
@@ -1,3 +1,6 @@
+"
+A GMTEEditorTileMap is a Tilemap that can only be found in the editor or as an exported .morph file. It provides the additional methods for i/o compared to the regular tilemap.
+"
 Class {
 	#name : #GMTEEditorTileMap,
 	#superclass : #GMTETileMap,
@@ -7,7 +10,8 @@ Class {
 		'previousTileStates',
 		'currentTileChanges'
 	],
-	#category : #'GM-TE-TileMap'
+	#category : #'GM-TE-TileMap',
+	#'squeak_changestamp' : 'JS 7/12/2024 17:04'
 }
 
 {
@@ -23,43 +27,49 @@ GMTEEditorTileMap class >> tileWidth: aWidth tileHeight: aHeight padding: aPaddi
 ]
 
 {
-	#category : #TODO,
-	#'squeak_changestamp' : 'Valentin Teutschbein 7/5/2024 17:07'
+	#category : #accessing,
+	#'squeak_changestamp' : 'JS 7/12/2024 16:55'
 }
-GMTEEditorTileMap >> calculateTileCollectionFromPosition: aPos andLayer: aLayer [
-
-	| index rawCollection resultCollection |
-	self flag: 'remove method'.
-	index := self tileIndexFromPosition: aPos.
-	index ifNil: [^ nil].
-	rawCollection := OrderedCollection new.
-	resultCollection := OrderedCollection new.
-	self flag: 'Add different algos'.
-	rawCollection add: (self tileMatrixStack layer: aLayer at: index y at: index x).
-	self halt.
-
-	rawCollection add: (self tileMatrixStack layer: aLayer at: index y at: ((index x)+1)).
-	rawCollection do: [:t |
-		t ifNil: [resultCollection add: (self generateTileAtlayer: aLayer x: index x y: index y stack: self tileMatrixStack tileType: GMTETile)].
-		t ifNotNil: [resultCollection add: t]
-	].
-	^ resultCollection
+GMTEEditorTileMap >> brush [
+
+	^ self model brush
 ]
 
 {
 	#category : #accessing,
-	#'squeak_changestamp' : 'Alex M 6/28/2024 19:28'
+	#'squeak_changestamp' : 'Valentin Teutschbein 7/12/2024 14:15'
 }
 GMTEEditorTileMap >> currentTileChanges [
+
 	^ currentTileChanges
 ]
 
 {
 	#category : #accessing,
-	#'squeak_changestamp' : 'Alex M 6/28/2024 19:28'
+	#'squeak_changestamp' : 'Valentin Teutschbein 7/12/2024 14:18'
 }
-GMTEEditorTileMap >> currentTileChanges: anObject [
-	currentTileChanges := anObject
+GMTEEditorTileMap >> currentTileChanges: aTileDictionary [
+
+	currentTileChanges := aTileDictionary
+]
+
+{
+	#category : #updating,
+	#'squeak_changestamp' : 'Alex M 7/12/2024 17:16'
+}
+GMTEEditorTileMap >> deleteTiles: anIndexSet inLayer: aLayer [
+	"delete tiles from editable matrix stack at given indices"
+	
+	| tile |
+	anIndexSet do: [:c |
+		((self tileMatrixStack layer: aLayer) inBounds: c) ifTrue: [
+			tile := self tileMatrixStack layer: aLayer at: c y at: c x.
+			tile	ifNotNil: [ 
+				self savePreviousImageFromIndex: c inLayer: aLayer.
+				tile abandon.
+				self tileMatrixStack layer: aLayer at: c y at: c x put: nil.
+				self saveNewImageFromIndex: c inLayer: aLayer.
+				self model savedSinceModified: false]]]
 ]
 
 {
@@ -89,6 +99,22 @@ GMTEEditorTileMap >> handlesMouseOver: anEvent [
 	^ true
 ]
 
+{
+	#category : #updating,
+	#'squeak_changestamp' : 'JS 7/12/2024 15:15'
+}
+GMTEEditorTileMap >> highlightTilesFromIndices: anIndexSet [
+	
+	| hoveredHighlightingTile |
+	self tileSelectionSet clearAllHighlightings.
+	anIndexSet ifNil: [^ nil].
+	
+	(anIndexSet select: [:c | 
+		(self tileMatrixStack layer: self model selectedLayers anyOne) inBounds: c]) do: [:t |
+			hoveredHighlightingTile := self highlightingTileFromIndex: t.
+			hoveredHighlightingTile ifNotNil: [self tileSelectionSet highlightTile: hoveredHighlightingTile]]
+]
+
 {
 	#category : #initialization,
 	#'squeak_changestamp' : 'Ivo Zilkenat 7/12/2024 17:04'
@@ -114,100 +140,118 @@ GMTEEditorTileMap >> model [
 
 {
 	#category : #accessing,
-	#'squeak_changestamp' : 'TW 6/22/2024 01:25'
+	#'squeak_changestamp' : 'JS 7/12/2024 16:25'
 }
-GMTEEditorTileMap >> model: anObject [
+GMTEEditorTileMap >> model: aModel [
 
-	model := anObject
+	model := aModel
 ]
 
 {
 	#category : #'event handling',
-	#'squeak_changestamp' : 'JS 7/11/2024 14:13'
+	#'squeak_changestamp' : 'JS 7/12/2024 16:50'
 }
 GMTEEditorTileMap >> mouseDown: anEvent [
-	"Implements placement of tiles"
+	"prepare the brush for next operation on self"
 
 	| selectedIndex |
-	self flag: 'refactor; method extraction for "Add tiles to layer" to minimize redundancy with mouseMove?'.
-	self model singleLayerSelected ifFalse: [^nil].
+	self model singleLayerSelected ifFalse: [^ nil].
+	
 	selectedIndex := self tileIndexFromPosition: anEvent position.
-	self model brush firstMatrixIndex: selectedIndex.
-	self model brush executeWithMatrixIndex: selectedIndex andLayer: (self tileMatrixStack layer: self model selectedLayers anyOne).
-	anEvent yellowButtonPressed ifTrue: [self tileSelectionSet highlightImage: nil].
+	self brush firstMatrixIndex: selectedIndex.
 	
-	^ true
+	self brush executeWithIndex: selectedIndex andLayer: (self tileMatrixStack layer: self selectedLayers anyOne).
+	anEvent yellowButtonPressed ifTrue: [self tileSelectionSet highlightImage: nil]
 ]
 
 {
 	#category : #'event handling',
-	#'squeak_changestamp' : 'Ivo Zilkenat 7/11/2024 17:18'
+	#'squeak_changestamp' : 'JS 7/12/2024 16:27'
 }
 GMTEEditorTileMap >> mouseLeave: anEvent [
-
-	self tileSelectionSet clearAllHighlightings.
 	
-	^ true
+	self tileSelectionSet clearAllHighlightings
 ]
 
 {
 	#category : #'event handling',
-	#'squeak_changestamp' : 'Ivo Zilkenat 7/12/2024 16:52'
+	#'squeak_changestamp' : 'Ivo Zilkenat 7/12/2024 17:20'
 }
 GMTEEditorTileMap >> mouseMove: anEvent [
-	"Implements highlighting of tiles when hovering"
+	"implements highlighting of tiles when hovering"
 
-	| hoveredTileHighlighting activeLayer selectedCoordinates |
+	| activeLayer selectedIndices currentIndex |
 	super mouseMove: anEvent.
 	anEvent shiftPressed ifTrue: [^ nil].	
 
 	self model singleLayerSelected ifFalse: [^ nil].
 	
-	activeLayer := self model selectedLayers anyOne.
-	selectedCoordinates := self model brush executeWithMatrixIndex: (self tileIndexFromPosition: anEvent position) andLayer: (self tileMatrixStack layer: activeLayer).
-	(anEvent redButtonPressed or: [anEvent yellowButtonPressed]) ifFalse: [self model brush resetOutputSet].
-	self tileSelectionSet clearAllHighlightings.
+	activeLayer := self tileMatrixStack layer: self model selectedLayers anyOne.
+	currentIndex := self tileIndexFromPosition: anEvent position.
+	
+	selectedIndices := self brush executeWithIndex: currentIndex andLayer: activeLayer.
 	
-	selectedCoordinates ifNil: [^ nil].
+	(anEvent redButtonPressed or: [anEvent yellowButtonPressed]) ifFalse: [self brush resetOutputSet].
 	
-	(selectedCoordinates select: [:c | 
-		(self tileMatrixStack layer: activeLayer) inBounds: c]) do: [:t |
-			hoveredTileHighlighting := self highlightingTileFromIndex: t.
-			hoveredTileHighlighting ifNotNil: [self tileSelectionSet highlightTile: hoveredTileHighlighting]]
+	self highlightTilesFromIndices: selectedIndices
 ]
 
 {
 	#category : #'event handling',
-	#'squeak_changestamp' : 'mcjj 7/11/2024 16:20'
+	#'squeak_changestamp' : 'JS 7/12/2024 16:28'
 }
 GMTEEditorTileMap >> mouseUp: anEvent [
+	"apply brush operation on tilemap"
+	
+	| selectedIndices |
+	self brush firstMatrixIndex: nil.
+	
+	selectedIndices := self brush outputSet asCollection.
+	
+	self updateTiles: selectedIndices inLayer: self selectedLayers anyOne FromEvent: anEvent.
+	self brush resetOutputSet.
 	
-	| indicesToAdd activeLayer |
-	self model brush firstMatrixIndex: nil.
-	indicesToAdd := self model brush outputSet.
-	activeLayer := self model selectedLayers anyOne.
-	self updateTiles: (indicesToAdd asCollection) inLayer: activeLayer FromEvent: anEvent.
-	self model brush resetOutputSet.
 	(self previousTileStates isEmpty) ifFalse: [self saveTileEditChanges].
-	self tileSelectionSet clearAllHighlightings.
-	self tileSelectionSet highlightImage: (self model selectedTile)
+	self tileSelectionSet 
+		clearAllHighlightings;
+		highlightImage: (self model selectedTile)
 
 ]
 
+{
+	#category : #updating,
+	#'squeak_changestamp' : 'Alex M 7/12/2024 17:15'
+}
+GMTEEditorTileMap >> placeTiles: aCoordinateCollection inLayer: aLayer [
+	"add currently selected tile (model) to editable matrix stack at given indices"
+	
+	| tile |
+	aCoordinateCollection do: [:c |
+		self savePreviousImageFromIndex: c inLayer: aLayer.
+		((self tileMatrixStack layer: aLayer) inBounds: c) ifTrue: [
+				tile := self tileMatrixStack layer: aLayer at: c y at: c x.
+				tile ifNil: [tile := self generateTileAtlayer: aLayer x: c x y: c y stack: tileMatrixStack tileType: GMTETile].
+				self model selectedTile ifNotNil: [tile updateSprite: self model selectedTile].
+				self saveNewImageFromIndex: c inLayer: aLayer.
+				self model savedSinceModified: false]]
+]
+
 {
 	#category : #accessing,
-	#'squeak_changestamp' : 'Alex M 6/28/2024 19:44'
+	#'squeak_changestamp' : 'Valentin Teutschbein 7/12/2024 14:16'
 }
 GMTEEditorTileMap >> previousTileStates [
+
 	^ previousTileStates
 ]
 
 {
 	#category : #accessing,
-	#'squeak_changestamp' : 'Alex M 6/28/2024 19:44'
+	#'squeak_changestamp' : 'Valentin Teutschbein 7/12/2024 14:18'
 }
-GMTEEditorTileMap >> previousTileStates: anObject [
-	previousTileStates := anObject
+GMTEEditorTileMap >> previousTileStates: aTileDictionary [
+
+	previousTileStates := aTileDictionary
 ]
 
 {
@@ -222,12 +266,12 @@ GMTEEditorTileMap >> rescaleMap [
 ]
 
 {
-	#category : #TODO,
-	#'squeak_changestamp' : 'Alex M 7/3/2024 23:50'
+	#category : #updating,
+	#'squeak_changestamp' : 'JS 7/12/2024 16:31'
 }
 GMTEEditorTileMap >> resetLayers: aSet [
-	| layer |
 	
+	| layer |
 	aSet do: [:layerIndex |
 		layer := self tileMatrixStack layer: layerIndex.
 		layer withIndicesDo: [:tile :y :x |
@@ -250,73 +294,52 @@ GMTEEditorTileMap >> resetTileEditChanges [
 
 {
 	#category : #'command processing',
-	#'squeak_changestamp' : 'Alex M 7/6/2024 01:31'
+	#'squeak_changestamp' : 'JS 7/12/2024 16:34'
 }
-GMTEEditorTileMap >> saveNewImageFromCoordinate: aCoordinate inLayer: aLayer [
-	| tile | 
-	
-	tile := self tileMatrixStack layer: aLayer at: aCoordinate y at: aCoordinate x.
+GMTEEditorTileMap >> saveNewImageFromIndex: anIndex inLayer: aLayer [
 	
+	| tile | 
+	tile := self tileMatrixStack layer: aLayer at: anIndex y at: anIndex x.
+
 	tile
-		ifNil: [self currentTileChanges at: {aCoordinate x. aCoordinate y. aLayer} put: nil]
-		ifNotNil: [self currentTileChanges at: {aCoordinate x. aCoordinate y. aLayer} put: tile fullResolutionSprite]
+		ifNil: [self currentTileChanges at: {anIndex x. anIndex y. aLayer} put: nil]
+		ifNotNil: [self currentTileChanges at: {anIndex x. anIndex y. aLayer} put: tile fullResolutionSprite]
 ]
 
 {
 	#category : #'command processing',
-	#'squeak_changestamp' : 'Alex M 7/6/2024 01:34'
+	#'squeak_changestamp' : 'JS 7/12/2024 16:40'
 }
-GMTEEditorTileMap >> saveNewImageFromPosition: aPosition inLayer: aLayer [
-	
-	self saveNewImageFromCoordinate: (self tileIndexFromPosition: aPosition) inLayer: aLayer
-]
+GMTEEditorTileMap >> savePreviousImageFromIndex: anIndex inLayer: aLayer [
 
-{
-	#category : #'command processing',
-	#'squeak_changestamp' : 'Alex M 7/6/2024 01:54'
-}
-GMTEEditorTileMap >> savePreviousImageFromCoordinate: aCoordinate inLayer: aLayer [
-	| tile | 
-	
-	tile := self tileMatrixStack layer: aLayer at: aCoordinate y at: aCoordinate x.
+	| tile | 	
+	tile := self tileMatrixStack layer: aLayer at: anIndex y at: anIndex x.
 	
 	tile
-		ifNil: [self previousTileStates at: {aCoordinate x. aCoordinate y. aLayer} ifAbsentPut: nil]
-		ifNotNil: [self previousTileStates at: {aCoordinate x. aCoordinate y. aLayer} ifAbsentPut: tile fullResolutionSprite]
+		ifNil: [self previousTileStates at: {anIndex x. anIndex y. aLayer} ifAbsentPut: nil]
+		ifNotNil: [self previousTileStates at: {anIndex x. anIndex y. aLayer} ifAbsentPut: tile fullResolutionSprite]
 ]
 
 {
 	#category : #'command processing',
-	#'squeak_changestamp' : 'Valentin Teutschbein 7/6/2024 11:46'
+	#'squeak_changestamp' : 'JS 7/12/2024 16:43'
 }
-GMTEEditorTileMap >> savePreviousImageFromMatrixCoordinate: aCoordinate inLayer: aLayer [
-	| tile |
-	
-	tile := self tileMatrixStack layer: aLayer at: aCoordinate y at: aCoordinate x.
+GMTEEditorTileMap >> saveTileEditChanges [
 	
-	tile
-		ifNil: [self previousTileStates at: {aCoordinate x. aCoordinate y. aLayer} ifAbsentPut: nil]
-		ifNotNil: [self previousTileStates at: {aCoordinate x. aCoordinate y. aLayer} ifAbsentPut: tile fullResolutionSprite]
-]
-
-{
-	#category : #'command processing',
-	#'squeak_changestamp' : 'Valentin Teutschbein 7/6/2024 11:58'
-}
-GMTEEditorTileMap >> savePreviousImageFromPosition: aPosition inLayer: aLayer [
+	| command |
+	command := GMTEEditTilesCommand previousTiles: self previousTileStates currentTiles: self currentTileChanges tilemap: self.
 	
-	self savePreviousImageFromCoordinate: (self tileIndexFromPosition: aPosition) inLayer: aLayer
+	self model addCommand: command.
+	self resetTileEditChanges
 ]
 
 {
-	#category : #'command processing',
-	#'squeak_changestamp' : 'JS 7/11/2024 14:07'
+	#category : #accessing,
+	#'squeak_changestamp' : 'JS 7/12/2024 16:55'
 }
-GMTEEditorTileMap >> saveTileEditChanges [
+GMTEEditorTileMap >> selectedLayers [
 
-	self 
-		model addCommand: (GMTEEditTilesCommand previousTiles: self previousTileStates currentTiles: self currentTileChanges tilemap: self).
-	self resetTileEditChanges.
+	^ self model selectedLayers
 ]
 
 {
@@ -330,58 +353,25 @@ GMTEEditorTileMap >> tileSelectionSet [
 
 {
 	#category : #accessing,
-	#'squeak_changestamp' : 'TW 6/22/2024 01:25'
+	#'squeak_changestamp' : 'Valentin Teutschbein 7/12/2024 14:16'
 }
-GMTEEditorTileMap >> tileSelectionSet: anObject [
+GMTEEditorTileMap >> tileSelectionSet: aSet [
 
-	tileSelectionSet := anObject
+	tileSelectionSet := aSet
 ]
 
 {
 	#category : #updating,
-	#'squeak_changestamp' : 'Alex M 6/25/2024 18:08'
+	#'squeak_changestamp' : 'Alex M 7/12/2024 17:14'
 }
-GMTEEditorTileMap >> updateTileSprite: aTile [
-	"Helper function to apply sprite from tile selection to aTile"
-
-	self model selectedTile ifNotNil: [aTile updateSprite: self model selectedTile]
-]
-
-{
-	#category : #updating,
-	#'squeak_changestamp' : 'Alex M 7/11/2024 17:39'
-}
-GMTEEditorTileMap >> updateTiles: aCoordinateCollection inLayer: aLayer FromEvent: anEvent [
-	"Add currently selected tile (model) to editable matrix stack at mouse position"
-	| tile |
-	self flag: 'refactor'.
+GMTEEditorTileMap >> updateTiles: anIndexSet inLayer: aLayer FromEvent: anEvent [
+	
+	| validLeftClick validRightClick |
 	(self tileIndexFromPosition: anEvent position) ifNil: [^ nil].
-	(anEvent redButtonChanged and: [self model selectedTile notNil]) 
-		ifTrue: [
-			aCoordinateCollection do: [:c |
-				self savePreviousImageFromMatrixCoordinate: c inLayer: aLayer.
-				((self tileMatrixStack layer: aLayer) inBounds: c) ifTrue: [
-					tile := self tileMatrixStack layer: aLayer at: c y at: c x.
-					tile
-						ifNil: [ tile := self generateTileAtlayer: aLayer x: c x y: c y stack: tileMatrixStack tileType: GMTETile].
-					self updateTileSprite: tile.
-					self saveNewImageFromPosition: tile position inLayer: aLayer]
-				].
-			self model savedSinceModified: false].
-	(anEvent yellowButtonChanged) 
-		ifTrue: [
-			aCoordinateCollection do: [:c |
-				| tilePos |
-				((self tileMatrixStack layer: aLayer) inBounds: c) ifTrue: [
-					tile := self tileMatrixStack layer: aLayer at: c y at: c x.
-					tile
-						ifNotNil: [ 
-							self savePreviousImageFromMatrixCoordinate: c inLayer: aLayer.
-							tilePos := tile position.
-							tile abandon.
-							self tileMatrixStack layer: aLayer at: c y at: c x put: nil.
-							self saveNewImageFromPosition: tilePos inLayer: aLayer.
-							self model savedSinceModified: false].
-					]
-				]]
+	
+	validLeftClick := anEvent redButtonChanged and: [self model selectedTile notNil].
+	validRightClick := anEvent yellowButtonChanged.
+	
+	validLeftClick ifTrue: [self placeTiles: anIndexSet inLayer: aLayer].	
+	validRightClick ifTrue: [self deleteTiles: anIndexSet inLayer: aLayer].
 ]
diff --git a/source/GM-TE/GMTETileSelectionSet.class.st b/source/GM-TE/GMTETileSelectionSet.class.st
index 51ad30b8..44228e7d 100644
--- a/source/GM-TE/GMTETileSelectionSet.class.st
+++ b/source/GM-TE/GMTETileSelectionSet.class.st
@@ -7,6 +7,17 @@ Class {
 	#category : #'GM-TE-TileMap'
 }
 
+{
+	#category : #highlighting,
+	#'squeak_changestamp' : 'mcjj 7/11/2024 17:11'
+}
+GMTETileSelectionSet >> applyAllHighlightings [
+	
+	self do: [:tile |
+		self applyHighlightingVisuals: tile]
+	
+]
+
 {
 	#category : #highlighting,
 	#'squeak_changestamp' : 'Ivo Zilkenat 6/24/2024 11:51'
@@ -71,6 +82,17 @@ GMTETileSelectionSet >> initialize: n [
 	
 ]
 
+{
+	#category : #highlighting,
+	#'squeak_changestamp' : 'mcjj 7/11/2024 17:52'
+}
+GMTETileSelectionSet >> removeAllHighlightings [
+	"Remove applied highlightings if any"
+	
+	self do: [:tile |
+		self removeHighlightingVisuals: tile]
+]
+
 {
 	#category : #highlighting,
 	#'squeak_changestamp' : 'Ivo Zilkenat 6/24/2024 11:51'
diff --git a/source/GM-TE/GMTETilemapSizeCommand.class.st b/source/GM-TE/GMTETilemapSizeCommand.class.st
index fe18b4f0..fe683543 100644
--- a/source/GM-TE/GMTETilemapSizeCommand.class.st
+++ b/source/GM-TE/GMTETilemapSizeCommand.class.st
@@ -2,7 +2,6 @@ Class {
 	#name : #GMTETilemapSizeCommand,
 	#superclass : #GMTEEditTilesCommand,
 	#instVars : [
-		'editor',
 		'method',
 		'prevSize',
 		'newSize',
@@ -34,22 +33,6 @@ GMTETilemapSizeCommand >> do [
 	self editor perform: self method with: self newSize
 ]
 
-{
-	#category : #accessing,
-	#'squeak_changestamp' : 'Alex M 7/1/2024 18:00'
-}
-GMTETilemapSizeCommand >> editor [
-	^ editor
-]
-
-{
-	#category : #accessing,
-	#'squeak_changestamp' : 'Alex M 7/1/2024 18:00'
-}
-GMTETilemapSizeCommand >> editor: anObject [
-	editor := anObject
-]
-
 {
 	#category : #accessing,
 	#'squeak_changestamp' : 'Alex M 7/1/2024 18:48'
diff --git a/testMapFile.morph b/testMapFile.morph
index 14d6c90c..3c046b80 100644
Binary files a/testMapFile.morph and b/testMapFile.morph differ