When a custom brush is selected, it now appears as an indicator at the cursor

Also moved blend_image_with_color() to Global and the custom brush image (resized & blended accordingly with the selected color and interpolation factor) is now updated every time something changes (size, color etc) and not every time you draw. This is not true for the eraser, however, as it must be blended with Color(0, 0, 0, 0)

Main.tscn

@@ -17,13 +17,13 @@ anchor_bottom = 1.0
 script = ExtResource( 1 )
 
 [node name="UI" type="HBoxContainer" parent="."]
+editor/display_folded = true
 anchor_right = 1.0
 anchor_bottom = 1.0
 size_flags_horizontal = 3
 custom_constants/separation = 0
 
 [node name="ToolPanel" type="Panel" parent="UI"]
-editor/display_folded = true
 margin_right = 320.0
 margin_bottom = 600.0
 rect_min_size = Vector2( 320, 0 )
@@ -36,12 +36,12 @@ size_flags_horizontal = 3
 size_flags_vertical = 3
 
 [node name="MenusAndTools" type="VBoxContainer" parent="UI/ToolPanel/Tools"]
-margin_right = 320.0
+margin_right = 328.0
-margin_bottom = 270.0
+margin_bottom = 266.0
 size_flags_vertical = 3
 
 [node name="MenuItems" type="HBoxContainer" parent="UI/ToolPanel/Tools/MenusAndTools"]
-margin_right = 320.0
+margin_right = 328.0
 margin_bottom = 20.0
 
 [node name="FileMenu" type="MenuButton" parent="UI/ToolPanel/Tools/MenusAndTools/MenuItems"]
@@ -78,7 +78,7 @@ text = "Help"
 [node name="ToolsContainer" type="HBoxContainer" parent="UI/ToolPanel/Tools/MenusAndTools"]
 editor/display_folded = true
 margin_top = 24.0
-margin_right = 320.0
+margin_right = 328.0
 margin_bottom = 44.0
 
 [node name="Pencil" type="Button" parent="UI/ToolPanel/Tools/MenusAndTools/ToolsContainer"]
@@ -136,30 +136,29 @@ button_mask = 3
 text = "RectSelect"
 
 [node name="HSeparator" type="HSeparator" parent="UI/ToolPanel/Tools"]
-margin_top = 274.0
+margin_top = 270.0
-margin_right = 320.0
+margin_right = 328.0
-margin_bottom = 278.0
+margin_bottom = 274.0
 
 [node name="ToolOptions" type="HBoxContainer" parent="UI/ToolPanel/Tools"]
-editor/display_folded = true
+margin_top = 278.0
-margin_top = 282.0
+margin_right = 328.0
-margin_right = 320.0
+margin_bottom = 544.0
-margin_bottom = 552.0
 size_flags_vertical = 3
 
 [node name="LeftToolOptions" type="VBoxContainer" parent="UI/ToolPanel/Tools/ToolOptions"]
-margin_right = 154.0
+margin_right = 158.0
-margin_bottom = 270.0
+margin_bottom = 266.0
 size_flags_horizontal = 3
 
 [node name="LeftLabel" type="Label" parent="UI/ToolPanel/Tools/ToolOptions/LeftToolOptions"]
-margin_right = 154.0
+margin_right = 158.0
 margin_bottom = 14.0
 text = "Left tool options"
 
 [node name="LeftIndicatorCheckbox" type="CheckBox" parent="UI/ToolPanel/Tools/ToolOptions/LeftToolOptions"]
 margin_top = 18.0
-margin_right = 154.0
+margin_right = 158.0
 margin_bottom = 42.0
 mouse_default_cursor_shape = 2
 pressed = true
@@ -176,9 +175,8 @@ size_flags_horizontal = 0
 size_flags_vertical = 0
 
 [node name="BrushSize" type="HBoxContainer" parent="UI/ToolPanel/Tools/ToolOptions/LeftToolOptions"]
-editor/display_folded = true
 margin_top = 82.0
-margin_right = 154.0
+margin_right = 158.0
 margin_bottom = 106.0
 
 [node name="BrushSizeLabel" type="Label" parent="UI/ToolPanel/Tools/ToolOptions/LeftToolOptions/BrushSize"]
@@ -198,13 +196,13 @@ suffix = "px"
 
 [node name="ColorComesFrom" type="Label" parent="UI/ToolPanel/Tools/ToolOptions/LeftToolOptions"]
 margin_top = 110.0
-margin_right = 154.0
+margin_right = 158.0
 margin_bottom = 124.0
 text = "Brush's color from"
 
 [node name="InterpolateColor" type="HBoxContainer" parent="UI/ToolPanel/Tools/ToolOptions/LeftToolOptions"]
 margin_top = 128.0
-margin_right = 154.0
+margin_right = 158.0
 margin_bottom = 144.0
 
 [node name="BrushColorLabel" type="Label" parent="UI/ToolPanel/Tools/ToolOptions/LeftToolOptions/InterpolateColor"]
@@ -216,7 +214,7 @@ text = "Brush"
 
 [node name="LeftInterpolateFactor" type="HSlider" parent="UI/ToolPanel/Tools/ToolOptions/LeftToolOptions/InterpolateColor"]
 margin_left = 41.0
-margin_right = 117.0
+margin_right = 121.0
 margin_bottom = 16.0
 size_flags_horizontal = 3
 max_value = 1.0
@@ -225,32 +223,32 @@ value = 0.5
 ticks_on_borders = true
 
 [node name="SelectedColorLabel" type="Label" parent="UI/ToolPanel/Tools/ToolOptions/LeftToolOptions/InterpolateColor"]
-margin_left = 121.0
+margin_left = 125.0
 margin_top = 1.0
-margin_right = 154.0
+margin_right = 158.0
 margin_bottom = 15.0
 rect_pivot_offset = Vector2( -90, -47 )
 text = "Color"
 
 [node name="VSeparator" type="VSeparator" parent="UI/ToolPanel/Tools/ToolOptions"]
-margin_left = 158.0
+margin_left = 162.0
-margin_right = 162.0
+margin_right = 166.0
-margin_bottom = 270.0
+margin_bottom = 266.0
 
 [node name="RightToolOptions" type="VBoxContainer" parent="UI/ToolPanel/Tools/ToolOptions"]
-margin_left = 166.0
+margin_left = 170.0
-margin_right = 320.0
+margin_right = 328.0
-margin_bottom = 270.0
+margin_bottom = 266.0
 size_flags_horizontal = 3
 
 [node name="RightLabel" type="Label" parent="UI/ToolPanel/Tools/ToolOptions/RightToolOptions"]
-margin_right = 154.0
+margin_right = 158.0
 margin_bottom = 14.0
 text = "Right tool options"
 
 [node name="RightIndicatorCheckbox" type="CheckBox" parent="UI/ToolPanel/Tools/ToolOptions/RightToolOptions"]
 margin_top = 18.0
-margin_right = 154.0
+margin_right = 158.0
 margin_bottom = 42.0
 mouse_default_cursor_shape = 2
 text = "Show right indicator"
@@ -267,7 +265,7 @@ size_flags_vertical = 0
 
 [node name="BrushSize" type="HBoxContainer" parent="UI/ToolPanel/Tools/ToolOptions/RightToolOptions"]
 margin_top = 82.0
-margin_right = 154.0
+margin_right = 158.0
 margin_bottom = 106.0
 
 [node name="BrushSizeLabel" type="Label" parent="UI/ToolPanel/Tools/ToolOptions/RightToolOptions/BrushSize"]
@@ -287,13 +285,13 @@ suffix = "px"
 
 [node name="ColorComesFrom" type="Label" parent="UI/ToolPanel/Tools/ToolOptions/RightToolOptions"]
 margin_top = 110.0
-margin_right = 154.0
+margin_right = 158.0
 margin_bottom = 124.0
 text = "Brush's color from"
 
 [node name="InterpolateColor" type="HBoxContainer" parent="UI/ToolPanel/Tools/ToolOptions/RightToolOptions"]
 margin_top = 128.0
-margin_right = 154.0
+margin_right = 158.0
 margin_bottom = 144.0
 
 [node name="BrushColorLabel" type="Label" parent="UI/ToolPanel/Tools/ToolOptions/RightToolOptions/InterpolateColor"]
@@ -305,7 +303,7 @@ text = "Brush"
 
 [node name="RightInterpolateFactor" type="HSlider" parent="UI/ToolPanel/Tools/ToolOptions/RightToolOptions/InterpolateColor"]
 margin_left = 41.0
-margin_right = 117.0
+margin_right = 121.0
 margin_bottom = 16.0
 size_flags_horizontal = 3
 max_value = 1.0
@@ -314,22 +312,23 @@ value = 0.5
 ticks_on_borders = true
 
 [node name="SelectedColorLabel" type="Label" parent="UI/ToolPanel/Tools/ToolOptions/RightToolOptions/InterpolateColor"]
-margin_left = 121.0
+margin_left = 125.0
 margin_top = 1.0
-margin_right = 154.0
+margin_right = 158.0
 margin_bottom = 15.0
 rect_pivot_offset = Vector2( -90, -47 )
 text = "Color"
 
 [node name="HSeparator2" type="HSeparator" parent="UI/ToolPanel/Tools"]
-margin_top = 556.0
+margin_top = 548.0
-margin_right = 320.0
+margin_right = 328.0
-margin_bottom = 560.0
+margin_bottom = 552.0
 
 [node name="BrushesContainer" type="ScrollContainer" parent="UI/ToolPanel/Tools"]
-margin_top = 564.0
+editor/display_folded = true
-margin_right = 320.0
+margin_top = 556.0
-margin_bottom = 600.0
+margin_right = 328.0
+margin_bottom = 592.0
 size_flags_horizontal = 3
 scroll_vertical_enabled = false
 
@@ -339,6 +338,11 @@ margin_bottom = 36.0
 
 [node name="PixelBrushButton" parent="UI/ToolPanel/Tools/BrushesContainer/BrushHBoxContainer" instance=ExtResource( 5 )]
 
+[node name="HSeparator3" type="HSeparator" parent="UI/ToolPanel/Tools"]
+margin_top = 596.0
+margin_right = 328.0
+margin_bottom = 600.0
+
 [node name="CanvasAndTimeline" type="VBoxContainer" parent="UI"]
 margin_left = 320.0
 margin_right = 864.0
@@ -992,13 +996,17 @@ align = 1
 
 [node name="AnimationTimer" type="Timer" parent="."]
 [connection signal="toggled" from="UI/ToolPanel/Tools/ToolOptions/LeftToolOptions/LeftIndicatorCheckbox" to="." method="_on_LeftIndicatorCheckbox_toggled"]
+[connection signal="color_changed" from="UI/ToolPanel/Tools/ToolOptions/LeftToolOptions/LeftColorPickerButton" to="." method="_on_LeftColorPickerButton_color_changed"]
 [connection signal="popup_closed" from="UI/ToolPanel/Tools/ToolOptions/LeftToolOptions/LeftColorPickerButton" to="." method="_can_draw_true"]
 [connection signal="pressed" from="UI/ToolPanel/Tools/ToolOptions/LeftToolOptions/LeftColorPickerButton" to="." method="_can_draw_false"]
 [connection signal="value_changed" from="UI/ToolPanel/Tools/ToolOptions/LeftToolOptions/BrushSize/LeftBrushSizeEdit" to="." method="_on_LeftBrushSizeEdit_value_changed"]
+[connection signal="value_changed" from="UI/ToolPanel/Tools/ToolOptions/LeftToolOptions/InterpolateColor/LeftInterpolateFactor" to="." method="_on_LeftInterpolateFactor_value_changed"]
 [connection signal="toggled" from="UI/ToolPanel/Tools/ToolOptions/RightToolOptions/RightIndicatorCheckbox" to="." method="_on_RightIndicatorCheckbox_toggled"]
+[connection signal="color_changed" from="UI/ToolPanel/Tools/ToolOptions/RightToolOptions/RightColorPickerButton" to="." method="_on_RightColorPickerButton_color_changed"]
 [connection signal="popup_closed" from="UI/ToolPanel/Tools/ToolOptions/RightToolOptions/RightColorPickerButton" to="." method="_can_draw_true"]
 [connection signal="pressed" from="UI/ToolPanel/Tools/ToolOptions/RightToolOptions/RightColorPickerButton" to="." method="_can_draw_false"]
 [connection signal="value_changed" from="UI/ToolPanel/Tools/ToolOptions/RightToolOptions/BrushSize/RightBrushSizeEdit" to="." method="_on_RightBrushSizeEdit_value_changed"]
+[connection signal="value_changed" from="UI/ToolPanel/Tools/ToolOptions/RightToolOptions/InterpolateColor/RightInterpolateFactor" to="." method="_on_RightInterpolateFactor_value_changed"]
 [connection signal="mouse_entered" from="UI/CanvasAndTimeline/HBoxContainer/ViewportContainer" to="." method="_on_ViewportContainer_mouse_entered"]
 [connection signal="mouse_exited" from="UI/CanvasAndTimeline/HBoxContainer/ViewportContainer" to="." method="_on_ViewportContainer_mouse_exited"]
 [connection signal="mouse_entered" from="UI/CanvasAndTimeline/HBoxContainer/ViewportContainer2" to="." method="_on_ViewportContainer_mouse_entered"]

Scripts/BrushButton.gd

@@ -8,7 +8,10 @@ func _on_BrushButton_pressed() -> void:
 		Global.current_left_brush_type = brush_type
 		if custom_brush_index > -1:
 			Global.custom_left_brush_index = custom_brush_index
+			Global.update_left_custom_brush()
+	
 	elif Input.is_action_just_released("right_mouse"):
 		Global.current_right_brush_type = brush_type
 		if custom_brush_index > -1:
 			Global.custom_right_brush_index = custom_brush_index
+			Global.update_right_custom_brush()

Scripts/Canvas.gd

@@ -245,17 +245,30 @@ func _draw() -> void:
 			draw_line(Vector2(location.x, y), Vector2(size.x, y), Color.black, true)
 	
 	#Draw rectangle to indicate the pixel currently being hovered on
-	var mouse_pos := get_local_mouse_position() - location
+	var mouse_pos := get_local_mouse_position() + location
 	if point_in_rectangle(mouse_pos, location, location + size):
 		mouse_pos = mouse_pos.floor()
 		if Global.left_square_indicator_visible:
+			match Global.current_left_brush_type:
+				Global.BRUSH_TYPES.PIXEL:
 					var start_pos_x = mouse_pos.x - (Global.left_brush_size >> 1)
 					var start_pos_y = mouse_pos.y - (Global.left_brush_size >> 1)
 					draw_rect(Rect2(start_pos_x, start_pos_y, Global.left_brush_size, Global.left_brush_size), Color.blue, false)
+				Global.BRUSH_TYPES.CUSTOM:
+					var custom_brush_size = Global.custom_left_brush_image.get_size()
+					var dst : Vector2 = mouse_pos - custom_brush_size / 4
+					draw_texture(Global.custom_left_brush_texture, dst)
+		
 		if Global.right_square_indicator_visible:
+			match Global.current_right_brush_type:
+				Global.BRUSH_TYPES.PIXEL:
 					var start_pos_x = mouse_pos.x - (Global.right_brush_size >> 1)
 					var start_pos_y = mouse_pos.y - (Global.right_brush_size >> 1)
 					draw_rect(Rect2(start_pos_x, start_pos_y, Global.right_brush_size, Global.right_brush_size), Color.red, false)
+				Global.BRUSH_TYPES.CUSTOM:
+					var custom_brush_size = Global.custom_right_brush_image.get_size()
+					var dst : Vector2 = mouse_pos - custom_brush_size / 4
+					draw_texture(Global.custom_right_brush_texture, dst)
 
 func generate_layer_panels() -> void:
 	for child in Global.vbox_layer_container.get_children():
@@ -295,33 +308,33 @@ func pencil_and_eraser(mouse_pos : Vector2, color : Color, current_mouse_button
 		var brush_size := 1
 		var brush_type = Global.BRUSH_TYPES.PIXEL
 		var brush_index := -1
-		var interpolate_factor := 0.5
+		var custom_brush_image : Image
 		if current_mouse_button == "left_mouse":
 			brush_size = Global.left_brush_size
 			brush_type = Global.current_left_brush_type
 			brush_index = Global.custom_left_brush_index
-			interpolate_factor = Global.left_interpolate_slider.value
+			custom_brush_image = Global.custom_left_brush_image
 		elif current_mouse_button == "right_mouse":
 			brush_size = Global.right_brush_size
 			brush_type = Global.current_right_brush_type
 			brush_index = Global.custom_right_brush_index
-			interpolate_factor = Global.right_interpolate_slider.value
+			custom_brush_image = Global.custom_right_brush_image
 			
 		if is_making_line:
-			fill_gaps(mouse_pos, color, brush_size, brush_type, brush_index, interpolate_factor)
+			fill_gaps(mouse_pos, color, brush_size, brush_type, brush_index, custom_brush_image)
 			is_making_line = false
 			line_2d.queue_free()
 		else:
 			if point_in_rectangle(mouse_pos, location, location + size):
 				mouse_inside_canvas = true
 				#Draw
-				draw_pixel(mouse_pos, color, brush_size, brush_type, brush_index, interpolate_factor)
+				draw_pixel(mouse_pos, color, brush_size, brush_type, brush_index, custom_brush_image)
-				fill_gaps(mouse_pos, color, brush_size, brush_type, brush_index, interpolate_factor) #Fill the gaps
+				fill_gaps(mouse_pos, color, brush_size, brush_type, brush_index, custom_brush_image) #Fill the gaps
 			#If mouse is not inside bounds but it used to be, fill the gaps
 			elif point_in_rectangle(previous_mouse_pos, location, location + size):
-				fill_gaps(mouse_pos, color, brush_size, brush_type, brush_index, interpolate_factor)
+				fill_gaps(mouse_pos, color, brush_size, brush_type, brush_index, custom_brush_image)
 
-func draw_pixel(pos : Vector2, color : Color, brush_size : int, brush_type : int, brush_index : int, interpolate_factor : float) -> void:
+func draw_pixel(pos : Vector2, color : Color, brush_size : int, brush_type : int, brush_index : int, custom_brush_image : Image) -> void:
 	if Global.can_draw && Global.has_focus && Global.current_frame == frame:
 		var west_limit := location.x
 		var east_limit := location.x + size.x
@@ -352,26 +365,26 @@ func draw_pixel(pos : Vector2, color : Color, brush_size : int, brush_type : int
 								sprite_changed_this_frame = true
 			
 			Global.BRUSH_TYPES.CUSTOM:
-				var custom_brush := Image.new()
+				var custom_brush_size = custom_brush_image.get_size()
-				custom_brush.copy_from(Global.custom_brushes[brush_index])
-				var custom_brush_blended := blend_image_with_color(custom_brush, color, interpolate_factor)
-				var custom_brush_size = custom_brush_blended.get_size()
-				custom_brush_blended.resize(custom_brush_size.x * brush_size, custom_brush_size.y * brush_size, Image.INTERPOLATE_NEAREST)
-				custom_brush_size = custom_brush_blended.get_size()
 				var dst : Vector2 = pos - custom_brush_size / 4
 				var src_rect := Rect2(Vector2.ZERO, custom_brush_size)
 				#src_rect = src_rect.clip(Rect2(west_limit - dst.x, north_limit - dst.y, east_limit - custom_brush_size.x, south_limit - custom_brush_size.y))
 				
 				if color.a > 0: #If it's the pencil
-					layers[current_layer_index][0].blend_rect(custom_brush_blended, src_rect, dst)
+					layers[current_layer_index][0].blend_rect(custom_brush_image, src_rect, dst)
 				else: #if it's transparent - if it's the eraser
+					var custom_brush := Image.new()
+					custom_brush.copy_from(Global.custom_brushes[brush_index])
+					custom_brush_size = custom_brush.get_size()
+					custom_brush.resize(custom_brush_size.x * brush_size, custom_brush_size.y * brush_size, Image.INTERPOLATE_NEAREST)
+					var custom_brush_blended = Global.blend_image_with_color(custom_brush, color, 1)
 					layers[current_layer_index][0].blit_rect_mask(custom_brush_blended, custom_brush, src_rect, dst)
 				layers[current_layer_index][0].lock()
 				update_texture(current_layer_index)
 
 #Bresenham's Algorithm
 #Thanks to https://godotengine.org/qa/35276/tile-based-line-drawing-algorithm-efficiency
-func fill_gaps(mouse_pos : Vector2, color : Color, brush_size : int, brush_type : int, brush_index : int, interpolate_factor : float) -> void:
+func fill_gaps(mouse_pos : Vector2, color : Color, brush_size : int, brush_type : int, brush_index : int, custom_brush_image : Image) -> void:
 	var previous_mouse_pos_floored = previous_mouse_pos.floor()
 	var mouse_pos_floored = mouse_pos.floor()
 	mouse_pos_floored.x = clamp(mouse_pos_floored.x, location.x - 1, location.x + size.x)
@@ -385,7 +398,7 @@ func fill_gaps(mouse_pos : Vector2, color : Color, brush_size : int, brush_type
 	var x = previous_mouse_pos_floored.x
 	var y = previous_mouse_pos_floored.y
 	while !(x == mouse_pos_floored.x && y == mouse_pos_floored.y):
-		draw_pixel(Vector2(x, y), color, brush_size, brush_type, brush_index, interpolate_factor)
+		draw_pixel(Vector2(x, y), color, brush_size, brush_type, brush_index, custom_brush_image)
 		e2 = err << 1
 		if e2 >= dy:
 			err += dy
@@ -439,22 +452,5 @@ func flood_fill(pos : Vector2, target_color : Color, replace_color : Color) -> v
 func point_in_rectangle(p : Vector2, coord1 : Vector2, coord2 : Vector2) -> bool:
 	return p.x > coord1.x && p.y > coord1.y && p.x < coord2.x && p.y < coord2.y
 
-func blend_image_with_color(image : Image, color : Color, interpolate_factor : float) -> Image:
-	var blended_image := Image.new()
-	blended_image.copy_from(image)
-	var size := image.get_size()
-	blended_image.lock()
-	for xx in size.x:
-		for yy in size.y:
-			if color.a > 0: #If it's the pencil
-				var current_color := blended_image.get_pixel(xx, yy)
-				if current_color.a > 0:
-					#var blended_color = current_color.blend(color)
-					var new_color := current_color.linear_interpolate(color, interpolate_factor)
-					blended_image.set_pixel(xx, yy, new_color)
-			else: #If color is transparent - if it's the eraser
-				blended_image.set_pixel(xx, yy, Color(0, 0, 0, 0))
-	return blended_image
-
 func _on_Timer_timeout() -> void:
 	Global.can_draw = true

Scripts/Global.gd

@@ -82,6 +82,14 @@ var custom_brushes := []
 var custom_left_brush_index := -1
 # warning-ignore:unused_class_variable
 var custom_right_brush_index := -1
+# warning-ignore:unused_class_variable
+var custom_left_brush_image : Image
+# warning-ignore:unused_class_variable
+var custom_right_brush_image : Image
+# warning-ignore:unused_class_variable
+var custom_left_brush_texture := ImageTexture.new()
+# warning-ignore:unused_class_variable
+var custom_right_brush_texture := ImageTexture.new()
 
 
 func _ready() -> void:
@@ -168,10 +176,43 @@ func set_current_frame_label(value) -> void:
 
 func create_brush_button(brush_img : Image) -> void:
 	var brush_button = load("res://Prefabs/BrushButton.tscn").instance()
-	brush_button.brush_type = Global.BRUSH_TYPES.CUSTOM
+	brush_button.brush_type = BRUSH_TYPES.CUSTOM
-	brush_button.custom_brush_index = Global.custom_brushes.size() - 1
+	brush_button.custom_brush_index = custom_brushes.size() - 1
 	var brush_tex := ImageTexture.new()
 	brush_tex.create_from_image(brush_img, 0)
 	brush_button.get_child(0).texture = brush_tex
 	var hbox_container := find_node_by_name(get_tree().get_root(), "BrushHBoxContainer")
 	hbox_container.add_child(brush_button)
+	
+func update_left_custom_brush() -> void:
+	var custom_brush := Image.new()
+	custom_brush.copy_from(custom_brushes[custom_left_brush_index])
+	var custom_brush_size = custom_brush.get_size()
+	custom_brush.resize(custom_brush_size.x * left_brush_size, custom_brush_size.y * left_brush_size, Image.INTERPOLATE_NEAREST)
+	custom_left_brush_image = blend_image_with_color(custom_brush, left_color_picker.color, left_interpolate_slider.value)
+	custom_left_brush_texture.create_from_image(custom_left_brush_image, 0)
+	
+func update_right_custom_brush() -> void:
+	var custom_brush := Image.new()
+	custom_brush.copy_from(custom_brushes[custom_right_brush_index])
+	var custom_brush_size = custom_brush.get_size()
+	custom_brush.resize(custom_brush_size.x * right_brush_size, custom_brush_size.y * right_brush_size, Image.INTERPOLATE_NEAREST)
+	custom_right_brush_image = blend_image_with_color(custom_brush, right_color_picker.color, right_interpolate_slider.value)
+	custom_right_brush_texture.create_from_image(custom_right_brush_image, 0)
+
+func blend_image_with_color(image : Image, color : Color, interpolate_factor : float) -> Image:
+	var blended_image := Image.new()
+	blended_image.copy_from(image)
+	var size := image.get_size()
+	blended_image.lock()
+	for xx in size.x:
+		for yy in size.y:
+			if color.a > 0: #If it's the pencil
+				var current_color := blended_image.get_pixel(xx, yy)
+				if current_color.a > 0:
+					#var blended_color = current_color.blend(color)
+					var new_color := current_color.linear_interpolate(color, interpolate_factor)
+					blended_image.set_pixel(xx, yy, new_color)
+			else: #If color is transparent - if it's the eraser
+				blended_image.set_pixel(xx, yy, Color(0, 0, 0, 0))
+	return blended_image

Scripts/Main.gd

@@ -550,10 +550,12 @@ func _on_RightIndicatorCheckbox_toggled(button_pressed) -> void:
 func _on_LeftBrushSizeEdit_value_changed(value) -> void:
 	var new_size = int(value)
 	Global.left_brush_size = new_size
+	update_left_custom_brush()
 
 func _on_RightBrushSizeEdit_value_changed(value) -> void:
 	var new_size = int(value)
 	Global.right_brush_size = new_size
+	update_right_custom_brush()
 
 func _on_AddFrame_pressed() -> void:
 	var canvas = load("res://Prefabs/Canvas.tscn").instance()
@@ -745,3 +747,24 @@ func _on_SplitScreenButton_toggled(button_pressed) -> void:
 		Global.split_screen_button.text = "<"
 		Global.viewport_separator.visible = false
 		Global.second_viewport.visible = false
+
+# warning-ignore:unused_argument
+func _on_LeftColorPickerButton_color_changed(color : Color) -> void:
+	update_left_custom_brush()
+
+# warning-ignore:unused_argument
+func _on_RightColorPickerButton_color_changed(color : Color) -> void:
+	update_right_custom_brush()
+
+# warning-ignore:unused_argument
+func _on_LeftInterpolateFactor_value_changed(value : float) -> void:
+	update_left_custom_brush()
+
+# warning-ignore:unused_argument
+func _on_RightInterpolateFactor_value_changed(value : float) -> void:
+	update_right_custom_brush()
+
+func update_left_custom_brush() -> void:
+	Global.update_left_custom_brush()
+func update_right_custom_brush() -> void:
+	Global.update_right_custom_brush()

Scripts/SecondViewport.gd

@@ -1,13 +1,5 @@
 extends Viewport
 
-# Declare member variables here. Examples:
-# var a = 2
-# var b = "text"
-
 # Called when the node enters the scene tree for the first time.
-func _ready():
+func _ready() -> void:
 	world_2d = $"../../ViewportContainer/Viewport".world_2d
-
-# Called every frame. 'delta' is the elapsed time since the previous frame.
-#func _process(delta):
-#	pass