StyleBoxLine in Godot – Complete Guide

Welcome to our tutorial on the StyleBoxLine class in Godot 4! If you’re looking to add polished UI elements and separators to your game projects, mastering StyleBoxLine is a must. Not only does it enhance the visual appeal, but it also contributes significantly to the user interface’s functionality. We will dive into the world of this versatile class and understand how you can use it to create clean and crisp lines within your Godot application. Whether you’re new to Godot or a seasoned developer, this guide will walk you through the basics and beyond of using StyleBoxLine in your projects.

What is StyleBoxLine?

The StyleBoxLine class is essentially a subclass within the Godot engine used to generate single-line style boxes. This UI element is evidently simple, but don’t be fooled—its applications within game design are both critical and diverse.

What is it used for?

The primary use of a StyleBoxLine is to serve as a separator. Whether you’re organizing content in your game’s HUD (Heads-Up Display), menu screens, or even for aesthetic detailing, StyleBoxLine comes in handy. You can adjust properties such as color, thickness, and direction, making it incredibly versatile for your UI needs.

Why should I learn it?

As a game developer, understanding the tools at your disposal is crucial for creating an engaging player experience. Learning how to use StyleBoxLine can:

– Help you create better-organized UIs.
– Allow you to add a layer of polish that can set your game apart.
– Improve the overall feel and functionality of your game interfaces.

With this knowledge, you can elevate the quality of your game’s presentation, making it not only more visually appealing, but also easier and more intuitive for players to navigate. Let’s get started with creating our first StyleBoxLine!

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Creating a Basic StyleBoxLine

To start with the basics, let’s create a StyleBoxLine in Godot and see how it looks:

var line =
line.color = Color(1, 0, 0) # Red color
line.thickness = 2

To implement our newly created StyleBoxLine, we need to apply it to a Control node, like a Panel or Button. Here’s how you can set it as the `panel` node’s custom style:

var panel =
panel.add_stylebox_override("panel", line)

This code will create a red line with a thickness of 2 pixels on the panel.

Adjusting Line Properties

StyleBoxLine comes with various properties that you can adjust to fit your UI’s design aesthetic. Let’s explore changing the thickness, color, and expand margin.

To modify the thickness of your StyleBoxLine:

line.thickness = 4  # Increases the line thickness

Changing the color is straightforward as well:

line.color = Color(0, 0, 1) # Changes line color to blue

Another interesting property is the expand margin, which allows your line to expand outside the bounds of its assigned area. Here’s how to set it:

line.expand_margin_size = 10  # Expands the line 10 pixels outwards

Vertical & Horizontal Lines

Sometimes you might want a separator that is either vertical or horizontal. StyleBoxLine can do both; you just need to specify the direction when configuring it.

For a horizontal line, we’d adjust the properties like this:

var horizontal_line =
horizontal_line.thickness = 2
horizontal_line.color = Color(0.5, 0.5, 0.5)  # Grey color
# Set expand margin if needed
horizontal_line.expand_margin_size = 5

And for a vertical line, you would simply rotate it or apply it to a vertically oriented panel:

var vertical_line =
vertical_line.thickness = 2
vertical_line.color = Color(0.5, 0.5, 0.5)  # Grey color
# Set expand margin if needed
vertical_line.expand_margin_size = 5
# For a vertical separator, we use a VSeparator node
var separator =
separator.custom_styles["separator"] = vertical_line

Combining Lines with Other UI Elements

A separator line often accompanies other UI elements. Let’s see how we can meaningfully integrate a StyleBoxLine with a Label node to create a title with a line underneath.

var label =
label.text = "Game Settings"

var underline =
underline.color = Color(0, 1, 0)  # Green color
label.add_stylebox_override("panel", underline)

In this example, we’ve created a label for ‘Game Settings’ and placed a green underline beneath it to signify its importance and to improve readability.

These are the basics of using the StyleBoxLine class in Godot. As you can see, with a few lines of code, you can start experimenting with UI elements that look a lot more dynamic and polished. What’s more, StyleBoxLine can be tweaked even further for more complex user interfaces, providing an invaluable tool in your game development arsenal.As we dive deeper into the StyleBoxLine possibilities, we’ll explore additional aspects such as creating dashed lines, adjusting the anti-aliasing, and dynamically manipulating StyleBoxLine properties through code. These advanced techniques can further refine the look and responsiveness of your in-game UI.

Creating Dashed Lines

One common variant of line separators is the dashed line. While Godot’s StyleBoxLine does not have a built-in dashed line pattern, we can create a similar effect using the draw method within a Control node’s _draw callback.

class_name DashedLineSeparator extends Control

func _draw():
	var dash_length = 10
	var space_length = 5
	var pos = 0
	var end_pos = rect_size.x  # Assuming a horizontal line

	while pos < end_pos:
		draw_line(Vector2(pos, rect_size.y / 2), Vector2(pos + dash_length, rect_size.y / 2), Color(1, 0, 0))
		pos += dash_length + space_length

With this code, you can create a horizontal dashed line within a custom Control node. Adjust the `dash_length` and `space_length` values to get the desired look.

Adjusting Anti-aliasing

If you need cleaner lines without the pixelated look, StyleBoxLine also includes an anti-alias property. For the smoothest edges on your lines:

line.anti_aliased = true

This option enables the anti-aliasing algorithm for a softer appearance, especially noticeable in high-resolution games or when using diagonal lines.

Dynamic Property Manipulation

You may want to change the properties of your StyleBoxLine dynamically based on player interactions or events within the game. Here’s an example of how you can change the line’s color when a player hovers over a button:

func _on_Button_mouse_entered():
	line.color = Color(1, 1, 0)  # Change to yellow on hover

func _on_Button_mouse_exited():
	line.color = Color(1, 0, 0)  # Change back to red when not hovered

Remember to connect these functions to the corresponding signals for the Button node.

Expanding to Fit Screen Width

There may be situations where you want a horizontal line to span the entire width of the game window. This can be achieved by adjusting the expand margin size to a sufficiently large value, like so:

line.expand_margin_size = get_viewport_rect().size.x

This will ensure that the line extends to the edges of the screen, irrespective of the current window or screen size.

Styling Separator Nodes

Godot provides dedicated nodes such as `HSeparator` and `VSeparator` that are designed to be used as horizontal and vertical separators, respectively. You can apply a StyleBoxLine directly to these:

var h_separator =
h_separator.custom_styles["separator"] = line

var v_separator =
v_separator.custom_styles["separator"] = line

By combining these styling techniques and using Godot’s nodes effectively, you can achieve a professional and cohesive look for your UI that enhances the overall user experience. Remember that experimenting with the properties and practicing different applications will perfect your ability to effectively use StyleBoxLine in Godot.Continuing from where we left off, a common technique in game UI design is to use style boxes to dynamically respond to player inputs. This could involve changing the appearance of buttons when clicked or highlighting menu options as the player navigates through them.

Responding to Button States

Godot makes it easy to style buttons for different states, such as pressed or focused. Here’s how you can adapt your StyleBoxLine to change when a button is pressed:

func _ready():
	var button =
	button.text = "Click Me!"

	var normal_line =
	normal_line.color = Color(0, 0, 1)  # Blue line for normal state

	var pressed_line =
	pressed_line.color = Color(1, 0, 0)  # Red line for pressed state

	button.add_stylebox_override("normal", normal_line)
	button.add_stylebox_override("pressed", pressed_line)

In this example, a blue line represents the button’s default state, while a red line signifies its pressed state.

Highlighting Menu Options

For menus, visual feedback is key to showing players which option they are about to select. Using StyleBoxLine, we can highlight the currently focused menu option elegantly.

func _ready():
	var menu_items = ["Start Game", "Options", "Quit"]
	for item in menu_items:
		var label =
		label.text = item
		if item == "Options":
			var highlight_line =
			highlight_line.color = Color(0, 1, 0)  # Green highlight for focused item
			label.add_stylebox_override("panel", highlight_line)

Here, the “Options” label will have a green highlight, indicating it’s focused or selected.

Animating Styles

Animation can add a dynamic flair to your UI elements. Here’s an example of animating the thickness of a StyleBoxLine to subtly draw attention to a UI element:

var anim =
anim.track_set_path(0, "line:thickness")
anim.track_insert_key(0, 0.0, 2)
anim.track_insert_key(0, 1.0, 4)

var animPlayer =
animPlayer.add_animation("thicken_line", anim)"thicken_line")

The above code animates the thickness of the line to oscillate between 2 and 4 pixels.

Using StyleBoxLine with Theme Overrides

Themes in Godot allow you to have a consistent design throughout your game. Here’s a snippet showing how you could apply a StyleBoxLine across all button nodes in a theme:

var theme =
var default_line =
default_line.color = Color(0.8, 0.8, 0.8)  # Default color for theme style boxes

theme.set_stylebox("normal", "Button", default_line)

Now, all buttons in the game will use the `default_line` StyleBoxLine for their normal state, creating a consistent look and feel in your game.

By integrating these advanced techniques and customizations, you can ensure that your UI is not only functional but also pleasing to the eye and engaging for the player. These examples should serve as a foundation, inspiring you to explore the endless creative possibilities that StyleBoxLine can offer in your Godot projects.

Continue Your Game Development Journey

Now that you’ve had a taste of the power of StyleBoxLine in Godot, you might be wondering where to go next to continue honing your game development skills. We’ve got you covered! Our Godot Game Development Mini-Degree is an excellent next step for those of you looking to deepen your understanding and expertise in creating games with Godot.

In our comprehensive course collection, you’ll explore not just the UI intricacies, but also dive into creating 2D and 3D games, mastering gameplay mechanics, and designing engaging game worlds across various genres. Our structured lessons and flexible learning options ensure that you can learn at your own pace and build a portfolio of real projects to showcase your skills.

Moreover, for a wider array of tutorials and courses that cover various aspects of Godot, check out our complete range of Godot courses. Whether you’re just starting out or seeking to specialize your game development knowledge, our courses can help you progress from beginner to professional game developer. Join Zenva Academy to boost your career with over 250 supported courses while learning how to code, create games, and earn certificates. Your journey to becoming a game development pro begins here!


Congratulations on taking this valuable step towards mastering the art of UI design in Godot with the StyleBoxLine class! We’ve only scratched the surface of what’s possible in creating immersive and visually compelling game interfaces. These skills not only make your games look professional but also enhance the overall gaming experience for your players. Remember, creating games is an ever-evolving journey, and every new technique you learn paves the way to realizing your most imaginative game concepts.

If you’re eager to keep learning and expanding your development repertoire, join us at our Godot Game Development Mini-Degree. Here, you’ll find the resources, community, and expertise to transform your game ideas into reality. Whether it’s Godot, coding, or any other aspect of game development you’re curious about, we at Zenva Academy are here to support you every step of the way. Start your next chapter in game development with us, because there’s always a new skill to master and a new challenge to conquer!

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