CodeHighlighter in Godot – Complete Guide

Welcome to our exploration of the CodeHighlighter class in Godot 4! If you’ve been dabbling in game development, or you’re intrigued by the idea of bringing your code to life with crystal clear clarity, then you’re in just the right place. This tutorial will not only introduce you to the realm of syntax highlighting in Godot’s robust TextEdit control but will also guide you through practical examples that will help you harness this powerful feature. As we venture through this journey together, you’ll understand how CodeHighlighter can elevate your coding experience, making it both efficient and visually appealing.

What is CodeHighlighter?

CodeHighlighter is a dedicated class in Godot 4 designed to enhance the readability of code within the engine’s TextEdit control. Just as an artist uses different colors to bring a painting to life, CodeHighlighter allows programmers to assign colors to various elements of code — such as strings, comments, and functions — making it easier to distinguish between them at a glance.

What is it for?

At its core, CodeHighlighter serves to create a more intuitive editing environment. It is incredibly useful for spotting errors, understanding code structure, and navigating complex scripts. Whether you’re working on a small script or a large game project, having well-organized and visually differentiated code can significantly streamline your development process.

Why Should I Learn It?

Syntax highlighting is more than just an aesthetic addition; it’s a crucial component of modern coding practices. Learning to effectively use CodeHighlighter in Godot 4 can help you:

  • Reduce eye strain: Color-coded text is easier on the eyes, especially during long coding sessions.
  • Debug with ease: Quickly identify and correct syntax errors or misplaced code elements.
  • Improve code comprehension: For both you and anyone else who might read your code, distinct colors aid in understanding the logic and structure at a glance.

By incorporating these techniques into your workflow, you’re not only investing in a more efficient way to code but also paving a smoother road towards becoming an advanced Godot developer.

CTA Small Image

Setting Up Your Godot Project for Syntax Highlighting

Before diving into the examples, let’s set the stage for incorporating syntax highlighting into your Godot 4 project. To start, you’ll need to create a TextEdit node which will serve as the canvas for your code. Follow these steps to get going:

  1. Open Godot and create a new project or go to your existing one.
  2. Add a new TextEdit node to the scene tree.
  3. In the Inspector, ensure that the ‘syntax_highlighting’ property is set to ‘true’ to enable the feature.

Once you have your TextEdit node set up, here’s a simple GDScript snippet to get you started with customizing your syntax highlighting rules:

var code_highlighter =
var text_edit = $TextEdit

# Define your syntax highlighting rules here
code_highlighter.add_color_region("/*", "*/", Color(0.5, 0.5, 0.5), false)
code_highlighter.add_keyword_color("func", Color(0, 1, 0))

Creating Basic Syntax Highlighting Rules

Now, let’s write some rules for our CodeHighlighter. Each rule you create will tell CodeHighlighter how to color different parts of the text.

For highlighting comments, define two string delimiters that mark the beginning and end of a comment, and set the desired color.

code_highlighter.add_color_region("#", "\n", Color(0.5, 0.5, 0.5), false) # For single line comments
code_highlighter.add_color_region("'''", "'''", Color(0.5, 0.5, 0.5), false) # For block comments

For highlighting keywords such as ‘var’, ‘func’, or any specific terms you want to stand out, use ‘add_keyword_color’.

code_highlighter.add_keyword_color("var", Color(1, 0.6, 0.2))
code_highlighter.add_keyword_color("func", Color(0.2, 0.7, 0.3))

Highlighting strings with a customized color helps distinguish them from other code elements.

code_highlighter.add_color_region("\"", "\"", Color(0.8, 0.3, 0.3), true)

Operators and symbols can be made distinguishable by assigning them a separate color.

code_highlighter.add_symbol_color("+", Color(0.8, 0.8, 0.0))
code_highlighter.add_symbol_color("=", Color(0.8, 0.8, 0.0))
code_highlighter.add_symbol_color("-", Color(0.8, 0.8, 0.0))
code_highlighter.add_symbol_color("*", Color(0.8, 0.8, 0.0))

Enhancing Readability with More Advanced Rules

Taking syntax highlighting one step further, you can customize your highlighting for even more specific cases to enhance readability further.

Highlighting function names separately from other keywords adds a layer of distinction for quickly identifying functions within the code.

# Assume 'extract_functions' is a function you've defined to parse functions from your code
var function_names = extract_functions(code)
for function_name in function_names:
    code_highlighter.add_keyword_color(function_name, Color(0.2, 0.2, 1.0))

Integrating theme-based colors can help adapt the highlighting rules to fit the general color scheme of your project or preferred coding environment.

# Set a theme for your code editor
var background_color = Color(0.1, 0.1, 0.1)
var text_color = Color(0.9, 0.9, 0.9)

text_edit.add_color_override("background_color", background_color)
text_edit.add_color_override("font_color", text_color)

Remember, the intent behind adding syntax highlighting is to create a text-editing environment that is visually aligned with your understanding and preferences. By experimenting with these examples and exploring the possibilities within the CodeHighlighter class, you can tailor your Godot TextEdit exactly to your needs and ensure a pleasant coding experience.Now that we’ve covered the basics of CodeHighlighter, let’s explore more sophisticated examples to truly make your code stand out and enhance its legibility.

Customizing the CodeHighlighter Class for Extended Functionality

While Godot’s default CodeHighlighter is quite powerful, there might be situations where you want to extend its functionality to fit your specific needs. This could involve creating a custom CodeHighlighter script that inherits from the base class and overrides certain methods.

For instance, consider you want to add dynamic highlighting for variables you’ve declared. You could override the _update_syntax_highlighting method in your custom class to achieve this:

extends CodeHighlighter

func _update_syntax_highlighting(line):
    var words = line.split(" ")
    for word in words:
        if word in _your_variables_array:
            add_keyword_color(word, Color(0.7, 0.7, 1.0))

This snippet introduces the concept of highlighting variables that you keep track of in a dedicated array. The method ‘_update_syntax_highlighting’ updates the highlighting upon changes.

Matching Complex Patterns with Regular Expressions

Regular expressions are a powerful tool for pattern matching within strings. Godot currently does not support regex-based syntax highlighting directly in CodeHighlighter, but you can implement such logic by processing the text before setting it in TextEdit.

extends CodeHighlighter

var function_pattern =

func highlight_functions(code):
    var result =
    while result != null:
        var function_name = result.get_string(1)
        add_keyword_color(function_name, Color(1, 0.5, 0))
        result =

By compiling a regex to capture your functions and applying it to your code, you are able to extract these functions and highlight them accordingly.

Highlighting All Occurrences of a Selected Word

Enhance your code editing by automatically highlighting all instances of a selected word throughout the document. This can greatly assist in refactoring or understanding usage patterns:

func highlight_selected_word(word):
    var start_line = 0
    var line_count = text_edit.get_line_count()
    while start_line < line_count:
        var line_text = text_edit.get_line(start_line)
        var word_idx = line_text.find(word)
        while word_idx != -1:
            code_highlighter.add_word_highlight(word, start_line, word_idx, Color(1, 1, 0))
            word_idx = line_text.find(word, word_idx + word.length())
        start_line += 1

This method utilizes the ‘find’ function to search each line for the target word and then highlights it with the specified color.

Integrating Syntax Highlighting into Auto-complete

For an even more refined coding experience, your custom CodeHighlighter can work in tandem with a script for auto-complete features.

func _on_TextEdit_text_changed():
    var code = text_edit.get_text()

func update_autocomplete(code):
    var tokens = get_code_tokens(code)
    var completion_list = []
    for token in tokens:
        if is_valid_completion(token):

In this example, ‘update_autocomplete’ could be a function where you process your code to extract tokens (such as function names, variables, or custom keywords) that can be used for an auto-complete feature.

Combining the above examples and tips into your code editor will surely bring out the best in your game scripting workflow with Godot. The power of CodeHighlighter lies in its flexibility, and by mastering its features, you ensure that your code is not only functional but also a well-organized and visually appealing masterpiece. Remember, good syntax highlighting is akin to a map through your codebase, allowing you to navigate the terrain of your game’s logic with confidence and clarity.Certainly! Let’s delve deeper into the world of syntax highlighting with more examples that can make your coding in Godot even more efficient and dynamic.

Advanced Code Highlighting Techniques

To further enhance the usability of the CodeHighlighter class, we can implement a range of specialized techniques. From customizing the colors of different data types to implementing listeners for code changes, the possibilities are nearly endless.

Highlighting Different Data Types
Identifying data types at a glance aids in understanding how values are manipulated within your code. Here is an example of how to differentiate between different data types:

code_highlighter.add_keyword_color("var", Color(0.5, 0.5, 1.0))
code_highlighter.add_keyword_color("int", Color(1.0, 0.5, 0.5))
code_highlighter.add_keyword_color("String", Color(0.5, 1.0, 0.5))
code_highlighter.add_keyword_color("Array", Color(1.0, 1.0, 0.5))

Dynamic Highlighting Based on User Input
Create a user-interactive environment by implementing dynamic highlighting based on input from the user. For example, let’s say you want to highlight all occurrences of a word typed into a search field:

func _on_SearchField_text_changed(new_text):
    var search_word = new_text.strip()
    if search_word.empty():
        code_highlighter.add_custom_highlight(search_word, Color(1.0, 1.0, 0.0))

Listening to Code Changes
To create an interactive experience where highlights update in real-time as the user types, you can connect signals in TextEdit that notify you of changes:

text_edit.connect("text_changed", self, "_on_TextEdit_text_changed")

func _on_TextEdit_text_changed():
    # Insert the logic to update your highlighting here.

Syntax Highlighting for Preprocessor Directives
For languages or scripting environments that use preprocessor directives or annotations, you can make them stand out:

code_highlighter.add_color_region("@", " ", Color(0.7, 0.4, 0.9), false)

Temporary Highlights for Debugging
Imagine you are debugging and want to quickly highlight lines where variables are modified. You can achieve this with:

func highlight_variable_modifications(variable_name):
    for line_index in text_edit.get_line_count():
        var line = text_edit.get_line(line_index)
        if line.find(variable_name) != -1:
            code_highlighter.add_line_highlight(line_index, Color(1.0, 0.8, 0.6))

Version Control Integration
Enhance your version control by highlighting lines that have been modified since the last commit:

# Assume 'get_modified_lines' is a function that returns an array of line numbers
var modified_lines = get_modified_lines()
for line in modified_lines:
    code_highlighter.add_line_highlight(line, Color(0.9, 0.9, 0.4))

Developing a sound highlighting strategy can improve not only the readability of your code but also its maintainability. By tailoring these examples to suit your specific coding habits and needs, you’ll be taking a significant step towards a more productive and enjoyable game development experience in Godot 4.

Remember to always test your highlighting rules thoroughly. Good syntax highlighting should aid in code comprehension without causing distraction or confusion. Consistency in your color scheme and thoughtful application of highlighting rules will make your Godot editor a powerful ally in your game development adventures.

Continuing Your Godot Journey

Congratulations on taking your first steps with CodeHighlighter in Godot 4! As you’ve learned, mastering syntax highlighting is crucial for creating clean, readable, and maintainable code. While we’ve covered quite a bit, there’s still a vast world within Godot waiting for you to explore.

We encourage you to keep honing your skills and delving deeper into Godot’s capabilities. A great next step is checking out our Godot Game Development Mini-Degree. This program is designed to equip you with the knowledge required to build cross-platform games from scratch. The Godot 4 Game Development Mini-Degree offers in-depth courses, whether you’re just starting out or you’re seeking to sharpen your existing skills further.

For those who wish to broaden their learning path even more, our collection of Godot courses covers a diverse array of topics. From creating immersive 2D and 3D games to understanding complex game mechanics across various genres, Zenva provides comprehensive resources to support your passion for game development.

Keep coding, keep creating, and most importantly, keep enjoying the journey. Your next game development breakthrough is just around the corner!


As we wrap up this tutorial, it’s clear that the capabilities of the CodeHighlighter class in Godot 4 can significantly amplify the efficiency and aesthetics of your code writing experience. With the examples and techniques you’ve learned today, we’re confident you’ll bring a new level of clarity and enjoyability to your game development process. Remember, the most beautiful code is not just about the logic it executes but also about the story it tells to the reader, and a well-highlighted script is an indispensable part of that narrative.

We at Zenva are excited to accompany you on your coding journey, providing you with the tools and knowledge you need to succeed. Don’t stop here; dive into our Godot Game Development Mini-Degree to unlock your full potential as a game developer. Whether you aim to create indie games, contribute to exciting projects, or even forge your path in the gaming industry, we’re here to guide you every step of the way. So go ahead, use these newfound skills to color your world of code, and let’s make something extraordinary together!

Python Blog Image

FINAL DAYS: Unlock coding courses in Unity, Godot, Unreal, Python and more.