Setting up the Custom Lit Shader Graph

Oct 13, 2025 by pinkandtrash.com 47 views

Introduction

In this article, we will explore how to create a sprite that is invisible when outside of a light source and visible when inside of it. This can be achieved using Unity's Custom Lit Shader Graph and a bit of creative problem-solving. We will walk through the process of setting up a new Custom Lit Shader Graph, creating a player with a sprite, and writing the necessary code to achieve the desired effect.

Setting up the Custom Lit Shader Graph

To start, we need to create a new Custom Lit Shader Graph. This can be done by following these steps:

Create a new Shader Graph: In the Unity editor, go to Window > Shader Graph. This will open the Shader Graph editor.
Create a new Custom Lit Shader Graph: In the Shader Graph editor, click on the Create button and select Custom Lit. This will create a new Custom Lit Shader Graph.
Configure the Shader Graph: In the Custom Lit Shader Graph, we need to configure the inputs and outputs. We will need to add the following inputs:
- Base Color: This will be the color of the sprite.
- Normal: This will be the normal map of the sprite.
- Emission: This will be the emission map of the sprite.
- Lighting: This will be the lighting information.
- Position: This will be the position of the sprite.
Configure the Outputs: We will need to add the following outputs:
- Color: This will be the final color of the sprite.
- Alpha: This will be the alpha value of the sprite.

Creating the Player with a Sprite

Now that we have set up the Custom Lit Shader Graph, we need to create a player with a sprite. This can be done by following these steps:

Create a new Player: In the Unity editor, go to GameObject > 3D Object > Player. This will create a new player game object.
Add a Sprite Renderer: To the player game object, add a Sprite Renderer component. This will allow us to render a sprite on the player.
Add a Custom Lit Shader Graph: To the player game object, add a Custom Lit Shader Graph component. This will allow us to use the Custom Lit Shader Graph to render the sprite.

Writing the Code to Hide the Sprite

Now that we have set up the Custom Lit Shader Graph and created a player with a sprite, we need to write the code to hide the sprite when it is outside of a light source and show it when it is inside of it. This can be done by using a Light 2D component and a Custom Lit Shader Graph.

Add a Light 2D: To the scene, add a Light 2D component. This will create a light source that we can use to illuminate the sprite.
Configure the Light 2D: In the Light 2D component, we need to configure the light source. We will need to set the Intensity to a value that will illuminate the sprite.
Add a Custom Lit Shader Graph: To the player game object, add a Custom Lit Shader Graph component. This will allow us to use the Custom Lit Shader Graph to render the sprite.
Write the Code: In the Custom Lit Shader Graph, we need to write the code to hide the sprite when it is outside of the light source and show it when it is inside of it. This can be done by using a Light 2D component and a Custom Lit Shader Graph.

Using a Light 2D to Illuminate the Sprite

To use a Light 2D to illuminate the sprite, we need to configure the light source to emit light in the direction of the sprite. This can be done by following these steps:

Add a Light 2D: To the scene, add a Light 2D component. This will create a light source that we can use to illuminate the sprite.
Configure the Light 2D: In the Light 2D component, we need to configure the light source. We will need to set the Intensity to a value that will illuminate the sprite.
Set the Light Direction: In the Light 2D component, we need to set the Light Direction to the direction of the sprite. This will ensure that the light source is emitting light in the direction of the sprite.

Using a Custom Lit Shader Graph to Render the Sprite

To use a Custom Lit Shader Graph to render the sprite, we need to configure the shader graph to use the light source to illuminate the sprite. This can be done by following these steps:

Add a Custom Lit Shader Graph: To the player game object, add a Custom Lit Shader Graph component. This will allow us to use the Custom Lit Shader Graph to render the sprite.
Configure the Shader Graph: In the Custom Lit Shader Graph, we need to configure the inputs and outputs. We will need to add the following inputs:
- Base Color: This will be the color of the sprite.
- Normal: This will be the normal map of the sprite.
- Emission: This will be the emission map of the sprite.
- Lighting: This will be the lighting information.
- Position: This will be the position of the sprite.
Configure the Outputs: We will need to add the following outputs:
- Color: This will be the final color of the sprite.
- Alpha: This will be the alpha value of the sprite.

Writing the Code to Hide the Sprite

Add a Light 2D: To the scene, add a Light 2D component. This will create a light source that we can use to illuminate the sprite.
Configure the Light 2D: In the Light 2D component, we need to configure the light source. We will need to set the Intensity to a value that will illuminate the sprite.
Add a Custom Lit Shader Graph: To the player game object, add a Custom Lit Shader Graph component. This will allow us to use the Custom Lit Shader Graph to render the sprite.
Write the Code: In the Custom Lit Shader Graph, we need to write the code to hide the sprite when it is outside of the light source and show it when it is inside of it. This can be done by using a Light 2D component and a Custom Lit Shader Graph.

Conclusion

In this article, we have explored how to create a sprite that is invisible when outside of a light source and visible when inside of it. We have used Unity's Custom Lit Shader Graph and a bit of creative problem-solving to achieve the desired effect. We have walked through the process of setting up a new Custom Lit Shader Graph, creating a player with a sprite, and writing the necessary code to hide the sprite when it is outside of a light source and show it when it is inside of it.

Tips and Variations

Use a different light source: Instead of using a Light 2D component, you can use a different light source such as a Point Light or a Spot Light.
Use a different shader graph: Instead of using a Custom Lit Shader Graph, you can use a different shader graph such as a Standard Shader or a Unlit Shader.
Add more features: You can add more features to the sprite such as animation, physics, or collision detection.

Common Issues and Solutions

Sprite is not visible: Make sure that the sprite is properly configured and that the light source is emitting light in the direction of the sprite.
Sprite is not hidden: Make sure that the sprite is properly configured and that the light source is not emitting light in the direction of the sprite.
Shader graph is not working: Make sure that the shader graph is properly configured and that the inputs and outputs are correctly set up.

Future Improvements

Add more features: You can add more features to the sprite such as animation, physics, or collision detection.
Improve performance: You can improve the performance of the sprite by using a more efficient shader graph or by optimizing the code.
Add more customization options: You can add more customization options to the sprite such as different light sources, different shader graphs, or different materials.
Unity 6: How to Hide a Sprite unless it is Illuminated by a Light 2D - Q&A =====================================================================

Introduction

In our previous article, we explored how to create a sprite that is invisible when outside of a light source and visible when inside of it. We used Unity's Custom Lit Shader Graph and a bit of creative problem-solving to achieve the desired effect. In this article, we will answer some of the most frequently asked questions about this technique.

Q: What is the difference between a Light 2D and a Point Light?

A: A Light 2D is a type of light source that emits light in a 2D plane, whereas a Point Light is a type of light source that emits light in all directions. In the context of this technique, a Light 2D is used to illuminate the sprite, whereas a Point Light would not be suitable.

Q: Can I use a different light source, such as a Spot Light?

A: Yes, you can use a different light source, such as a Spot Light, to illuminate the sprite. However, you would need to adjust the light source's settings to ensure that it is emitting light in the direction of the sprite.

Q: How do I configure the Light 2D to emit light in the direction of the sprite?

A: To configure the Light 2D to emit light in the direction of the sprite, you need to set the Light Direction property to the direction of the sprite. You can do this by selecting the sprite in the scene and then adjusting the Light Direction property in the Light 2D component.

Q: Can I use a different shader graph, such as a Standard Shader?

A: Yes, you can use a different shader graph, such as a Standard Shader, to render the sprite. However, you would need to adjust the shader graph's settings to ensure that it is working correctly with the Light 2D component.

Q: How do I troubleshoot issues with the sprite not being visible or hidden?

A: To troubleshoot issues with the sprite not being visible or hidden, you can try the following:

Make sure that the sprite is properly configured and that the light source is emitting light in the direction of the sprite.
Check that the shader graph is properly configured and that the inputs and outputs are correctly set up.
Try adjusting the light source's settings or the shader graph's settings to see if it resolves the issue.

Q: Can I add more features to the sprite, such as animation or physics?

A: Yes, you can add more features to the sprite, such as animation or physics. However, you would need to adjust the shader graph's settings and the sprite's configuration to ensure that it is working correctly with the additional features.

Q: How do I improve the performance of the sprite?

A: To improve the performance of the sprite, you can try the following:

Use a more efficient shader graph or optimize the code to reduce the number of calculations.
Use a lower-resolution texture or a more efficient texture format.
Use a different light source or adjust the light source's settings to reduce the number of calculations.

Conclusion

In this article, we have answered some of the most frequently asked questions about creating a sprite that is invisible when outside of a light source and visible when inside of it. We have covered topics such as using different light sources, configuring the light source, and troubleshooting issues with the sprite not being visible or hidden. We hope that this article has been helpful in answering your questions and providing you with a better understanding of this technique.

Tips and Variations

Use a different light source: Instead of using a Light 2D component, you can use a different light source such as a Point Light or a Spot Light.
Use a different shader graph: Instead of using a Custom Lit Shader Graph, you can use a different shader graph such as a Standard Shader or a Unlit Shader.
Add more features: You can add more features to the sprite such as animation, physics, or collision detection.

Common Issues and Solutions

Sprite is not visible: Make sure that the sprite is properly configured and that the light source is emitting light in the direction of the sprite.
Sprite is not hidden: Make sure that the sprite is properly configured and that the light source is not emitting light in the direction of the sprite.
Shader graph is not working: Make sure that the shader graph is properly configured and that the inputs and outputs are correctly set up.

Future Improvements

Add more features: You can add more features to the sprite such as animation, physics, or collision detection.
Improve performance: You can improve the performance of the sprite by using a more efficient shader graph or optimizing the code.
Add more customization options: You can add more customization options to the sprite such as different light sources, different shader graphs, or different materials.