Guide: Adding Emissive Photos in VR within Unity3D #

In this guide, we will demonstrate how to add emissive photos in virtual reality (VR) inside Unity3D. Emissive materials are crucial in VR environments, as they enable objects to emit light and improve the overall visual experience. We will provide step-by-step instructions to create an emissive material in Unity3D, discuss some use cases, and offer troubleshooting tips. This guide is designed for professional developers and is appropriate for inclusion in a wiki or technical documentation.

Creating Emissive Photos Using the Scriptable Render Pipeline (SRP) #

If you are using a custom Scriptable Render Pipeline (SRP) in Unity, you may need to create an emissive material specifically tailored to your pipeline. Below are general guidelines for implementing emissive materials in a custom SRP. Note that specific implementations may vary depending on your pipeline setup.

1. First, ensure that your SRP is set up correctly in your Unity project. The instructions for setting up an SRP can be found in the official Unity documentation.
2. Create a new shader file (.shader) for your emissive material within the custom SRP. The shader file should include both vertex and fragment shader functions to define the emissive material’s behavior.
3. In the shader file, set up the required properties for your emissive material, such as the texture, emissive strength, and color. These properties will be exposed in the Unity editor to allow for easy customization.

cCopy codeShader "Custom/EmissiveMaterial" {
    Properties {
        _MainTex ("Main Texture", 2D) = "white" {}
        _Emission ("Emission", Range(0, 1)) = 1
        _EmissionColor ("Emission Color", Color) = (1, 1, 1, 1)
    }
    ...
}

4. In the fragment shader function, multiply the texture’s color with the emissive color and strength to create the emissive effect. Then, output the final color to the screen.

cCopy codefixed4 frag(v2f i) : SV_Target {
    fixed4 col = tex2D(_MainTex, i.uv);
    col.rgb *= _EmissionColor.rgb * _Emission;
    return col;
}

5. Save the shader file and create a new material in Unity. Set the material’s shader to the custom emissive shader you just created.
6. Assign the texture you want to use for the emissive material to the “_MainTex” property in the material. Adjust the “_Emission” and “_EmissionColor” properties as desired to control the emissive strength and color.
7. Apply the material to a 3D object in your scene.

Note: The above instructions are for creating a basic emissive material in a custom SRP. Depending on your SRP setup and requirements, you may need to modify the shader code or material properties accordingly.

By following these instructions, you should be able to create emissive materials in a custom Scriptable Render Pipeline within Unity3D. Remember to test and adjust the settings to achieve the desired visual result in your specific project.

Creating Emissive Photos Using the Universal Render Pipeline (URP) #

Follow these steps to create a new emissive material in Unity3D URP:

1. Create a new material in Unity3D URP.
2. Change the material’s shader to “Unlit/Texture.”
3. Drag and drop the image you want to use as the picture onto the “Main Texture” field in the material.
4. Set the “Emission” value to 1 in the material’s properties. This will make the material emit light, ensuring the image appears clear, regardless of lighting conditions.
5. Apply the material to a quad or another 3D object in your scene.

Note: As an alternative, you can use the ‘Unlit’ standard shader for your pipeline to achieve the same desired effect.

Creating Emissive Photos Using Shader Graph #

For those looking to create custom effects or use their own shader, follow these instructions to achieve the emissive effect with Shader Graph:

1. Create a new material and open the Shader Graph window.
2. Create a new “PBR Master” node and connect it to the “Material Output” node.
3. Create a new “Texture 2D” node and connect it to the “Base Color” input of the “PBR Master” node. This will serve as the texture for the emissive material.
4. Create a new “Constant” node set to 1 and connect it to the “Emission” input of the “PBR Master” node. This will make the material emit light.
5. Create a new “Constant” node set to 1 and connect it to the “Metallic” input of the “PBR Master” node.
6. Create a new “Constant” node set to 0 and connect it to the “Smoothness” input of the “PBR Master” node.
7. Create a new “Constant” node set to 1 and connect it to the “Opacity” input of the “PBR Master” node. This will make the material fully opaque.
8. Click on “Apply” to finalize your custom shader.

Note: In Unity3D Shader Graph, emission is represented by a scalar value. You can control the emissive strength by changing the constant value connected to the emissive input.

Use Cases #

Emissive materials are useful in various VR applications, such as:

1. Immersive environments: Enhancing the realism and atmosphere of virtual environments, such as nighttime scenes, with self-illuminating objects like streetlights or neon signs.
2. User interfaces (UI): Creating glowing UI elements that are easily visible and attractive to users, improving overall usability and user experience.
3. Visual storytelling: Directing the user’s attention to specific elements or guiding them through a narrative using light sources.
4. Artistic effects: Adding a unique visual style to a VR experience through the creative use of emissive materials and lighting.

Troubleshooting #

If you encounter issues when creating emissive photos in Unity3D, consider the following troubleshooting tips:

1. Ensure your Unity project is using the correct render pipeline (URP or HDRP).
2. Verify that the emissive material’s texture is set up correctly and
3. connected to the appropriate input in the shader. 3. Check the scene’s lighting settings to ensure that they do not interfere with the emissive materials’ visibility or appearance.
4. If using a custom shader, double-check the connections between nodes in the Shader Graph and confirm that the values for the constants are set correctly.
5. Ensure that the 3D object you’re applying the emissive material to has UV coordinates properly set up to display the texture correctly.
6. Make sure that the camera’s settings, such as exposure or post-processing effects, do not adversely affect the appearance of the emissive materials.

Additional Tips for a Professional Guide #

To create a more comprehensive and professional guide, consider including the following sections:

1. Introduction: Briefly describe the purpose of the guide, its target audience, and the benefits of following the instructions provided.
2. Prerequisites: Outline any necessary tools, software, or knowledge that the user should possess before attempting the guide.
3. Version Information: Clearly state the Unity version and any other relevant software or plugin versions used in the guide.
4. Advanced Techniques: Provide additional instructions for users interested in advanced features, such as customizing emission colors, animating emissive materials, or using real-time GI with emissive materials.
5. Performance Optimization: Offer suggestions on optimizing the performance of emissive materials for better frame rates and lower resource consumption, particularly for mobile or standalone VR devices.
6. Conclusion: Summarize the guide’s main points and encourage users to experiment with emissive materials in their projects.

By incorporating these additional elements, you will create a more robust and professional resource that caters to a wide range of users and enhances the overall learning experience.