Unity Transparent Object. Looking at the same example Opaque Object Motion and Transparent Object Motion have not been explicitly disabled in the Main Camera’s Frame Settings override But since Motion Vector is disabled these dependent features are also turned off by the sanitization system as shown in Figure 4 Highlight B Volume system As discussed in our Unite Now talk.
By default the main camera in Unity renders its view to the screen More info See in Glossary Mode This allows you to choose whether the object uses transparency and if so which type of blending mode to use Opaque Is the default and suitable for normal solid objects with no transparent areas Cutout Allows you to create a transparent effect that has hard edges.
Unity Manual: Rendering Mode
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Using Transparent Material In Unity 3d Gyanendu Shekhar S Blog
Get acquainted with HDRP settings for blog.unity.com
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