When encountering a pink tint on materials in Unity, especially when using the Universal Render Pipeline (URP), it typically indicates a shader compatibility issue or a shader compilation error. Given that the issue persists across both 4.1 and 4.2 runtimes and specifically arises when using an Orthographic camera with the Universal Render Pipeline/Spine/Skeleton shader, it suggests that the shader may not be fully compatible with the Orthographic projection in the context of rendering to a RenderTexture.
To address shader compatibility issues with URP, especially when dealing with specific rendering features like Orthographic projection or RenderTexture outputs, it's crucial to ensure that the shaders are correctly set up for URP and that they support the intended rendering path (e.g., Forward Renderer). The Spine URP shaders are designed to work with the URP setup, but certain configurations or specific uses like rendering to a RenderTexture with an Orthographic camera might require additional considerations or adjustments.
Since the provided contexts do not directly address the issue of pink tint in RenderTexture outputs with Orthographic projection using URP, the best approach would be to verify that the shader is up to date and fully compatible with URP's requirements for rendering to textures. Additionally, checking for any known issues or updates related to shader compatibility with Orthographic projection in the Spine-Unity runtime documentation or the Spine URP shader package might provide further insights or solutions.
