Vulkan has different depth limits then opengl. We fix this by retargetting the opengl limits into the limits that vulkan supports. This is done in the vertex shader, or in the geometry shader. When viewport index or layer isn't supported a geometry shader is added to workaround these missing features. In this case the depth range was could be done twice (vertex shader and geometry shader). Pull Request: https://projects.blender.org/blender/blender/pulls/126634