# Objective
gpu based mesh uniform construction in the `GpuPreprocessNode` is
currently in `Core3d`. The node iterates all views and schedules the
uniform construction for each. so
- when there are multiple 3d cameras, it runs multiple times on each
view
- if a view wants to render meshes but doesn't use the `Core3d` graph,
the camera must run later than at least one `Core3d`-based camera (or
add the node to its own graph, duplicating the work)
- If views want to share mesh uniforms there is no way to avoid running
the preprocessing for every view
## Solution
- move the node to the top level of the rendergraph, before the camera
driver node
- make the `PreprocessBindGroup` `clone`able, and add a
`SkipGpuPreprocessing` component to allow opting out per view
e6b5270da2