I’ve made a material with a basic spiral blur to fake a DOF background blur for my project (it was causing glitches the regular way with camera DOF because my game is local coop splitscreen).
However, when it overlaps with my water material, it completely breaks it?
I have no idea why this is happening, the water is also set to a higher priority so I’m not sure what else to try to try sort this out??
yeh thats a classic translucent vs translucent problem, not your water settings. your blur plane samples the scene color buffer, and that buffer only holds the opaque stuff at the time translucency renders, so the water behind or in front of it gets drawn twice or not at all depending on order. sort priority only orders translucent against translucent, it doesnt fix what the scene texture contains.
the fix people use: mask the blur so it never touches water pixels. turn on render custom depth with stencil on the water mesh (set the custom depth-stencil pass to enabled with stencil in project settings), then in the blur material read the custom stencil and skip the blur where it is the water value, just output plain scene color there. there is a scene texture node for custom depth and a material flag to render the mesh into it, both in the details panel.
second thing to check is that your blur plane itself is translucent, so it adds overdraw on every tap of the spiral. keep the tap count low on splitscreen, that path gets expensive fast with two viewports rendering it. if the mask still shows an edge, push the blur plane slightly behind the water sort order so the water always draws last.
