Projected bounding-sphere area, drawing-buffer px, clipped to the buffer; 0 when off-screen.
Visible (committed) element count.
elements / max(areaPx, 1); 0 when off-screen.
Frame stamp of the last evaluation that saw this node.
Keep fraction the density guard currently applies to this node (1 = no
thinning). Written by scene/density-guard.ts; 1 until it runs.
Whether the node's blend mode sums energy (additive / luminous / volumetric). Written by the density guard; true until it runs, since the blendable cap is the more permissive one.
One node's projected footprint for the last evaluated frame.