The CPU renderer's line depth test allowed a fixed share of the scene's depth range (2e-4), which on large designs or close views let edges a millimetre or more behind thin sheet show through it. Each pixel now keeps the screen depth slope of the surface it shows, and a line passes where it is no further behind than that slope spans across the line's width, plus f32 rounding. Section caps use their plane's slope.
Edges lying on steep faces now draw their full width; edges behind a face stay hidden. Only crates/render/src/raster.rs changes; the GPU viewport is unchanged.
Co-authored-by: NOWN-DEV <[email protected]>
