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The shadow-mapped path's penumbra width was a fixed per-cascade value (shadow_smoothness_scale()'s ceiling), so every occluder blurred its shadow by the same amount regardless of how close it actually was to the receiver -- unlike the raytraced path, which gets that for free from traceShadowRayCone()'s real occluder distance. Close that gap with PCSS: search nearby texels for occluders, then scale the filter radius by how far away they were. The blocker search (pcssBlockerSearch() in shadows.sdr) needs raw, uncompared depth reads, which the existing PCF sampler can't do -- it's bound with a compare mode for the hardware shadow-compare instructions the filtered sampling itself relies on. So shadow maps now get a second sampler, shadow_map_raw, bound to the same texture with compare mode off; on OpenGL that needs a second sampler object and GL 3.3 (shadow_contact_hardening_supported()), Vulkan can always bind it. Where the raw sampler isn't available, or the new Graphics.ShadowContactHardening option is off, shadows_start_render() sets Shadow_penumbra_scale[cascade] to -1 as a sentinel and pcssPenumbraRadius() (shadows.sdr) falls straight back to the fixed radius, bit-identical to the pre-contact-hardening behavior and skipping the extra texture reads. When it is on, shadows_start_render() computes each cascade's penumbra scale from its own frustum extents and the sun's tanθ; the shader turns that plus the blocker search's average depth into a per-pixel radius, clamped to [1 texel, the old fixed ceiling]. A blocker search that finds nothing doesn't fall back to "no shadow" -- a sparse 8-tap search can miss a thin occluder, so it instead runs the full filter at the hardest (1-texel) radius, trading a touch of extra blur for not popping a real shadow to nothing. Drops RT_SHADOW_SUN_SIZE_CALIBRATION accordingly: that constant existed only to fake a blocker-distance-driven penumbra on the shadow-mapped path by pre-scaling the raytraced cone to match it, and the shadow-mapped path now has a real blocker search of its own, so the raytraced cone goes back to its physically correct size.