The default studio environment's level-preserving mean of 1 acted like a
100% white Ambient light: with only the Environment light on, a white floor
rendered at full white (95% of the frame saturated) while its shadow core
went to pitch black — a fog over the scene, nothing like After Effects'
default. Three changes bring the look in line, CPU and GPU alike:
- The default environment is a dim studio now: a solid-angle-weighted mean
of 0.3 (and a stronger key gradient), so a white floor reads a mid gray
and the light's colour x intensity still scales the level.
- The shadow occludes only the image's directional (key) fraction of the
light — |sum of dir x radiance| / sum of radiance, computed beside the
dominant direction and carried in the scene — so the fill keeps shining
inside the shadow: an area-light shadow, partial like After Effects'
(a lone bright spot on black still shadows almost fully; a uniform image
not at all).
- The environment shadow map's penumbra has a floor — eight output pixels,
or four map texels where those are coarser — because the map covers the
whole scene bounding sphere rather than the view, and its texels would
otherwise stair-step the edge (all the more in a draft render's flat 512
budget). Shadow Diffusion widens it further, as before.
Tests: the key fraction tracks directionality; the default keeps its dim
level, its direction and its key; the default and a bright key both shadow
the floor (the default partial, the key deep) with Cast Shadows off lit
everywhere; and the full look — a mid-gray lit floor (no fog), a partial
core, and a soft edge ramp in quality and draft renders alike.
The Casts Shadows option Environment lights got is only half a fix if
nothing shades for it: an image lights the scene from every direction,
and what occludes that light is the image itself — its dominant bright
region, the sun in a sky map.
- dominant_direction finds it: the radiance-weighted mean texel
direction (solid-angle weighted, rotation applied). A uniform image
cancels to zero — a flat default environment shines from everywhere
at once and casts no shadow, which a uniform environment test pins.
- The shadow is one orthographic map over the scene from that
direction, after the lights' maps, like a parallel light's: PCF
widened by Shadow Diffusion, darkened by Shadow Darkness, cleared
when nothing casts, the image is directionless, or the texel budget
drops it.
- It darkens the environment's own diffuse and specular light on
Accepts Shadows surfaces and counts in Cast Shadows Only. CPU and
GPU (WGSL) do the same; Globals carries the environment's sun
direction and shadow settings (40 → 44 floats, preflight updated).
A bright-disc environment turned to shine from behind the camera now
shadows a sphere onto the floor behind it, Cast Shadows off lights it
evenly again, and the GPU scene's sky gradient takes a shadow-casting
Environment light. Also: the renderer-switch toasts read "...renderer,
which draws 3D models", the dialog's Casts Shadows checkbox gets an
auto id (dialog.light.casts) the tests click, and the docs' Environment
notes cover the shadow.
Shadow maps use the full scene-derived size (point-light faces capped
at 2048) under a 26M-texel scene budget halved largest-first; the PCF
filter measures its reach in output pixels with a two-texel minimum,
samples texel centres on a jittered adaptive 5..10 grid, and compares
each texel against the receiver plane's own depth so wide kernels never
self-shadow lit casters. The WGSL mirror is parenthesised (Tint rejects
the old form) and guarded by a shader-wide grammar test; the CPU
reference and shader remain step-for-step parity-tested.
The Advanced 3D renderer folded Accepts Shadows (Off/On/Only) into a
bool, so a shadow catcher set to Only drew as an ordinary lit surface.
The material now carries shadows_only. Such a fragment draws black at
the strongest shadow a light casts on it, as Classic 3D does, and it
goes in the blended pass so what is behind it shows through. The CPU
shader and advanced3d.wgsl get the same branch.
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
Extruded text keeps per-character 3D: each glyph's outline is extruded in its own space and
placed by its animated matrix; shape layers extrude their fill outlines (gradients use their
mid colour). Shadow-map bias scales with the texel footprint at the receiver and the PCF
reach (no acne on curved casters), identically on CPU and GPU. Docs: Advanced 3D in
architecture.md, parity table updated (3D, Text).
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Advanced 3D comps render their 3D runs as one scene of world-space triangles: model and
primitive layers (meshes, skinning, animation clips by layer time), extruded text/shape
layers, and textured cards for every other layer with their Material Options. Shading is
physically based in linear light: Cook-Torrance GGX + Lambert for parallel/spot/point lights
(AE falloff and cone), ambient lights, image-based light from an Environment light's layer
(equirectangular; cosine irradiance map + roughness mip chain + split-sum BRDF fit), and
PCF shadow maps (spot/parallel/point cube faces). 2x2 SSAA, depth of field as a gather blur
by circle of confusion, back to the working encoding.
The software rasteriser (depth buffer, top-left rule, perspective-correct, opaque visibility
then sorted transparent blending) is the reference and CI path; effectcraft-gpu implements
Accelerator::raster_3d with a wgpu render pipeline (advanced3d.wgsl) and matches it within
tolerance. Environment layers are hidden from both renderers.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Z User