AnyImage/openspec/changes/archive/2026-09-17-scale-tangent-normals-with-depth/specs/depth-scaled-tangent-normals/spec.md at 531f7a4dfb212816f50241c909e5ec3cfe8ece62

Files

nan 076a8c90f1 Add specifications for two-times upscale and unified depth plane features

- Introduced the two-times upscale specification detailing requirements for unified output, fixed model presets, arbitrary dimensions, and consistent job behavior.
- Added scenarios for existing models, repeated upscale, and handling of alpha preservation.
- Created the unified depth plane specification outlining geometry modes, stable interface, and asset evaluation.
- Defined scenarios for mode switching, relief and camera preservation, and validation of delivered assets.

2026-09-17 17:19:05 +08:00

1.9 KiB

Raw Blame History

ADDED Requirements

Requirement: Normal strength follows geometry depth scale

When a Geometry Nodes group both exposes Depth Scale and is rendered with a normal map, it SHALL store 1 - Depth Scale as the o_normal_reduction float attribute on its final geometry. O Image Layer SHALL calculate Tangent and Object Normal Map Strength as its Normal Scale input multiplied by 1 - o_normal_reduction.

Scenario: Reduced relief depth reduces Tangent normal strength

WHEN an O Image Relief Plane uses a Tangent normal map and Depth Scale is set to 0.5
THEN the Tangent Normal Map Strength is one half of the value produced at Depth Scale 1 with the same Normal Scale input

Scenario: Zero relief depth disables Tangent normal detail

WHEN an O Image Relief Plane uses a Tangent normal map and Depth Scale is set to 0
THEN the Tangent Normal Map Strength is zero

Scenario: Depth extrapolation is preserved

WHEN an eligible Tangent-normal geometry group uses Depth Scale greater than 1
THEN o_normal_reduction is negative by the corresponding amount and the Tangent Normal Map Strength retains the extrapolated value without clamping

Requirement: Reduction attribute retains its material fallback

O Image Layer SHALL use a factor of 1 for its Tangent Normal Map Strength when o_normal_reduction is absent. The existing o_normal_reduction material contract SHALL remain unchanged.

Scenario: Ordinary image material has no normal-scale attribute

WHEN an object using O Image Layer has no o_normal_reduction attribute
THEN its Tangent Normal Map Strength equals the Normal Scale input

Scenario: Object Space normal strength follows the reduction

WHEN O Image Layer is configured for an Object Space normal map and its geometry has any o_normal_reduction value
THEN the Object Space Normal Map Strength equals the Normal Scale input multiplied by 1 - o_normal_reduction

1.9 KiB Raw Blame History