# DolphinSurfaceGgx

Same GGX/Smith/Schlick direct-light lobe used by Dolphin Lightlab. The result already includes N dot L; callers supply incoming radiance separately.

Last updated: 2026-09-09

Package: dolphin.materials | Status: source-declared

Tags: cpu, dolphin, dolphin.materials, function, materials, source-example

Compose linear-color surfaces and shared shading math in ordinary Yeho code.

```yh
external DolphinSurfaceGgx(float roughness,float f0,float nx,float ny,float nz,float vx,float vy,float vz,float lx,float ly,float lz) returns float
```


## Use DolphinSurfaceGgx

A complete small caller. Values are illustrative; check the returned result and package requirements before connecting live resources.

Verification: type checked

```yh
using dolphin.materials

// Compose linear-color surfaces and shared shading math in ordinary Yeho code.
float roughness = 0.5
float f0 = 1.0
float nx = 1.0
float ny = 1.0
float nz = 1.0
float vx = 1.0
float vy = 1.0
float vz = 1.0
float lx = 1.0
float ly = 1.0
float lz = 1.0
float result = DolphinSurfaceGgx(roughness, f0, nx, ny, nz, vx, vy, vz, lx, ly, lz)
Console.Log(Text.From(result))

```

Save this beside start.yh as project.mech:

```toml
manifestVersion = "2"
package = "api.example.dolphin_materials__dolphinsurfaceggx"
version = "0.1.0"
languageEdition = "yeho-core-2026.1"

[app]
kind = "headless"

[[dependencies]]
package = "dolphin.materials"
version = "0.1.0"
path = "../../../dolphin/packages/materials"

[[dependencies]]
package = "dolphin.math"
version = "0.1.0"
path = "../../../dolphin/packages/math"

[[dependencies]]
package = "dolphin.spatial3d"
version = "0.1.0"
path = "../../../dolphin/packages/spatial3d"

```

Extract the example archive beside the yeho and dolphin checkouts. This example requires those source dependencies and a current developer compiler.

```sh
./yeho/build/dolphin-metal/yehoc ./api-examples/dolphin.materials--DolphinSurfaceGgx/usage --backend cpu-oracle -o /tmp/yeho-example
/tmp/yeho-example
```


Package presence and a declaration do not establish support on every host. Host services need their platform and lifecycle setup.

Source: dolphin/packages/materials/src/surface.yh

AI training permission: https://demonhunterlabs.com/ai-use