Reference

Presets

Seven looks from grasspro.html, one file each in src/config/presets/. Hover a card to see the wind move the field, click to enlarge it, or run one live.

Meadow preset — Meadow`meadow`Mid-morning spring grass, light fog, a scatter of flowers.

Golden Hour preset — Golden Hour`golden`Low sun at 17:36 behind the blades, stronger translucency.

Windy Hills preset — Windy Hills`windy`Tall grass on steep hills, strong gusts and gust sheen.

Wildflowers preset — Wildflowers`wildflowers`Short lush grass with the flower layer at full amount.

Autumn preset — Autumn`autumn`Russet grass, orange leaves and falling-leaf drift.

Dry Savanna preset — Dry Savanna`savanna`Sparse, clumped dry grass, warm haze and flat acacias.

Night Fireflies preset — Night Fireflies`night`22:30 under the moon, with fireflies over the field.

#Loading presets

grass.loadPreset('golden');              // by name
grass.loadPreset(JSON.parse(savedJson)); // or a preset object, e.g. copied from the demo

loadPreset() applies the grass and wind sections at once. There is no easing. create({ preset }) does the same at start-up, and defaults to 'meadow'.

#Presets are plain data

src/config/presets/golden.js

/** @type {import('./index.js').GrassPreset} */
export default {
  label: 'Golden Hour',
  grass: { density: 1, height: 1.1, width: 1, season: 0.3, clumping: 0.5, translucency: 1.2, specular: 1, gustSheen: 1 },
  wind: { speed: 0.35, gust: 0.5, direction: 200 },
  scatter: { flowers: 0.2 },
  environment: { time: 17.6, hills: 1, fog: 0.008, haze: 0, drift: 1, fireflies: false, savanna: false, camera: [-4.5, 1.8, -6.5] },
};

Section	Used by
`grass`	`GrassSystem`: see Grass parameters
`wind`	The grass's `WindField`
`scatter`	A suggested flower amount. Your app applies it, for example with `flowers.setAmount()`
`environment`	Staging hints for the demo: time of day, hill height, fog, haze, leaf drift, fireflies, savanna trees and the camera offset. The library ignores it

getParams() keeps the scatter and environment sections of the last loaded preset, so a preset round-trips through loadPreset() and getParams() unchanged.

import { PRESETS, getPresetParams } from 'naturegl-grass';

Object.keys(PRESETS);           // ['meadow', 'golden', 'windy', 'wildflowers', 'autumn', 'savanna', 'night']
getPresetParams('savanna');     // deep clone; throws on an unknown name

#Try one live

Starts on `windy`. Press 1–7 in the demo to switch presets.

#Reference

Name	Label	Density	Height	Wind	Gust	Season	Demo staging
`meadow`	Meadow	1.0	1.0	0.55	0.6	0.12	10:30, light fog, some flowers
`golden`	Golden Hour	1.0	1.1	0.35	0.5	0.30	17:36, back-lit, translucency 1.2
`windy`	Windy Hills	1.0	1.4	1.6	1.2	0.08	14:00, hills × 2.1, gust sheen 1.4
`wildflowers`	Wildflowers	0.9	0.85	0.45	0.5	0.02	11:30, flowers amount 1.0
`autumn`	Autumn	0.95	0.9	0.75	0.8	0.60	15:30, falling leaves
`savanna`	Dry Savanna	0.72	1.35	0.6	0.6	1.00	16:24, clumping 0.85, warm haze, flat acacias
`night`	Night Fireflies	1.0	1.0	0.3	0.35	0.18	22:30, fireflies