Image

Styles a responsive image: full-width, cover-fit, rounded corners with a themed placeholder background. Apply to an <img>.

alt is required (WCAG 1.1.1) and forwarded as the host's native alt attribute — pass decorative: true instead for a purely decorative image (alt="").

Props

Prop	Type	Default	Description
`alt`	`string`	— (required unless `decorative`)	Accessible text alternative.
`decorative`	`boolean`	`false`	Marks the image as pure decoration — renders `alt=""`.
`color`	`ValueOrState<ThemeColor>`	`"neutral"`	Placeholder background color tone.

Customization

Must see the source of patch at the bottom of each patch page to understand the structure then code it still code as html native element.

There are four levels of customization, in increasing order of effort:

Patch props. Each patch exposes a small, stable set of props—typically fewer than five. Lowest friction.
Context attributes. Use dataTone, dataSize, and dataDensity on a container to shift tone, size, or density for an entire subtree without touching individual elements.
Inline override. Native-wins merge strategy: any property set directly on the element overrides the patch value.
Create a variant. Clone a similar patch and edit it. Use this only when you need a reusable custom version.

Formulas

Unit - U = fontSize / 4 - convert final values with themeSpacing(n).

Size - n = intrinsic text lines, w = wrapping level, d = density factor:

height        = (n * 6 + 2 * d * w) * U
paddingBlock  = d * w * U
paddingInline = ceil(3 / w) * d * w * U
radius        = d * w * U

Base density d = 1.5:

U	w=0	w=1	w=2	w=3
height (`n = 1`)	6	9	12	15
paddingBlock	0	1.5	3	4.5
paddingInline	3	4.5	6	4.5
radius	0	1.5	3	4.5

Tone - K = N / 2 where N is the palette length. For N = 18, K = 9.

Role	Shift	n=0
Background	parent +/- n	0
Text	bg + K	6
Border	bg + K/2	3
Hover	bg + 2K/3	4
Selected / Focus	above +/- K/3	2-4

State shift range: K/3 <= delta <= 2K/3.

image

import { type PartialElement, toState, type ValueOrState } from "@domphy/core";
import { type ThemeColor, themeColor, themeSpacing } from "@domphy/theme";

type ImageProps = { color?: ValueOrState<ThemeColor> } & (
  | { alt: string; decorative?: false }
  | { decorative: true; alt?: undefined }
);

/**
 * Styles a responsive image: full-width, cover-fit, rounded corners with a
 * themed placeholder background. Apply to an `<img>` element.
 *
 * `alt` is a required prop (WCAG 1.1.1) forwarded onto the host as the native
 * `alt` attribute, not left for the call site to declare separately — a
 * native `alt` on the host element still wins over this if both are given
 * (Domphy's usual native-over-patch merge), but every call site must now
 * make an explicit choice. Pass `decorative: true` for `alt=""` (purely
 * decorative images the caller does not want announced).
 *
 * @hostTag img
 * @param props.alt - Accessible text alternative. Required unless `decorative: true`.
 * @param props.decorative - Marks the image as pure decoration — renders `alt=""` so assistive tech skips it. Optional.
 * @param props.color - Optional theme color tone for the placeholder background (`ValueOrState<ThemeColor>`). Defaults to `"neutral"`.
 * @example { img: null, src: "photo.jpg", $: [image({ alt: "A scenic mountain photo" })] }
 * @example { img: null, src: "divider.svg", $: [image({ decorative: true })] }
 */
function image(props: ImageProps): PartialElement {
  const color = toState(props.color ?? "neutral", "color");

  return {
    alt: props.decorative ? "" : props.alt,
    dataTone: "shift-2",
    _onInsert: (node) => {
      if (node.tagName !== "img") {
        console.warn(`"image" primitive patch must use img tag`);
      }
    },
    style: {
      display: "block",
      width: "100%",
      maxWidth: "100%",
      height: "auto",
      objectFit: "cover",
      borderRadius: themeSpacing(2),
      backgroundColor: (listener) =>
        themeColor(listener, "inherit", color.get(listener)),
      color: (listener) => themeColor(listener, "text", color.get(listener)),
    },
  };
}

export { image };

Image#

Props#

Image

Props