pdfOptionalContentExtended · @awacloud/pdf — awaforge

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Extended OCG/OCMD — VE (Visibility Expression), Order tree, RBGroups, Intent — ISO 32000-2 §8.11.

Module pdfOptionalContentExtended | Source packages/front/office/pdf/src/extra/optional-content-extended.js | Deps pdfErrors, pdfParser | Worker-safe yes

§8.11.2.4 defines OCMD /VE (Visibility Expression) as a nested array [op, operand, …] with ops And, Or, Not. This module evaluates such expressions, types /Order (including sub-heading strings), and surfaces RBGroups and /Intent (View vs Design).

Resolve

const ext = runtime.resolve('pdfOptionalContentExtended');
// Returns: { evaluateVE, typeOrderTree, typeRBGroups,
//   classifyOcgIntent, VE_OPERATORS }

API

Member	Signature	Returns
`evaluateVE`	`(ve, onSet: Set<string>) => boolean`	Recursively evaluates; `onSet` holds `"num gen"` keys of "on" OCGs.
`typeOrderTree`	`(orderArray) => OrderNode[]`	Nodes shaped `{ kind: 'heading', text } \| { kind: 'group', children } \| { kind: 'ocg', ref } \| { kind: 'other', value }`.
`typeRBGroups`	`(arr) => Array<Array<{ num, gen }>>`	Mutually-exclusive radio-button groups.
`classifyOcgIntent`	`(value) => { view: boolean, design: boolean, names: string[] }`
`VE_OPERATORS`	frozen array	`['And','Or','Not']`.

Examples

Evaluate VE

const ext = runtime.resolve('pdfOptionalContentExtended');
const visible = ext.evaluateVE(
    { type: 'array', items: [
        { type: 'name', value: 'And' }, ocgRefA,
        { type: 'array', items: [{ type: 'name', value: 'Not' }, ocgRefB] }
    ] },
    onSet
);

Order tree

const tree = ext.typeOrderTree(orderArr);
// [ { kind: 'heading', text: 'Layer group' }, { kind: 'group', children: [...] }, … ]

Intent

ext.classifyOcgIntent({ type: 'name', value: 'View' });
// { view: true, design: false, names: ['View'] }

Errors

Code	Class	When
`pdf/extra/ocgx/ve/null`	`ParseError`	VE expression is null.
`pdf/extra/ocgx/ve/bad-state`	`ParseError`	`onSet` is not a `Set`.
`pdf/extra/ocgx/ve/bad-shape`	`ParseError`	Neither an array nor a ref.
`pdf/extra/ocgx/ve/bad-op`	`ParseError`	Operator outside `VE_OPERATORS`.
`pdf/extra/ocgx/ve/not-arity`	`ParseError`	Wrong arity (`Not` = 1, `And`/`Or` ≥ 1).
`pdf/extra/ocgx/order/not-array`	`ParseError`	`/Order` is not an array.
`pdf/extra/ocgx/rbg/not-array`	`ParseError`	`/RBGroups` is not an array.
`pdf/extra/ocgx/rbg/bad-group`	`ParseError`	A group entry is not an array.
`pdf/extra/ocgx/intent/bad`	`ParseError`	Intent is neither a name nor an array.

See also