[api-minor] Extend general transfer function support to browsers without OffscreenCanvas

This patch extends PR 16115 to work in all browsers, regardless of their `OffscreenCanvas` support, such that transfer functions will be applied to general rendering (and not just image data).
In order to do this we introduce the `BaseFilterFactory` that is then extended in browsers/Node.js environments, similar to all the other factories used in the API, such that we always have the necessary factory available in `src/display/canvas.js`.

These changes help simplify the existing `putBinaryImageData` function, and the new method can easily be stubbed-out in the Firefox PDF Viewer.

*Please note:* This patch removes the old *partial* transfer function support, which only applied to image data, from Node.js environments since the `node-canvas` package currently doesn't support filters. However, this should hopefully be fine given that:
 - Transfer functions are not very commonly used in PDF documents.
 - Browsers in general, and Firefox in particular, are the *primary* development target for the PDF.js library.
 - The FAQ only lists Node.js as *mostly* supported, see https://github.com/mozilla/pdf.js/wiki/Frequently-Asked-Questions#faq-support
This commit is contained in:
Jonas Jenwald 2023-03-12 15:47:01 +01:00
parent 945855a2b8
commit fc055dbd80
8 changed files with 92 additions and 102 deletions

View file

@ -16,6 +16,7 @@
import {
BaseCanvasFactory,
BaseCMapReaderFactory,
BaseFilterFactory,
BaseStandardFontDataFactory,
BaseSVGFactory,
} from "./base_factory.js";
@ -48,7 +49,7 @@ class PixelsPerInch {
* an image without the need to apply them on the pixel arrays: the renderer
* does the magic for us.
*/
class FilterFactory {
class DOMFilterFactory extends BaseFilterFactory {
#_cache;
#_defs;
@ -60,6 +61,7 @@ class FilterFactory {
#id = 0;
constructor({ docId, ownerDocument = globalThis.document } = {}) {
super();
this.#docId = docId;
this.#document = ownerDocument;
}
@ -823,9 +825,9 @@ export {
deprecated,
DOMCanvasFactory,
DOMCMapReaderFactory,
DOMFilterFactory,
DOMStandardFontDataFactory,
DOMSVGFactory,
FilterFactory,
getColorValues,
getCurrentTransform,
getCurrentTransformInverse,