For now it's just possible to create a single pdf in selecting some pages in different pdf sources.
The merge is for now pretty basic (it's why it's still a WIP) none of these data are merged for now:
- the struct trees
- the page labels
- the outlines
- named destinations
For there are 2 new ref tests where some new pdfs are created: one with some extracted pages and an other
one (encrypted) which is just rewritten.
The ref images are generated from the original pdfs in selecting the page we want and the new images are
taken from the generated pdfs.
It'll help to make math equations "visible" for screen readers.
MS Office has a specific way to add some MathML code to struc tree leaf
and this patch handles it.
It fixes#20065.
The only to get a path (from the path generator) is when the font is embedded.
So when we need a path (disableFontFace: true or when we want to use a pattern for stroking/filling), it's impossible
to fulfil.
Necessary because when there is no Popup annotation created along
with a Text annotation, the Popup annotation created by pdf.js
does not receive the noRotate flag
The shadow was taken into account when computing the bounding box of the section
containing the link and it was making the clip path wrong.
Since the shadow is almost invisible because of the opacity, the yellow color and the clip
we can remove it without causing any visual regressions (and as a side effect it'll avoid
to use resources to compute it when displayed).
For simplicity we will abort /Form XObject parsing *immediately* when encountering a circular reference, rather than letting it continue up until some limit (as e.g. PDFium appears to do), which should be fine since there are never any guarantees if/how *corrupt* PDF documents will render.
Previously we'd only do this for Type1/CFF fonts, see e.g. PR 6736, since the font-program may update the /FontMatrix.
However, it seems that we should do this unconditionally to account for fonts with non-default /FontMatrix-entries in the font-dictionary (which seem to be pretty rare).
In PDF version 2.0 the handling of Indexed color spaces was clarified as follows:
> The index value should be an integer in the range 0 to hival. If the value is a real number, it shall be rounded to the nearest integer (0.5 values shall be rounded up); if it is outside the range 0 to hival, it shall be adjusted to the nearest value within that range.
Please refer to https://github.com/pdf-association/pdf-differences/tree/main/IndexedColor
The current text layer approach based on absolutely positioned
`<span>` elements by default causes flickering with text selection,
and we have browser-specific workarounds to solve that.
In Chrome, the workaround involves moving the `.endOfContent` element to
right after the last element that contains some selected content. This
works well in simple PDFs, but breaks when we have `span.markedContent`
elements. Given a text layer structure like the following, rendered
as four consecutive lines:
```html
<span class="markedContent">
<br>
<span>development enter the construction phase (estimated at around</span>
</span>
<span class="markedContent">
<br>
<span>300 MEUR).</span>
</span>
<span class="markedContent">
<br>
<span>Kreate's EBITA increased to 2.8 MEUR (Q4'23: 2.7 MEUR) and the</span>
</span>
<span class="markedContent">
<br>
<span>margin rose to 3.7% (Q4'23: 3.4%). However, profitability was</span>
</span>
```
when starting to select from inside the first line and dragging down
to the empty space after the second line, Chrome will anchor the
selection at the beginning of either the `<br>` or the `<span>` inside
the last `.markedContent`, depending on whether the selection is in
"per-character mode" (i.e. click and drag) or "per-word mode" (i.e.
double click and drag). This causes us to insert the `.endOfContent`
element in the wrong place (one element too far), which causes one
more line to be selected, which triggers another `"selecctionchange"`
event, which causes us to move `.endOfContent` again, and so on, looping
until when the whole page is selected.
This commit fixes the issue by making sure that when the end of the
selection range points to the _begining_ of an element, we walk back
the dom finding the first non-empty element, and attatch `.endOfContent`
to the end of that.
In the included PDF document the Type3-font doesn't contain any glyph definition for "space", despite that character being referenced in the /Contents stream.
While missing Type3-glyphs obviously cannot be rendered, we still need to update the current canvas position such that any char/word-spacing is correctly applied.
The test-case was found at https://github.com/pdf-association/pdf-differences/tree/main/Type3WordSpacing
This patch extends the approach of PR 14543, by also treating e.g. minus signs followed by '(' or '<' as zero.
Inside of a /Contents stream those characters will generally mean the start of one or more glyphs.
When rendering big PDF pages at high zoom levels, we currently fall back
to CSS zoom to avoid rendering canvases with too many pixels. This
causes zoomed in PDF to look blurry, and the text to be potentially
unreadable.
This commit adds support for rendering _part_ of a page (called
`PDFPageDetailView` in the code), so that we can render portion of a
page in a smaller canvas without hiting the maximun canvas size limit.
Specifically, we render an area of that page that is slightly larger
than the area that is visible on the screen (100% larger in each
direction, unless we have to limit it due to the maximum canvas size).
As the user scrolls around the page, we re-render a new area centered
around what is currently visible.
