The flattener limited an image's resolution only by its total pixels, while
the renderer draws at most 32,768 pixels a side. A long area, such as a narrow
see-through gradient strip down a 2 m banner at 1200 ppi, came back cut off
at that length and was placed as if whole, so the rest of the strip was lost
in Flatten Transparency and in PDF/X-1a, PDF/X-3 and PDF 1.3 exports. The
resolution is now also limited by the longest side, as raster effects are.
- PDF/X-1a, PDF/X-3 and PDF 1.3 files leave the layers they don't print
out of the flattening. A flattened group no longer takes the place of
art in a layer that doesn't print, so the art of a clipping layer over
such a layer prints, and art of a layer that doesn't print stays out
of the file.
- A flattened group goes into a lower layer only when that layer prints,
shows and is a template as the clipping layer does, the clipping layer
and the groups it leaves have no opacity, blend mode or isolation, and
the clipping path has no fill. Otherwise the group holds only the art
inside the clipping layer, drawn over the clipping path's fill and the
art below, and the art below is flattened on its own. Before, the fill
covered the group, the group lost the layer's opacity, or the clipping
path cut the art below.
- Transparent art that a clipping path hides entirely, such as one of
area type holding only a space, is removed. Before, the export failed
because the art kept its transparency.
Object › Flatten Transparency follows the same rules. Documents without
clipping layers or layers that don't print export the same bytes as
before.
Flattening for PDF/X-1a, PDF/X-3, PDF 1.3 and EPS rasterized a picture,
gradient, pattern, mesh or raster effect over its whole frame when a
clipping mask cropped it. The hidden part came out as opaque white and
covered the art under it, on the same page and on the next one.
- Flattening rasterizes clipped art only where its clipping path shows
it, nested clip groups included.
- Art in a clipping layer is flattened as the layer's clipping path
shows it. A flattened group that also holds art from outside the
layer takes the place of that art, so the layer's clipping path no
longer cuts it.
Documents in which no clip group hides flattened art, and no clipping
layer holds it, export the same bytes as before.
Flatten Transparency composited each region over white, so a blend mode
on the bare page read that white. Raster renders now draw their
background under the finished art, and the flattened color no longer
matched them: a Color Burn object on the bare page flattened to white
and rendered in its own color. The region now composites the art alone
and puts the white under it.
- Tests that relied on the white under the art now draw art under the
style (`every_builtin_style_paints_visibly_on_a_rectangle`) or compare
only whole-pixel pans with a fresh render
(`a_coarser_glow_kept_whole_draws_after_a_pan_as_made_again`).
- New tests cover every blend mode on white and blue backgrounds, a
thumbnail and the ink planes with a Screen glow, and
`over_background` at background and pixel alpha 0, 128 and 255.
With an unclipped raster/vector balance between 0 and 100, a group that
splits into more than 10^(balance/20) regions is rasterized whole and
none of its regions are used. The region build now stops at the first
region past that limit (pathops `regions_within`) instead of building
every region and then discarding them. Groups at or under the limit,
and every group with Clip Complex Regions on, still build every region.
Flatten Transparency, the flattened document and EPS export come out
the same as with every region built, for groups under the limit, at it,
just over it and far over it.
A linked 1-bit image mask from a .ai file keeps its fill color as a
colorize paint, so the image takes the color once its file is relinked.
Until then the image shows the missing-link placeholder, and the canvas
and PDF export colorized that placeholder too: its light tile turned
nearly transparent and its red cross took the fill color.
ImageBlob::takes_colorize is false for a preview whose pixels are not
grayscale. While it is false, the canvas draws the image and PDF export
writes it as it is, printed separations separate it as an uncolorized
image, and transparency flattening (EPS, PDF 1.3 and PDF/X-1a export,
Flatten Transparency) does not count its paint as transparency. The
paint stays on the image, and a grayscale preview is still colorized.
SVG and EPS export already write only grayscale images colorized.
The overlap grouping swept left to right comparing each object's bounds
with every box still open at its left edge, so many objects sharing a
horizontal extent (stacked in a column) cost a comparison per pair
before any of the flattener's geometry limits applied, and the grouping
could not be cancelled.
Open boxes are now kept in a tree by their tops that knows the lowest
bottom below each branch, so each box meets only the open boxes it
overlaps; an open box inside a later box of its group, ending no further
right, is closed early. The grouping checks for cancellation as it goes.
Groups are unchanged: a test compares them with every-pair grouping.
EPS export expanded the pattern fills whose tile images need flattening and
then flattened the result with flatten_document, which expanded them again
with a new object limit. PostScript printing did the same, on the layers
shown rather than the layers that print. EPS export now flattens the
expanded document without expanding it again (flatten_expanded), and
PostScript printing leaves the expansion to the flattener, which runs on
the layers that print, and only checks for such pattern fills to warn.
Blends, envelopes, repeats and Intertwine groups that hold a see-through
or colorized pattern tile image are expanded into the art the writers
draw for them before the tiles are expanded, so those tiles are
flattened too. Random Transform effects in that art are baked first.
Hidden shapes, shapes in hidden groups or layers and template layers are
skipped: expanding a hidden shape made its tiles show in the file, and
art that is not written no longer makes a flattened copy of the document.
Flattening counted every colorized image as transparency, in the art and
in pattern tiles. A new flattener option, keeps_colorize, stops counting
an image colorized with a solid paint whose pixels are grayscale or 1-bit,
for a format whose writer draws such images in their ink. Opacity,
blending modes, opacity masks and effects still flatten them, and pattern
tiles are still expanded for those. The option is off, so exports flatten
as before; the EPS writer that draws colorized images turns it on.
The EPS pattern tile tests now check the exported colors, and a tile
group with opacity for the warning.
PDF 1.3, PDF/X-1a, PDF/X-3, EPS and PostScript printing flatten
transparency with `flatten_document`, which only looked at art in the
layers. An image with see-through pixels, a colorize paint, opacity or
a blending mode drawn only through a pattern fill stayed in the pattern
definition, so the flattener returned early and the writer drew the tile
opaque and uncolorized (PDF 1.3 export failed on the transparency left).
`flatten_document` now first expands pattern fills whose tile image
needs flattening into their tiles, as legacy .ai save does. See-through
tile pixels count only where the caller counts see-through images (PDF
1.3); EPS level 3 already masks them out. The EPS and PostScript print
transparency warnings now see those tile images too.
Follow-ups to the review of #4697 and #4698:
- With textAs: outlines, a .ai saved without PDF compatibility, read
from its editing data alone, has its type outlined too, as an empty
page or a text-only placeholder already did.
- Threaded type read from the editing data holds its story in its first
frame: it now flows through its frames before it is outlined, so each
frame's outlines show the text it holds, and the outlined frames
leave their threads.
- Each outline group keeps its type's opacity, blend mode, isolation,
opacity mask and effects (the same carry-over the flattener uses).
- A gradient-mesh corner (/N) holding anything but numbers is unread,
instead of being read with the numbers after it shifted into its
colour and opacity.
dotCooCoo