Security handlers manage encryption and decription of PDF files. The
standard security handler uses RC4/MD5 to perform its crypto (AES as
well, but that is not yet implemented).
This was a small optimization to allow a stream object to simply hold
a reference to the bytes in a PDF document rather than duplicating
them. However, as we move into features such as encryption, this
optimization does more harm than good. This can be revisited in the
future if necessary.
Incorrect is in quotes because the spec (both 1.7 and 2.0) specify this
multiplication as it was originally! However, flipping the order of
operations here makes the text in all of my test cases render in the
correct position.
The CTM is a transformation matrix between the text coordinate system
and the device coordinate system. However, being on the right-side of
the multiplication means that the CTM scale parameters don't have any
influence on the translation component of the left-side matrix. This
oddity is what originally led to me just trying this change to see if
it worked.
Previously, text spacing on a page would only look correct on very
zoomed-in pages. When the page was zoomed out, the spacing between
characters was very large. The cause for this was incorrect initial
values for the Tc (character spacing) and Tw (word spacing) text
parameters. The initial values were too large, but they were only
about 3-5 pixels, which is why the error was only observable for
smaller pages.
The text placement still isn't perfect, but it is _much_ better!
Apologies for the enormous commit, but I don't see a way to split this
up nicely. In the vast majority of cases it's a simple change. A few
extra places can use TRY instead of manual error checking though. :^)
This isn't a complete conversion to ErrorOr<void>, but a good chunk.
The end goal here is to propagate buffer allocation failures to the
caller, and allow the use of TRY() with formatting functions.
Add a check to `Parser::consume_eol` to ensure that there is more data
to read before actually consuming any data. Not checking if there is
data left leads to failing an assertion in case of e.g., a truncated
pdf file.
Same as Vector, ByteBuffer now also signals allocation failure by
returning an ENOMEM Error instead of a bool, allowing us to use the
TRY() and MUST() patterns.
