The software scaling code expects this pointer to already be offset
by `src_x` and `src_y` but this function copied a pointer only
offset by the image offset, forgetting about instance offset.
Previously both the padding and clip rect calculations didn't take into
account zoom (negative margins) which resulted in more or less broken
behavior depending on if `sub-use-margins` was set or not.
This fixes those to properly handle negative margins which:
- Makes us calculate a tighter clip rect if `!sub-use-margins`.
- Unbreaks layout zoomed in and `sub-use-margins`.
Previously this function would just count bytes which was very easily
broken by incantations like `Ő̶̧͍̹͔̮̮̦͌̈̌̂́̊͜K͖̮̼̯͖͆͋̓̀̕` which take up 52 bytes while being just
2 normal width characters visually.
`terminal_display_width` correctly counts `Ő̶̧͍̹͔̮̮̦͌̈̌̂́̊͜K͖̮̼̯͖͆͋̓̀̕` as 2 visual characters.
Note: GitHub strips all these in their web UI but there are many Unicode
combining characters after each letter of the `OK`s above that produce
a "cursed" text effect.
Fixes#17772
The language hint is required for *correct* handling of RTL in srv3 so
provide the best-effort guess from the subtitle track.
Without this hint some RTL paragraphs are going to be wrongly assumed
LTR and reorder incorrectly. Additionally, subrandr may soon start
treating srv3 segments as `inline-block`s which means guessing is not
going to be possible anymore (at least as part of unicode bidi algorithm).
The instanced API allows a lot of work to be offloaded to the GPU and
makes software rasterization tolerable performance-wise in most cases.
This is similar to sd_ass but there are some substantial differences:
- It uses a BGRA atlas to allow drawing bitmap emoji.
- De-duplicates images internally to significantly reduce atlas size by
reusing the same atlas image for different instances.
- Exploits bilinear interpolation to further reduce atlas size of some
primitives. For example this allows reducing background boxes to one
very stretched pixel.
Bumps subrandr requirement to `v1.1` since this API is not present in
earlier versions.
subrandr is a subtitle rendering library which aims to render
SRV3 (YouTube) subtitles and WebVTT subtitles accurately.
Currently in mpv WebVTT subs are rendered via ffmpeg conversion to ASS
which throws away a lot of the style and completely disregards
the WebVTT non-region-cue positioning algorithm. Furthermore if
one wants to render some more complex SRV3 subtitles one has to
resort to external converters since it's not even supported by ffmpeg.
However subrandr is able to render SRV3 subtitles natively with support
for the most commonly used features. It can render ruby text without
relying on font metrics during conversion which is obviously fragile,
and it can perform correct scaling using the exact calculations used by
YouTube instead of making up ASS approximations. Similarly it follows
the WebVTT spec for the features of WebVTT that it supports (mostly).
It's not perfect of course and there's still many things it doesn't do
or does wrong but those are things that can be incrementally improved
outside of mpv.
Hubert Głuchowski