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A landscape page does not fit a portrait screen the right way up, so the device turns it: the page's width runs along the long side of the screen and the ink is written turned with it. The renderer draws that ink straight, which puts annotations sideways on every landscape document. Reported in ddvk#286. Worked out by plotting the raw stroke coordinates of a page into the screen's own 1404x1872 frame, where the handwriting reads sideways, and checked against the same page exported by the tablet itself. Turning it gives one uniform scale, the page width over the screen's long side: 0.5143 points per pixel across and 0.5146 down on a 960x540 page. On that page the tablet puts the ink at x 302.0..895.3, y 116.7 down from the top. With this it lands at x 302.7..894.0, y 117.3. The tablet grows the sheet to take in writing past the page edge, which is why its ink carries on past where this clips. pageTransform carries how a page is laid out rather than a bare scale, so the turned and unturned cases sit side by side instead of inside a ratio test. Portrait pages keep the scale they had.
This was referenced Sep 12, 2026
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Fixes #286, which has been open since January 2024.
A landscape page does not fit a portrait screen the right way up, so the device turns it a quarter turn: the page's width then runs along the long side of the screen, and the ink is written turned with it. The renderer draws that ink straight, so annotations on any landscape document come out sideways and mostly off the page.
The thread on #286 stalled on whether the firmware supported landscape at all. It does, and this is a renderer bug, not a device one.
How it was worked out
Plotting the raw stroke coordinates of a page into the screen's own 1404x1872 frame shows the handwriting reading sideways, which is the whole diagnosis. Turning it gives one uniform scale, the page width over the screen's long side: 0.5143 points per pixel across and 0.5146 down on a 960x540 page. Two axes agreeing to three decimal places is what says the model is right rather than fitted.
Checked against the same page exported by the tablet itself:
The tablet grows the sheet to take in writing past the page edge, which is why its ink carries on past where this clips.
The change
pageTransformcarries how a page is laid out rather than a bare scale, so the turned and unturned cases sit next to each other instead of inside a ratio test. Portrait pages keep exactly the scale they had, so nothing changes for them. The highlighter, which is drawn as one straight swipe, is flattened along whichever way the page runs.Something to know when you test this
Verifying it is harder than it should be because of #228: the exporter pairs the nth annotated page with background page n, rather than with the page the ink belongs to. On the 28 page document I used, page 8's ink is drawn over background page 3. So a landscape document will still look wrong after this change, for that separate reason. I measured the ink position rather than trusting the rendered page, which is why the numbers above are ink bounding boxes and not screenshots.
That second bug is not addressed here.