diff options
| author | Rodrigo Arias Mallo <rodarima@gmail.com> | 2025-09-28 20:26:15 +0200 |
|---|---|---|
| committer | Rodrigo <rodarima@gmail.com> | 2025-09-28 23:10:55 +0200 |
| commit | fb510ea86be5ceb9e91573890242581fdbd77ad8 (patch) | |
| tree | d819fe40683592008d136727f5a0b03e48dc1164 /359/index.md | |
Diffstat (limited to '359/index.md')
| -rw-r--r-- | 359/index.md | 74 |
1 files changed, 74 insertions, 0 deletions
diff --git a/359/index.md b/359/index.md new file mode 100644 index 0000000..35d9ba5 --- /dev/null +++ b/359/index.md @@ -0,0 +1,74 @@ +Title: Text under scrollbar when placed on the left side +Author: rodarima +Created: Thu, 27 Feb 2025 21:28:01 +0000 +State: closed + +Reproducer: https://emreed.net/LowTech_Directory + + + +--%-- +From: rodarima +Date: Thu, 27 Feb 2025 21:37:19 +0000 + +Simplified reproducer: + +```html +<!DOCTYPE html> +<html> + <head> + <title>Test text under left scrollbar</title> + <style> + body { width: 700px; height: 1000px; } + </style> + </head> + <body> + <p> + Can you read me? + <em>You must set the scrollbar_on_left=YES config option</em> + </p> + </body> +</html> +``` + +--%-- +From: rodarima +Date: Thu, 27 Feb 2025 22:25:58 +0000 + +Ah, I see. We first perform the layouting in one go, assuming the scrollbar is not needed and placing the content closer to the window border. Then the canvas ascent and descent is updated, triggering Layout::containerSizeChanged: + +https://github.com/dillo-browser/dillo/blob/fbd719f93ab659fec6c42952e76f5e5b971728be/dw/layout.cc#L966-L972 + +https://github.com/dillo-browser/dillo/blob/fbd719f93ab659fec6c42952e76f5e5b971728be/dw/layout.cc#L1344-L1354 + +But this in turn never enters again inside the conditional: + +https://github.com/dillo-browser/dillo/blob/fbd719f93ab659fec6c42952e76f5e5b971728be/dw/layout.cc#L928-L929 + +So the allocation.x is never updated: + +https://github.com/dillo-browser/dillo/blob/fbd719f93ab659fec6c42952e76f5e5b971728be/dw/layout.cc#L947-L948 + +We cannot apply this optimization: + +https://github.com/dillo-browser/dillo/blob/fbd719f93ab659fec6c42952e76f5e5b971728be/dw/layout.cc#L925-L929 + +As otherwise we will miss the case in which the canvas it too large when the toplevel widget has finished rendering. We need to trigger a toplevel resize as if the viewport has changed its size. + +--%-- +From: rodarima +Date: Thu, 27 Feb 2025 23:02:51 +0000 + +The toplevel widget will refuse to queue a resize if its own size is specified in absolute units: + +https://github.com/dillo-browser/dillo/blob/fbd719f93ab659fec6c42952e76f5e5b971728be/dw/widget.cc#L456-L460 + +This is actually correct, as the size of the widget won't change. We only need to force the top level widget to re-allocate (compute the position of the tree in a different offset). We can just enable the NEEDS_ALLOCATE flag when we detect that the scrollbar was just enabled. + +--%-- +From: rodarima +Date: Thu, 27 Feb 2025 23:04:41 +0000 + +That seems to fix it. I will need to check we don't accidentally enter a loop of allocations, but it doesn't seem posible. It will trigger the emergency brake anyway. + +
\ No newline at end of file |