#2173 SciTE do not show the underscore with gtk-3.24.18

[Pierre Biava]

Hello,
I have been using the scintilla plug-in for many years as an editor for Anjuta. Since my transition to Ubuntu 20.04 and gnome 3.36 (gtk-3.24.18 instead of 3.24.12) the underscores no longer appear in the text as in this example: gsb_data_transaction_save_transaction_pointer () ->
gsb datatransaction save transaction pointer ().I see the underscore when i select the line.
I installed the SciTE version 4.3.3 and I have the same thing.
Is this a known bug?

[Neil Hodgson]

Something has changed with font measurements in Ubuntu 20.04 leading to this issue. The height and other measurements of fonts are floating point numbers. To ensure each line is independent, these are converted to an integral number of pixels. For Sans 9 point on Ubuntu 20.04, the ascent is 11.1 pixels and the descent 2.8 pixels. In previous releases, converting to the next lowest integer (floor) has resulted in a generally good appearance with no excessive space but with character extremities (such as underscores) still visible.

There are several work-arounds:

1. Turn on multi-phase drawing with SCI_SETPHASESDRAW(SC_PHASES_MULTIPLE). This allows lines to share pixels but is slow on GTK.
2. Add an extra pixel of descent with SCI_SETEXTRADESCENT(1).
3. Choose font sizes that have just over an integral pixel descent such as Sans 9.55 point. Serif and DejaVu Sans Mono also work OK at 9.55 point.

The conversion to integer may change in a future release to use round.

[Pierre Biava]

Thank you for the quick reply.
I tried the first two solutions without success. After recompiling the plugin, the underscores are still not visible.
I had more luck with the third method which works systematically with the Free_mono font and for several sizes for the others. For example Ubuntu Regular 12,13 ..

[Neil Hodgson]

A potential fix was committed as [69ebdf]. This may not solve every case but it should help in most.

[Neil Hodgson]

A potential fix was committed as [69ebdf]. This may not solve every case but it should help in most.