Currently the default transparency setting for the rectange fill colour is set to 30. I'd like to add an API method for customizing this transparency value. The reason is that it is impossible to use a bright color roundbox indicator, such as yellow 0xFFFF00, as the colour is washed out by the transparency setting. Allowing a custom alpha value per indicator can resolve this issue (i.e. set to 100, no transparency).
Attached is a patch against the current scintilla CVS source to provide SCI_INDICSETALPHA, SCI_INDICGETALPHA API methods for setting this alpha transparency value.
Note: The rectangle border of the INDIC_ROUNDBOX is not changed and still uses an alpha transparency setting of 50.