diff options
Diffstat (limited to 'macosx')
| -rw-r--r-- | macosx/tkMacOSXScrlbr.c | 12 |
1 files changed, 10 insertions, 2 deletions
diff --git a/macosx/tkMacOSXScrlbr.c b/macosx/tkMacOSXScrlbr.c index 66619c2..dff6cc9 100644 --- a/macosx/tkMacOSXScrlbr.c +++ b/macosx/tkMacOSXScrlbr.c @@ -214,12 +214,20 @@ static void drawMacScrollbar( CGContextStrokeLineSegments(context, outer, 2); /* - * Do not display the thumb unless scrolling is possible. + * Do not display the thumb unless scrolling is possible, in accordance + * with macOS behavior. + * + * Native scrollbars and Ttk scrollbars are always 15 pixels wide, but we + * allow Tk scrollbars to have any width, even if it looks bad. To prevent + * sporadic assertion errors when drawing skinny thumbs we must make sure + * the radius is at most half the width. */ if (scrollPtr->firstFraction > 0.0 || scrollPtr->lastFraction < 1.0) { CGRect thumbBounds = {thumbOrigin, thumbSize}; - path = CGPathCreateWithRoundedRect(thumbBounds, 4, 4, NULL); + int width = scrollPtr->vertical ? thumbSize.width : thumbSize.height; + int radius = width >= 8 ? 4 : width >> 1; + path = CGPathCreateWithRoundedRect(thumbBounds, radius, radius, NULL); CGContextBeginPath(context); CGContextAddPath(context, path); if (msPtr->info.trackInfo.scrollbar.pressState != 0) { |