* fixed bug in autoscrolling that caused the content to jump between the

view's top and bottom if you moved the pointer above the view and reached
  the top
* increased auto-scrolling speed to 40 scroll steps per second and changed
  _PerformAutoScrolling() to behave as R5: do soft scrolling

git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@30463 a95241bf-73f2-0310-859d-f6bbb57e9c96
This commit is contained in:
Oliver Tappe 2009-04-27 16:14:55 +00:00
parent 077496d6d5
commit cad2c3d0a5

View File

@ -4665,20 +4665,13 @@ BTextView::_PerformAutoScrolling()
if (CountLines() > 1) {
// scroll in Y only if multiple lines!
float lineHeight = 0;
float vertDiff = 0;
// R5 does a pretty soft auto-scroll, we try to do the same by
// simply scrolling the distance between cursor and border
if (fWhere.y > bounds.bottom) {
lineHeight = LineHeight(_LineAt(bounds.LeftBottom()));
vertDiff = fWhere.y - bounds.bottom;
scrollBy.y = fWhere.y - bounds.bottom;
} else if (fWhere.y < bounds.top) {
lineHeight = LineHeight(_LineAt(bounds.LeftTop()));
vertDiff = fWhere.y - bounds.top; // negative value
scrollBy.y = fWhere.y - bounds.top; // negative value
}
// Always scroll vertically line by line or by multiples of that
// based on the distance of the cursor from the border of the view
// TODO: Refine this, I can't even remember how beos works here
scrollBy.y = lineHeight > 0 ? lineHeight * (int32)(floorf(vertDiff)
/ lineHeight) : 0;
// prevent from scrolling out of view
if (scrollBy.y != 0.0) {
@ -4686,7 +4679,7 @@ BTextView::_PerformAutoScrolling()
+ fLayoutData->bottomInset);
if (bounds.bottom + scrollBy.y > bottomMax)
scrollBy.y = bottomMax - bounds.bottom;
else if (bounds.top + scrollBy.y < 0)
if (bounds.top + scrollBy.y < 0)
scrollBy.y = -bounds.top;
}
}
@ -5285,7 +5278,8 @@ BTextView::TextTrackState::TextTrackState(BMessenger messenger)
fRunner(NULL)
{
BMessage message(_PING_);
fRunner = new (nothrow) BMessageRunner(messenger, &message, 300000);
const bigtime_t scrollSpeed = 25 * 1000; // 40 scroll steps per second
fRunner = new (nothrow) BMessageRunner(messenger, &message, scrollSpeed);
}