This is needed for example when a selection has both `line1` and `col1`
at 1, and the left arrow is pressed: `line2` and `col2` change, while
`line1` and `col1` don't, but we still want to scroll.
Fixing the Node's clipping rectangle make the clipping in DocView:draw()
partially redundant. This latter is now no longer needed to clip
on the right when drawing the document's lines but it still serves to
the purpose of clipping on the left, before the gutter region.
This function gets called at every `core.step`, so we should avoid
having to recalculate the scrollable size every time, as it could get
very expensive on long lines.
Useful to draw whitespaces with alternate characters and colors
without slowing down the text rendering.
A new API is implemented. A renderer.replacements object can be created
to list the replacements.
In turns the function renderer.draw_text and draw_text_subpixel now accept
two optional arguments for replacements.
In order to fix the issue with cursor positioning a subpixel-aware draw
text operation within rencache was required.
With this modification the cursor positioning problem is completely
resolved.
A new function renderer.draw_text_subpixel is introduced to perform
consecutive, inline, text drawings with subpixel accuracy.
In order to get right the cursor position on text on mouse clicks it is
needed to take into account text's subpixel positioning.
This fix mostly corrects the problem but cursor positioning is still
somewhat inaccurate for long lines due to repeated commands to draw a text
along a line. Repeated draw text calls make the subpixel information
lost and small errors will add-up.
With the new behavior when moving right and triggering a scroll in the
right direction a subsequent movement left do not longer triggers a
scrolling to the left.
The scrolling to the left happens only when needed for the visibility of
the current position.
In other terms with the old behavior the scrolling was purely a function
of the position and was adjusted even when not strictly needed for the
visibility of the cursor.
Now the scrolling is no longer a pure function of the position but it
has a "memory" behavior. The scrolling will be adjusted only if needed
to accommodate the position of the cursor.
Reduce also the width of the margin when the scrolling will be
triggered and calculate as a function of the font character width.
With the modification now Lite behaves like the other editors. In
addition the selection of text with the mouse is much more easy when
a scrolling of the line is needed.
Guldoman
Jipok
Adam
Joshua Minor
Francesco Abbate
cukmekerb
liquidev
daubaris