In unhook, add the generated image to a list of finished sixel images,
along with positioning and size information.
When rendering, loop this list of images, and render the images (or
parts of) that are visible.
When scrolling, check if any part of the images cover the re-cycled
lines, and if so, remove the *entire* image from the list.
This means we have the following limitations:
* The renderer always renders the whole (visible area of) the
image(s). There are times when this isn't necessary - for example,
when the image is scrolled inside the visible area.
* It would be nice if we could crop the image when parts of it is
scrolled out.
When we scroll up, we need to ensure that we don't scroll too far,
"past" the scrollback limit. I.e. we need to ensure we don't wrap
around.
The code did this. But, in certain scenarios, the resulting view
points into uninitialized scrollback history.
This happens when we haven't yet filled the entire scrollback, and
scroll up enough lines to wrap around the scrollback. The old code
would adjust the view for the wrap around, but doing so pointed the
view at the not-yet utilized scrollback.
This implements basic parsing of sixel data. Lots of limitations and
temporary solutions as this is still work-in-progress:
* Maximum image size hardcoded to 800x800
* No HLS color format support
* Image is always rendered at 0x0 in the terminal
Tab is one of the keys included in our "otherModifierKeys"
implementation. However, since the key sym falls outside the checks
required to trigger it, special case it and implement its sequences as
a table.
Backspace now emits DEL for all non-ctrl modifier combos, and BS for
all ctrl modifier combos.
The alt modifier prefixes DEL/BS with ESC.
This also removes my own hack of mapping ctrl+backspace to
alt+backspace.
Describe backspace behavior in both the README and the man page.
TODO: implement DECBKM to allow applications to toggle the backspace
behavior.
