Replace the per-cell image marker with sparse placement spans attached to
grid lines. A placement owns all of its spans and records the input
protocol, application image and placement IDs, z-index, and creation order.
This retains overlapping image layers without storing a list in every grid
cell. Grid operations move, split, clip, and remove only the affected spans.
Use the input protocol to determine image/text interaction: later text
damages SIXEL spans, while Kitty placements remain and are ordered by their
z-index. Rendering then adapts that one logical scene for each client,
rather than changing its semantics according to whether the outer terminal
uses Kitty or SIXEL.
mage reference. Deferred pane redraws explain the intermittent “image never appears” behavior.
Fixed:
- Preserves image metadata while updating the text underlay in the collected ASCII path: grid.c:779
- Handles the single-cell/non-ASCII path and schedules an image redraw: screen-write.c:2631
- Uses the requested if/else for new_id.
- Adds a deterministic regression reproducing point (2): regress/image-support.sh:240
This matches Kitty’s requirement that normal text operations must not affect graphics; graphics require
explicit deletion. Kitty graphics protocol
Build an adaptive 256-colour palette with median cut instead of using a fixed colour cube. Apply Floyd-Steinberg error diffusion while mapping pixels to reduce banding and preserve image detail.
Retain the padded canonical pixel canvas separately from the image content. Scale only the populated portion of partial edge cells so an image keeps its exact raster size on the originating terminal while retaining its cell footprint.
A resize may temporarily leave the terminal cell pixel dimensions unknown while tmux queries the terminal. Schedule another client redraw when the pixel geometry response arrives so the graphical backend replaces the temporary text fallback.
Enable the sixel feature when WezTerm is detected and clarify that the kitty terminal feature requires Unicode placeholder support rather than only the basic graphics protocol.
