Add render state C APIs for iterating only rows that require a redraw
and for marking a completed frame clean in one call.
A one-row update in a 24-row viewport reduces dirty-row discovery from
50 calls to two, while cleanup becomes one call instead of O(N) of rows.
This lower call count is massive for environments where FFI is expensive
(Go, wasm).
The dirty next API outputs the viewport y because it jumps, unlike the
normal sequential next where its trivial for a caller to keep track.
Add render state C APIs for iterating only rows that require a redraw
and for marking a completed frame clean in one call.
A one-row update in a 24-row viewport reduces dirty-row discovery from
50 calls to two, while cleanup becomes one call instead of O(N) of rows.
This lower call count is massive for environments where FFI is expensive
(Go, wasm).
The dirty next API outputs the viewport y because it jumps, unlike the
normal sequential next where its trivial for a caller to keep track.
A normal renderer would have to call `ghostty_render_state_get`
_eight times_ to reconstruct the cursor. In languages where FFI is
expensive (Go, wasm, etc.), this showed up in profiles of every frame.
Add a sized cursor snapshot and expose it. Also expose the existing color
snapshot through ghostty_render_state_get and remove the older
dedicated color getter.
Terminal construction previously accepted GhosttyTerminalOptions with
dimensions and one scrollback byte limit. Remove the options struct from
the ABI and make ghostty_terminal_new accept columns and rows directly.
Add byte and line limit options to ghostty_terminal_set and forward them
to the runtime Terminal setters. NULL removes a limit, while zero bytes
disables scrollback. Update type metadata, tests, and all API examples.
Render state already tracks the selected cell range for each viewport row,
but C renderers could only get the full terminal selection. That required
consumers to map global selection pins back into row-local spans themselves.
Add row selection data to the render-state row API. Querying the new row
data returns GHOSTTY_NO_VALUE for unselected rows and writes the inclusive
start and end columns for selected rows. The render example now demonstrates
setting a selection and reading the row-local range while iterating rows.
The GRAPHEMES_BUF data kind previously required a double pointer
(pointer to a uint32_t*) because the OutType was [*]u32, making the
typed out parameter *[*]u32. Change OutType to u32 so that callers
pass a plain uint32_t* buffer directly, which is the natural C
calling convention. The implementation casts the out pointer to
[*]u32 internally to write into the buffer.
The STYLE data kind read directly from the render state style array
without checking whether the cell actually had non-default styling.
The style data is undefined for unstyled cells, so this caused a
panic on a corrupt enum value when the caller read the style of an
unstyled cell. Now check cell.hasStyling() first and return the
default style for unstyled cells.
Expand the c-vt-render example to exercise dirty tracking, color
retrieval, cursor state, row/cell iteration with style resolution,
and dirty state reset. Break the example into six doxygen snippet
regions and reference them from render.h.
Introduce the first public C render-state surface for libghostty-vt.
Before this change, the render-state path was only available in Zig,
so C embedders had no direct way to create and update that cache.
Add an opaque GhosttyRenderState type with new, update, and free
entry points, then wire those symbols through the C API bridge and
library exports. Keep the surface intentionally minimal for now so
ownership and update behavior are established before adding read
accessors.
