1# Terminal images
2
3[Back to the README](../README.md)
4
5vev-vt supports a subset of the Kitty graphics protocol for static images sent
6directly through terminal output, including the form used by:
7
8```sh
9kitten icat --transfer-mode=stream image.png
10```
11
12Your application reads the result through `Screen.GraphicsSnapshot()` and chooses
13how to display it. This library does not open a window.
14
15## Supported
16
17- PNG, RGB and RGBA images, with explicit resource limits.
18- Direct image transmission, display, placement, queries and supported deletion.
19- Chunked Base64 data, with optional zlib compression.
20- Cropping, cell-based placement, pixel offsets and z-index.
21- Placements with only `c=` or only `r=` keep the displayed region's aspect
22  ratio: the other value is the rounded-up size derived from the cell pixel
23  size (1:2 width:height when the screen pixel size is unknown), at least 1.
24  `c=0` and `r=0` mean unset.
25- Movement and clipping as terminal rows scroll.
26
27Images are stored separately from text history. The `graphics` package contains
28the image model; `protocol/kittygraphics` reads Kitty commands and updates it.
29Graphics state is allocated only when a screen receives a graphics command.
30
31## Not supported
32
33File or shared-memory transfers, animation, image composition, relative
34placements and Unicode placeholders are not implemented. Image placements do
35not support resize reflow.
36
37## Inspect a capture without a display
38
39The development harness reads captured terminal bytes and writes a PNG:
40
41```sh
42go run ./cmd/graphics-harness \
43  -input internal/graphicsharness/testdata/demo.apc \
44  -output /tmp/graphics-harness.png \
45  -cols 4 -rows 4 -pixel-width 4 -pixel-height 4 -scale 64
46```
47
48The included example produces a blue background with a translucent red overlay.
49This harness is an inspection tool, not an interactive terminal emulator.