The renderer bound every texture through one
`binding_array<texture_2d<f32>>` indexed per primitive. That needs
`VK_EXT_descriptor_indexing`, which a real share of Android GPUs do not
have, so the shape did not run there at all.
Split the two things being bound, since they want opposite treatment:
- Glyph atlas pages become layers of one `texture_2d_array`. A glyph
primitive carries a layer rather than a view/sampler index pair, and a
layer index is an ordinary sampling operand -- no extension. Growing the
atlas recreates the array with headroom and copies the old layers across
GPU-side.
- A standalone image gets its own texture and its own bind group, and
draws in its own call. It no longer needs a per-instance entry in
`PrimitiveData` at all: the bind group has already picked the texture.
`Primitives` therefore keeps images in a list of their own, with
`PrimitiveChange::is_image` saying which list a renumbering belongs to --
the two have independent index spaces, so `(layer, inst_idx)` alone would
collide between them.
Verified on this machine's real GPU (Venus onto an RX 7900 XT, confirmed
by the loaded ICD rather than assumed): the `tabs` example renders
byte-identical screenshots before and after, both for a text-and-rect tab
and for one holding a standalone image.
`update` redrew everything when `resized` was set, but `needs_redraw` --
which is what decides whether to request a frame at all -- did not know
about `resized`. A condition in one and not the other is a frame nobody
asks for and a stale window. The two share one `needs_redraw_all` now.
Latent on Wayland, because winit requests a redraw after a resize by
itself; a resize changes neither the root nor any widget, so nothing else
here would have asked. It stops being latent on Android, where the
surface work will not have winit underneath it and every rotation and
keyboard open is a resize.
This is not a fix for the startup defect recorded in RUST.md, where the
window keeps its pre-configure layout: that reproduces with this change
in place, and the frame it needs is requested and drawn.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>