Panels can be anchored to a widget in another hierarchy, allowing for
things like cascading menus. They can also be extended via referencing
them by name, allowing for subsystems to add items to an already panel
(eg, extending a menu).
This prevent the layout system from repositioning the text view and thus
breaking text-shaping. Now Tengwar Telcontar looks much more balanced in
the widgets.
Skipping the root view (widget) sort of made sense before windows became
separate canvases as there was only the one hierarchy, but doing so
prevented windows (panels) from fitting themselves to their children.
However, now I need to think of a good way of specifying a minimum size
for panels.
WIdgets can't possibly be active when the entire UI is hidden, and
resetting the active widget when hiding the UI helps when the state gets
broken due to widget id conflicts.
The intent is to use them for menus, tooltips and anything else along
those lines, but windows was a good starting point (and puts a border
along the top of the window too).
It's not perfect as the first N expanding children get grown by 1 pixel
regarless of weight, but it's much better than leaving a (possibly quite
large) gap at the edge of the layout.
I'm not sure this is what I want, especially in the long run, but it
does make simple windows much easier to create (and not look broken due
to being specified too small).
Canvas draw order is sorted by group then order within the group. As a
fallback, the canvas entity id is used to keep the sort stable, but
that's only as stable as the ids themselves (if the canvases are
destroyed and recreated, the ids may switch around).
Shaped text is cached using all the shaping parameters as well as the
text itself as a key. This makes text shaping a non-issue for imui when
the text is stable, taking my simple test from 120fps to 1000fps
(optimized build).
As I had long suspected, building large hierarchies is fiendishly
expensive (at least O(N^2)). However, this is because the hierarchies
are structured such that adding high-level nodes results in a lot of
copying due to the flattened (breadth-first) layout (which does make for
excellent breadth-first performance when working with a hierarchy).
Using tree mode allows adding new nodes to be O(1) (I guess O(N) for the
size of the sub-tree being added, but that's not supported yet) and
costs only an additional 8 bytes per node. Switching from flat mode to
tree mode is very cheap as only the additional tree-related indices need
to be fixed up (they're almost entirely ignored in flat mode). Switching
from tree to flat mode is a little more expensive as the entire tree
needs to be copied, but it seems to be an O(N) (size of the tree).
With this, building the style editor window went from about 25% to about
5% (and most of that is realloc!), with a 1.3% cost for switching from
tree mode to flat mode.
There's still a lot of work to do (supporting removal and tree inserts).
By default, horizontal and vertical layouts expand to fill their parent
in their on-axis direction (horizontally for horizontal layouts), but
fit to their child views in their off-axis.
Flexible space views take advantage of auto-expansion, pushing sibling
views such that the grandparent view is filled on the parent view's
on-axis, and the parent view is filled by the space in the parent view's
off-axis. Flexible views currently have a background fill, allowing them
to provide background filling of the overall view with minimal overdraw
(ancestor views don't need to have any fill at all).
I had forgotten that Hash_NewTable checked the hashctx parameter, so
calling Hash_NewTable in the struct initializer meant the hasctx was
uninitialized.
This takes care of element order stability. It did need reworking the
mouse tracking code (including adding an active flag to views), but now
buttons seem to work correctly.
It's there for a reason :P. Fixes most of the really bad behavior after
disabling some widgets (re-layout isn't working at all, though, and
adding the widgets back again puts them in the wrong place).
Using label + key_offset in both imui_state_getkey and the call to
Hash_Find greatly simplifies the logic of using the correct key. Fixes
an ever-growing set of buttons when using separators (hmm, I think this
means pruning isn't working correctly).
TextContent seems redundant at this stage since a text view is always
sized to its content, and PercentOfParent doesn't work yet. Pixels
definitely works and Null seems to work in that it does no sizing or
positioning. Vertical layout is supported but not yet tested, similar
for ChildrenSum, but I can have two buttons side by side.
Text_StringView sets the view bounds to the bounds of the glyphs in the
view. This has its advantages, but is not suitable for automatic UI
sizing. However, the view is positioned correctly, so nothing needs to
be done there. Now full height glyphs (eg, C) look balanced in the view,
and glyphs with descenders (g) brush the bottom of the view.
Both passage and simple text are supported, but only simple text has
been tested at this stage. However, as passage text was taken directly
from rua_gui.c and formed the basis for simple text rendering, I expect
it's at least close to working.
The same underlying mechanism is used for both simple text strings and
passages, but without the intervening hierarchy of paragraphs etc.
Results in only the one view for a simple text string.
