To avoid passing a queue type for each kind of input (pointer, key),
introduce package input for mapping a handler key to all input events.
Future input sources can be added without changes to programs, and
as an added bonus, event ordering is preserved across input sources.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
Layouts and path builders are transient and need an ops list for
operation. However, instead of passing the ops list to every method,
pass the list in an init method and store it for subsequent methods.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
Split out OpArea from OpHandler to allow stacked areas in a followup.
Replace hit closures with static shapes (rectangles and ellipses) to
avoid allocations. If needed, generic hit functions can be introduced
again later.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
Instead of allocating and constructing a clip path, store path data
directly in op lists. Use separate op lists for cached text layout
paths.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
We're about to allow OpBlock for invoking ops from multiple (cached)
Ops containers. To allow for drawing state changes to stick after
invoking such a cached block, we can't let OpBlock perform an implicit
save and restore of drawing state.
Instead, introduce OpPush and OpPop for explicit drawing state stack
management.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
The layout package switched from interfaces to functions for
composing layouts. The switch made sure that no garbage is
generated for transient layouts such as Align, Inset, Stack, Flex.
Unfortunately, that left the stateful widgets and layouts: as soon
as their layout methods are embedded in a transient layout, a
closure is generated that escapes to the heap.
To avoid garbage for both transient as well as stateful widgets,
replace the functional approach with explicit begin/end methods.
A begin method generally starts an op block and returns the adjusted
constraints. An end method takes computed dimensions, ends its op
block and returns adjusted dimensions.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
With layout.Widget a function instead of an interface, the amount
of per-frame garbage can be drastically reduced.
The layout code ends up slightly more explicit.
As a side benefit, the awkward ordering indexing for Flex and Stack
fit nicely into their new explicit Layout methods.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
Pros:
- Much less per-frame garbage
- Allow future preprocessing of ops while building it
- Much fewer interface calls and pointer chasing
- Allow future serialization of ops for remote rendering
Cons:
- Slightly clumsier API
Signed-off-by: Elias Naur <mail@eliasnaur.com>
With an interface instead of anonymous functions, amending an
area's parameters can be done even after adding it to an OpHandler.
This will be useful when we switch to serialized op lists.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
gioui.org/ui was renamed from gioui.org/ui/ui before the release,
but the import order wasn't changed accordingly.
Signed-off-by: Elias Naur <mail@eliasnaur.com>