Before this change MacroOp.Record simply reserved enough space for Stop to fill
out. If a user Record but never Stop'ed a MacroOp, the resulting Ops buffer
would end up with a zero, invalid opcode and panic at decode.
Fill out an empty MacroOp at Record, ensuring the Ops remains valid.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
Before this change, there was no guarantee that a PopOp matched
the intended PushOp. With a single stack operation, the client is
forced to match pop with the right push.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
Move the Record and Stop methods from Ops to MacroOp itself.
Before this change, Ops.Stop stopped the recording of the most
recent macro, which could be a different macro than intended.
After this change, there is no such confusion.
As a bonus, the Ops API becomes less cluttered.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
Before this change, clients were expected to set up the current
material (color or image) before laying out Labels and Editors.
This was done to avoid garbage from a hypothetical material
interface covering both colors and images.
However, some widgets need more than one material: the Editor had
HintImage for the hint text material.
This change implements generalized materials through blocks:
anywhere a material is expected, a ui.BlockOp is is assumed to
contain the operation(s) needed for setting the desired material.
This way we avoid allocations (interfaces) and keep the
abstraction over material types.
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>
To prepare support for cached OpBlock to refer to other Ops lists.
The exposure of OpsReader is alleviated by the removal of the Refs
and Data accessors for Ops.
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>
Elias Naur