This commit ensures that text.Alignment is intuitive for
the direction of the text being aligned. RTL text with
Alignment Start will be aligned to the right edge of the area,
whereas LTR text with Alignment Start will continue to be
aligned to the left edge. Vice versa for the End alignment.
References: https://todo.sr.ht/~eliasnaur/gio/146
Signed-off-by: Chris Waldon <christopher.waldon.dev@gmail.com>
This commit updates material.Editor and material.Label to support the
new text shaper. This requires breaking their assumption that glyphs
of font data map 1:1 to runes of text data.
References: https://todo.sr.ht/~eliasnaur/gio/146
Signed-off-by: Chris Waldon <christopher.waldon.dev@gmail.com>
This commit introduces a new text shaping infrastructure
powered by Benoit Kugler's Go source-port of harfbuzz.
This shaper can properly display complex scripts and RTL
text. This commit changes the signature of the text.Shaper
function, which is a breaking API change.
The new functionality is available via opentype.ParseHarfbuzz,
which configures a text.Shaper leveraging the new backend.
References: https://todo.sr.ht/~eliasnaur/gio/146
Signed-off-by: Chris Waldon <christopher.waldon.dev@gmail.com>
With this change, the Shape function returns a clip.PathSpec
instead of a clip.Outline op. It is then possible to create
a clip.Outline or clip.Stroke op to fill the text path or
draw its stroke.
Signed-off-by: Christophe Meessen <meessen@cppm.in2p3.fr>
Some semantic information is automatically extracted, but some must be
provided by UI components. This change enriches the generic and material
widgets with such information.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
The op.Save and Load methods exist to support the need for
transformation, clip, pointer area state to behave as stacks. For
example, layout needs to apply an offset to its children but not
subsequent operations.
Before this change, op.Save and Load were used to save and restore the
state:
ops := new(op.Ops)
// Save state.
state := op.Save(ops)
// Apply offset.
op.Offset(...).Add(ops)
// Draw with offset applied.
draw(ops)
// Restore state.
state.Load()
A drawback with the op.Save mechanism is that there is no direct
connection between the state change and the saving and loading of state.
This causes confusion as to when a Save/Load is needed and who is
responsible for performing them, which leads to subtle bugs and over-use
of Save/Loads.
This change gets rid of the general state stack and replaces it with
per-state stacks. There is now a stack for transformation, clip, pointer
areas, and they can only be restored by the code pushing state to them.
The example above now becomes:
ops := new(op.Ops)
// Push offset to the transformation stack.
stack := op.Offset(...).Push(ops)
// Draw with offset applied.
draw(ops)
// Restore state.
stack.Pop()
For convenience, transformation also be Add'ed if the stack operation is
not required.
Simple state such as the current material no longer has a way to be
restored; it is assumed the client of a PaintOp adds their desired
material operation before it.
API change: replace op.Save/Load with explicit Push/Pop scopes for
op.TransformOps, pointer.AreaOps, clip.Ops.
To ease porting, this change retains a version of op.Save/Load that
saves and restores the transformation and clip stacks. It also retains
an Add method for clip.Op.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
In the new compute renderer, clipping to a complex shape is slower than
filling it. Swap the clip shapes for drawing text so that the text shape
itself is last, and therefore used for filling.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
- Allow dragging to be on both horizontal and vertical axes at once.
- Split Editor.caret.pos into caret.start and caret.stop. caret.start is
the old caret.pos, and is both the position of the caret, and also the
start of selected text. caret.end is the end of the selected text.
Start can be after end, e.g. after after Shift-DownArrow.
- Update caret.end after a mouse drag, and various shifted keys
(Shift-UpArrow, Shift-DownArrow, etc).
- Change Shortcut-C to copy only the selected text, not the whole editor
text.
- Add Shortcut-X to copy and delete selected text, and Shortcut-A to
select all text.
- The various Insert/Delete/etc functions now overwrite or delete the
selection, as appropriate.
- Change MoveCaret to accept a distance for selection end, as well.
Change SetCaret to accept a selection end offset.
- Add SelectionLen to get the selection length, Selection to get
selection offsets, SelectedText to get the selected text, and
ClearSelection to clear the selection.
- Add a rudimentary selection unit test, and extend the deleteWord unit
test with some text selection cases.
- Add SelectionColor to material.EditorStyle, which defaults to
Theme.Palette.ContrastBg.
Signed-off-by: Larry Clapp <larry@theclapp.org>
- Move caret from editBuffer.caret to Editor.caret.pos.ofs and related
refactoring. Move other fields in Editor.caret into Editor.caret.pos.
- Refactor several functions to change a position passed into them,
rather than changing e.rr.caret directly.
- Add editBuffer.Seek().
- Remove editBuffer.dump().
- Change Editor.Move to MoveCaret.
- Add Editor.SetCaret.
- Updated tests.
Signed-off-by: Larry Clapp <larry@theclapp.org>
The semantics were relaxed in a previous commit; this change renames
to operations accordingly.
API change. Use gofmt to adjust your code accordingly:
gofmt -r 'op.Push(a).Pop() -> op.Save(a).Load()'
gofmt -r 'op.Push(a) -> op.Save(a)'
gofmt -r 'v.Pop() -> v.Load()'
gofmt -r 'op.StackOp -> op.StateOp'
Signed-off-by: Elias Naur <mail@eliasnaur.com>
Commit gioui.org/commit/94d242d18c9245 broke Editor and Label clipping,
most visible for single-line Editors. Restore the correct clipping.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
Commit https://gioui.org/commit/b331407e81456 added text layout and shaping
based on io.Reader and changed Editor to use it. Unfortunately, as ~inkeliz
discovered, caching of shapes were also lost.
~inkeliz suggested fix,
https://lists.sr.ht/~eliasnaur/gio-patches/patches/15059
adds caching of shapes to Editor to regain lost performance.
This change repairs the cache to work on io.Reader API, in hope that the
already complicated Editor won't need additional caching.
Before this change, text layouts were represented as a slice of (rune, advance)
pairs. Unfortunately, this representation doesn't lend itself to caching of
shaping results, so change the representation of a line of text to be a pair
of text and advances:
package text
type Layout {
Text string
Advances []fixed.Int26_6
}
The Text field can then be used in a cache key, assuming Advances is
consistent with it.
The end result is that the two shaper variants of text.Shaper is reduced to
just one, and the Len field field of text.Line is no longer needed.
The changed representation adds a bit of extra work to package opentype.
Cleaning that up is left as a future TODO.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
PaintOp.Rect is the wrong abstraction; it implies a clip operation
better handled by package clip, and not all paints need it (colors).
Furthermore, it's awkward to specify a PaintOp that fills up the
current clip area, regardless of its size.
Redefine PathOp to mean "fill current clip area".
API change. Replace uses of PaintOp.Rect with a TransformOp applied
before the PaintOp.
Leave a TODO for the PathOp infinity area.
Fixes gio#167
Signed-off-by: Elias Naur <mail@eliasnaur.com>
Use op.Offset instead, or create and manipulate a f32.Affine2D.
API change. Update your code with a gofmt rule:
gofmt -r 'op.TransformOp{}.Offset -> op.Offset'
Signed-off-by: Elias Naur <mail@eliasnaur.com>
The funcs replace stack.Push and macro.Record, which become private.
This makes stack and macro faster to write, in particular for stacks
where you can just write the following line to save and restore the
state :
defer op.Push(ops).Pop()
This usage requires Push to return a pointer (since Pop has a pointer
receiver), or else the code doesn't compile.
For consistancy, I tried to do the same for op.Record, but this implied
to turn all the MacroOp fields into pointers, and this caused some
panics. As a result, op.Record doesn't return a pointer.
An other side effect pointed by Larry Clapp: StackOp and MacroOp are not
re-usable any more, you have to allocate a new one for each usage, using
the described funcs above.
Signed-off-by: Thomas Bruyelle <thomas.bruyelle@gmail.com>
Change the definition of Widget from the implicit
type Widget func()
to the explicit functional
type Widget func(gtx layout.Context) layout.Dimensions
The advantages are numerous:
- Clearer connection between the incoming context and the output dimensions.
- Returning the Dimensions are impossible to omit.
- Contexts passed by value, so its fields can be exported
and freely mutated by the program.
The only disadvantage is the longer function literals and the many "returns".
What tipped the scales in favour of the explicit Widget variant is that type
aliases can dramatically shorten the literals:
type (
C = layout.Context
D = layout.Dimensions
)
widget := func(gtx C) D {
...
}
Note that the aliases are not part of the Gio API and it is up to each user
whether they want to use them.
Finally the Go proposal for lightweight function literals,
https://github.com/golang/go/issues/21498, may remove the disadvantage
completely in future.
Context becomes a plain struct with only public fields, and its Reset is
replaced by a NewContext convenience constructor.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
Instead of
type Contraints struct {
Width, Height Constraint
}
use
type Constraints struct {
Min, Max image.Point
}
which leads to simpler use. For example, the Min method is trivally replaced by
the field, and the RigidConstraints constructor is no longer a net win.
API Change. Rewrites:
gofmt -r 'gtx.Constraints.Min() -> gtx.Constraints.Min'
gofmt -r 'gtx.Constraints.Width.Min -> gtx.Constraints.Min.X'
gofmt -r 'gtx.Constraints.Height.Min -> gtx.Constraints.Min.Y'
gofmt -r 'gtx.Constraints.Height.Max -> gtx.Constraints.Max.Y'
gofmt -r 'gtx.Constraints.Width.Max -> gtx.Constraints.Max.X'
Signed-off-by: Elias Naur <mail@eliasnaur.com>
First, replace LayoutOptions with an explicit maximum width parameter. The
single-field option struct doesn't carry its weight, and I don't think we'll
see more global layout options in the future. Rather, I expect options to cover
spans of text or be part of a Font.
Second, replace the unit.Converter with an scaled text size. It's simpler and
allow the Editor and similar widgets to easily detect whether their cached
layouts are stale. Package text no longer depends on package unit, which is
now dealt with at the widget-level only.
Finally, remove the Size field from Font. It was a design mistake: a Font is
assumed to cover all sizes, as evidenced by the FontRegistry disregarding
Size when looking up fonts.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
In preparation for using Shaper with an io.Reader, rework the API to not refer
to strings. In particular, introduce Glyph for holding the rune in addition to
the advance. For fast traversing of the underlying text, add Len to Line with
the UTF8 length.
Layout is a useless wrapper around []Line; remove it while we're
here.
Signed-off-by: Elias Naur <mail@eliasnaur.com>
Chris Waldon