Commit Graph

30 Commits

Author SHA1 Message Date
Chris Waldon b67b322978 widget: define incrementing combinedPos and test
This commit restructures seekPosition from a complex state-manipulating
loop into a simple loop of iteratively applying an increment operation
to the combinedPos. The increment operation itself is now tested, and
much easier to understand.

Signed-off-by: Chris Waldon <christopher.waldon.dev@gmail.com>
2022-10-22 18:19:19 -06:00
Chris Waldon 1be58a2bc4 widget: test firstPos
This commit adds a test to lock in the correct behavior of the
firstPos helper method.

Signed-off-by: Chris Waldon <christopher.waldon.dev@gmail.com>
2022-10-22 18:19:15 -06:00
Chris Waldon b46c0f5907 widget: use reliable text direction checks, not heuristics
This commit switches the way in which the editor and helper functions check
for RTL text from a heuristic to using the actual text direction.

Signed-off-by: Chris Waldon <christopher.waldon.dev@gmail.com>
2022-10-22 18:19:08 -06:00
Elias Naur 3d37491342 all: [API] replace unit.Value with separate unit.Dp, unit.Sp types
The unit.Value is a struct and thus more inconvenient to use than its
underlying float32 type. In addition, most uses don't need a general
value, but rather a specific unit given by the context. This change
replaces unit.Value with two float32 units, Dp and Sp. It also changes
variables and parameters of unit.Value to a specific unit type matching
the context. That is, unit.Dp everywhere except for text sizes which are
in Sp.

Switching to typed float32s has multiple advantages

- They can be constants:

const touchSlop = unit.Dp(16)

- Casting untyped constants is no longer necessary:

insets := layout.UniformInset(16)

- Calculation with values is natural:

func (s ScrollbarStyle) Width() unit.Dp {
	return s.Indicator.MinorWidth + s.Track.MinorPadding + s.Track.MinorPadding
}

The main API change is that calls to gtx.Px must be replaced with either
gtx.Dp or gtx.Sp depending on the unit.

Idea by Christophe Meessen.

Signed-off-by: Elias Naur <mail@eliasnaur.com>
2022-05-31 10:24:09 +02:00
Elias Naur a63e0cb44a all: [API] change op.Offset to take integer coordinates
op.Offset is a convenience function most often used by layouts. Layouts
usually operate in integer coordinates, and the float32 version of op.Offset
needlessly force conversions from int to float32. This change makes op.Offset
take integer coordinates, to better match its intended use.

Signed-off-by: Elias Naur <mail@eliasnaur.com>
2022-05-31 10:24:09 +02:00
Chris Waldon 7daab97fab widget: [API] make text.Alignment direction-sensitive
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>
2022-03-18 08:05:06 +01:00
Chris Waldon 42c99a5cb2 widget{,/material}: [API] update editor to support complex scripts
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>
2022-03-18 08:03:46 +01:00
Chris Waldon 1e5a3696f5 deps,text,widget,font/opentype: [API] add harfbuzz-powered text shaper
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>
2022-03-18 08:01:44 +01:00
Elias Naur 41489fb732 widget: replace segmentIterator with simpler functions
The replacement functions all use the single seeking function, seekPosition.

Signed-off-by: Elias Naur <mail@eliasnaur.com>
2022-02-17 18:55:30 +01:00
Christophe Meessen a34e239c04 text,widget,opentype: change text.Face.Shape to return a clip.PathSpec
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>
2021-12-19 13:30:45 +01:00
Elias Naur 6b1ca4ca7e widget: add semantic descriptions
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>
2021-12-01 17:57:04 +01:00
Elias Naur 936c266b03 all: [API] split operation stack into per-state stacks
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>
2021-10-08 17:21:56 +02:00
Elias Naur 23a839a29d widget: clip by most complex shape last
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>
2021-04-27 16:49:06 +02:00
Larry Clapp 34273940a0 widget,widget/material: add selection to the editor
- 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>
2021-01-24 09:44:52 +01:00
Larry Clapp e78bd15564 widget: refactoring to prep for editor selection
- 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>
2021-01-24 09:44:41 +01:00
Elias Naur d331dd2de8 op: rename StackOp/Push/Pop to StateOp/Save/Load
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>
2021-01-12 21:28:59 +01:00
Elias Naur ede632b265 widget: fix Editor and Label clipping
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>
2020-12-06 22:57:11 +01:00
Elias Naur aee87baefe text: represent laid out text as strings to facilitate caching of layouts
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>
2020-11-16 16:02:30 +01:00
Elias Naur 94d242d18c op/paint: remove support for PaintOp.Rect
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>
2020-11-05 16:32:19 +01:00
Elias Naur 878131189b all: remove redundant op.TransformOp.Offset
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>
2020-06-21 22:41:56 +02:00
Thomas Bruyelle ae8a377cda op: add op.Push and op.Record funcs
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>
2020-06-02 10:39:56 +02:00
Elias Naur 3af01a3f43 layout: change Widget to take explicit Context and return explicit Dimensions
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>
2020-05-23 22:28:49 +02:00
Elias Naur 013ea395b4 all: use new rectangle and point convenience functions
Signed-off-by: Elias Naur <mail@eliasnaur.com>
2020-05-19 11:03:30 +02:00
Elias Naur 7bf3265ccd layout,widget: transpose Constraints to use image.Points for limits
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>
2020-05-19 09:58:07 +02:00
Elias Naur 4c220f4554 text: simplify text layout and shaping API
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>
2020-02-03 23:32:55 +01:00
Elias Naur b331407e81 text: add io.Reader Layout method to Shaper
use them for Editor, which is no longer required to construct a string
for laying out its content.

Signed-off-by: Elias Naur <mail@eliasnaur.com>
2020-01-13 21:38:54 +01:00
Elias Naur 16d2a3ac0a text: remove String, Layout and add Glyph
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>
2020-01-13 19:54:11 +01:00
Elias Naur e25b1639b9 text: make Shaper an interface
And rename out the caching implementation to FontRegistry.

Signed-off-by: Elias Naur <mail@eliasnaur.com>
2020-01-13 14:48:31 +01:00
Elias Naur e2d0b3cfca layout: invert baseline to measure positive distance from bottom
With an inverted baseline, the zero value results in the widget
baseline aligned to its bottom.

Signed-off-by: Elias Naur <mail@eliasnaur.com>
2019-10-16 00:49:52 +02:00
Elias Naur ff3fc7a24a widget,text: move Label and Editor from text to widget package
Signed-off-by: Elias Naur <mail@eliasnaur.com>
2019-10-12 14:04:34 +02:00