Commit Graph

15 Commits

Author SHA1 Message Date
Elias Naur ab9f42c820 widget: [API] replace Focus methods with explicit FocusCmds
Now that widgets by convention may be focused by issuing FocusCmd
directly, remove the now redundant Focus methods on Clickable, Editor,
Selectable.

Signed-off-by: Elias Naur <mail@eliasnaur.com>
2024-02-05 11:09:36 +00:00
Elias Naur 8334d2abb4 widget: [API] re-implement Editor.Focus in terms of commands
Signed-off-by: Elias Naur <mail@eliasnaur.com>
2024-02-05 10:59:51 +00:00
Elias Naur 6027517949 io/input: [API] introduce Source, the interface between a Router and widgets
This change gets rid of the event.Queue interface by replacing it with
input.Source values. Source provides the interface to Router necessary
to implement interface widgets.

Signed-off-by: Elias Naur <mail@eliasnaur.com>
2024-02-05 10:59:51 +00:00
Elias Naur 4fcd96ac4b layout,app: [API] rename FrameEvent.Queue and Context.Queue to Source
We're about to replace the interface Queue with a concrete input.Source.
This change renames the field accordingly.

Signed-off-by: Elias Naur <mail@eliasnaur.com>
2024-02-05 10:59:51 +00:00
Elias Naur d5a0d2cf60 io/input,io/router: [API] rename package io/router to io/input
The input name better matches its purpose, in particular when we
introduce input.Source.

Signed-off-by: Elias Naur <mail@eliasnaur.com>
2024-02-05 10:59:51 +00:00
Chris Waldon 43c47f0883 go.*,text,font{,/opentype},app,gpu,widget{,/material}: [API] load system fonts
This commit updates the text package to be able to load system fonts. As a consequence,
application authors may choose to provide no fonts manually, and it's
also possible that the system provides none (WASM, for instance, currently provides no
system fonts). As such, the text stack needed some minor tweaks to handle this case by
displaying blank spaces where text should be rather than crashing when no faces are
available.

Internally, we are dropping the old method of choosing faces and instead relying solely
on the new font matching logic in go-text. I chose to do this because maintaining two
different sets of logic with a hierarchical relationship proved to be really complex,
and also the go-text logic seems to produce higher-quality choices.

The breaking API change from this commit is the new way of constructing a text shaper
using text.ShaperOptions. Providing no options will result in a shaper that uses solely
system fonts. The various options can be used to disable system font loading and to
provide an already-parsed collection of fonts as per Gio's old API.

The material.NewTheme function now accepts no arguments instead of a font collection.
Users wanting to provide a collection can simply provide a new shaper configured how
they would like:

    theme := material.NewTheme()
	theme.Shaper = text.NewShaper(text.NoSystemFonts(), text.WithCollection(gofont.Regular()))

This commit touches many packages to fix up their construction of text shapers, mostly in
test code. The changes to the tests in package widget deserve special note:
Changing our font resolution logic caused the tofu characters within the
test strings to use a different font's tofu. This isn't a problem, but shifted
the layout of the shaped text a little bit. I've updated the numbers to expect
the new glyph positions.

Fixes: https://todo.sr.ht/~eliasnaur/gio/309
Fixes: https://todo.sr.ht/~eliasnaur/gio/184
Signed-off-by: Chris Waldon <christopher.waldon.dev@gmail.com>
2023-07-19 10:01:51 +02:00
Chris Waldon f77bf9a42c font/opentype: [API] support font collection loading
This commit adds back support for loading font collections, which we
lost when switching to the harfbuzz-based shaper last January. In
addition, this commit takes advantage of our new font loading library's
metadata facilities to automatically construct text.FontFaces for all
fonts within a collection. This is significantly more ergonomic for
users, and can be used to load single fonts with automatic metadata
detection as well.

I've exposed a opentype.Face.Font() method that can be used to get the
font metadata for a given face as well, though you have to type assert to
see it:

var myFace text.Face
if asOpentype, ok := myFace.(opentype.Face); ok {
    myFont := asOpentype.Font()
}

The one problem with this approach is that the font variant field always
be automatically populated. Mono font detection is supported, but
other variants like SmallCaps are more complicated and may need to be
expressed differently in the future (smallcaps is a feature that any font
file can have, not necessarily a separate font file). See this [0] upstream
issue for details.

Additionally, in order to avoid import cycles, I've moved the declarations
of font attributes to package font. You can fix your code automatically to
refer to the new definitions by running the following:

    gofmt -w -r 'text.FontFace -> font.FontFace' .
    gofmt -w -r 'text.Variant -> font.Variant' .
    gofmt -w -r 'text.Style -> font.Style' .
    gofmt -w -r 'text.Typeface -> font.Typeface' .
    gofmt -w -r 'text.Font -> font.Font' .
    gofmt -w -r 'text.Regular -> font.Regular' .
    gofmt -w -r 'text.Italic -> font.Italic' .
    gofmt -w -r 'text.Thin -> font.Thin' .
    gofmt -w -r 'text.ExtraLight -> font.ExtraLight' .
    gofmt -w -r 'text.Light -> font.Light' .
    gofmt -w -r 'text.Normal -> font.Normal' .
    gofmt -w -r 'text.Medium -> font.Medium' .
    gofmt -w -r 'text.SemiBold -> font.SemiBold' .
    gofmt -w -r 'text.Bold -> font.Bold' .
    gofmt -w -r 'text.ExtraBold -> font.ExtraBold' .
    gofmt -w -r 'text.Black -> font.Black' .
    gofmt -w -r 'text.Hairline -> font.Thin' .
    gofmt -w -r 'text.UltraLight -> font.ExtraLight' .
    gofmt -w -r 'text.DemiBold -> font.SemiBold' .
    gofmt -w -r 'text.UltraBold -> font.ExtraBold' .
    gofmt -w -r 'text.Heavy -> font.Black' .
    gofmt -w -r 'text.ExtraBlack -> font.Black+50' .
    gofmt -w -r 'text.UltraBlack -> font.ExtraBlack' .

Make sure each affected file imports gioui.org/font.

[0] https://github.com/go-text/typesetting/issues/57

Signed-off-by: Chris Waldon <christopher.waldon.dev@gmail.com>
2023-04-18 16:22:48 -06:00
Chris Waldon 6ab3ff40a6 font/opentype,text,widget{,/material}: [API] support bitmap glyph rendering
This commit supports rendering opentype glyphs containing bitmap data instead of
color data. In order to support returning the shaped bitmap glyphs from the Shaper's
Shape() method, it has gained a second return parameter, an op.CallOp. Adding
that CallOp immediately after or immediately before painting the returned path
will display the bitmap glyphs.

The consequences of supporting colored glyphs forced changes upon the widget APIs
for widgets that display text. Previously text always had a fixed paint material,
so we could rely upon the caller setting the material (e.g. adding a paint.ColorOp)
before painting the glyphs and everything would work. Now that we display image-
based glyphs, we end up changing the painting material to an image midway through
displaying text. This is an awkward consequence of how we currently manage the
painting material, and to work around it widgets now accept an op.CallOp that
is expected to set the proper paint material. Text widgets will use that op.CallOp
before painting text (or other paint operations) to ensure that they are painting
with the proper materials.

This, in turn, changed the APIs for laying out widget.Editor, widget.Label, and
widget.Selectable, and eliminated the need for them to accept a callback (the
callback was only really to set the colors). Dropping that callback function
allowed me to consolidate widget.Label to only need one exported Layout method,
and allowed me to unexport the PaintText, PaintCaret, and PaintSelection methods
from widget.Editor and widget.Selectable. Those methods are useless in the public
API now that they don't need to be invoked after applying a color operation.

Callers of the raw text shaper API will need to make the following changes:

- Where before you used:

	var ops *op.Ops // Assume we have an operation list.
	var shaper *text.Shaper // Assume we have a shaper.
	var col color.NRGBA // Assume we have a text color.
	var glyphs []text.Glyph // Assume we have already filled a slice of glyphs.

	shape := shaper.Shape(glyphs)
	paint.FillShape(ops, col, clip.Outline{Path:shape}.Op())

- Now you should do:

	shape, call := shaper.Shape(glyphs)
	paint.FillShape(ops, col, clip.Outline{Path:shape}.Op())
	call.Add(ops)

Callers of the widget.{Label,Selectable,Editor} APIs will need to make the
following changes:

- Where before you used:

	var gtx layout.Context // Assume we have an operation list.
	var shaper *text.Shaper // Assume we have a shaper.
	var textCol color.NRGBA // Assume we have a text color.
	var selectCol color.NRGBA // Assume we have a selection color.
	var ed widget.Editor // Assume we have an editor.
	var sel widget.Selectable // Assume we have a selectable.

	// Lay out an editor.
	ed.Layout(gtx, shaper, text.Font{}, unit.Sp(30), func(layout.Context) layout.Dimensions {
		// Paint the editor.
	})
	// Lay out a selectable.
	sel.Layout(gtx, shaper, text.Font{}, unit.Sp(30), func(layout.Context) layout.Dimensions {
		// Paint the selectable.
	})
	// Lay out an interactive label.
	widget.Label{}.LayoutSelectable(gtx, shaper, text.Font{}, unit.Sp(30), "hello", func(layout.Context) layout.Dimensions {
		// Paint the label.
	})
	// Lay out a non-interactive label.
	widget.Label{}.Layout(gtx, shaper, text.Font{}, unit.Sp(30), "hello")

- Now you should do:

	// Capture setting the text paint material in a macro.
	textColMacro := op.Record(gtx.Ops)
	paint.ColorOp{Color: textCol}.Add(gtx.Ops)
	textMaterial := textColMacro.Stop()
	// Capture setting the selection paint material in a macro.
	selectColMacro := op.Record(gtx.Ops)
	paint.ColorOp{Color: selectCol}.Add(gtx.Ops)
	selectMaterial := selectColMacro.Stop()

	// Lay out an editor.
	ed.Layout(gtx, shaper, text.Font{}, unit.Sp(30), textMaterial, selectMaterial)
	// Lay out a selectable.
	sel.Layout(gtx, shaper, text.Font{}, unit.Sp(30), textMaterial, selectMaterial)
	// Lay out a label (no difference between interactive and non-interactive)
	widget.Label{}.Layout(gtx, shaper, text.Font{}, unit.Sp(30), "hello", textMaterial, selectMaterial)

Callers of the material package API do not need to make any changes.

Signed-off-by: Chris Waldon <christopher.waldon.dev@gmail.com>
2023-03-28 09:25:15 -06:00
Chris Waldon b7d126e24c font/{gofont,opentype},text,widget{,/material}: [API] add font fallback and bidi support
This commit restructures the entire text shaping stack to enable lines of shaped text to
have non-homogeneous properties like which font face they belong to and which direction
a segment of text is going.

The text package now provides a concrete type text.Shaper which can be used to convert
strings into sequences of renderable text.Glyphs. At a high level, the API is used
like this:

    // Prepare some fonts.
    var collection []text.FontFace
    // Make a shaper with those fonts loaded.
    shaper := text.NewShaper(collection)
    // Shape a string.
    shaper.LayoutString(text.Parameters{
		PxPerEm: fixed.I(12),
    }, 0, 100, system.Locale{}, "Hello")
    // Iterate the glyphs from that string.
    for glyph, ok := shaper.NextGlyph(); ok; glyph, ok = shaper.NextGlyph() {
    	// Convert the glyph data into a path. In real uses, convert batches of glyphs
    	// rather than single glyphs to reduce the number of individual paths and offsets
    	// required to display your text.
    	shape := shaper.Shape([]text.Glyph{glyph})
    	// Offset the glyph to the position it declares within its fields. This will
    	// automatically handle correct bidirectional text glyph positioning.
    	offset := op.Offset(image.Pt(glyph.X.Floor(), int(glyph.Y))).Push(gtx.Ops)
    	// Create a clip area from the shape of the glyph.
    	area := clip.Outline{Path: shape}.Push(gtx.Ops)
    	// Paint whatever the current color is within the glyph's shape.
    	paint.PaintOp{}.Add(gtx.Ops)
    	area.Pop()
        offset.Pop()
    }

This API will transparently handle both font fallback (choosing appropriate fonts
from those loaded when the primary font doesn't contain a required glyph) and
bidirectional text (mixed left-to-right and right-to-left text). Glyphs are
iterated in order of the input runes, not their visual order, but proper use
of the provided offsets will ensure that text always displays correctly.

Thanks to Elias Naur for suggesting this glyph iterator strategy. It let us cut
through a lot of accumulated complexity from trying to match our old text APIs,
meaning that this change actually is a net negative change in lines of code.

This commit consumes the upstream github.com/go-text/typesetting/shaping API
now that my prior work is merged there, removing the need for the font/opentype/internal
package entirely.

As part of my efforts, I fuzzed both the low-level text shaping stack and the
editor widget extensively. I've committed regression tests found that way into
the appropriate testdata files to ensure the fuzzer re-checks them.

Fixes: https://todo.sr.ht/~eliasnaur/gio/425
Fixes: https://todo.sr.ht/~eliasnaur/gio/211
Signed-off-by: Chris Waldon <christopher.waldon.dev@gmail.com>
2022-12-13 22:06:57 -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 0273203743 app,io/router: expand IME snippets if a new range overlaps the old
Instead of cmpletely replacing the IME snippet for every update, expand
the old range if there is overlap. This change avoids never-ending
restarts of the IME on Android where snippets are expanded in two
calls, one for expanding before the selection and one for exanding after
the selection.

Signed-off-by: Elias Naur <mail@eliasnaur.com>
2022-04-23 13:20:46 +02:00
Elias Naur 31f55232bf app,widget,io: implement IME positioning
This change implements reporting of the caret position from Editor, as well
as Windows, macOS, Android support. As a result, the IME composition window
on Windows and macOS is now positioned correctly.

References: https://todo.sr.ht/~eliasnaur/gio/246
Signed-off-by: Elias Naur <mail@eliasnaur.com>
2022-02-13 20:09:06 +01:00
Elias Naur 216f2c3295 app: always preserve IME snippet replacement text
When a text range in the IME snippet is replaced, the replacement
is discarded if the range don't overlap with the snippet range. However,
the replacement is more relevant than whatever snippet is current.
This change discards the snippet in case of no overlap.

As a bonus, IMEs that leaves the snippet range at [0:0] will have the
snippet track the composing region now.

The FuzzIME test is adjusted to always generate replacements that overlap
Editor content; otherwise the IME snippet and editor state can't be expected
to match.

Signed-off-by: Elias Naur <mail@eliasnaur.com>
2022-02-12 12:01:10 +01:00
Elias Naur 98b02176db app: [Android] move UTF-16 to UTF-32 conversion routines to Go
They're easier to test and can be re-used for macOS/Windows.

While here, add a Go 1.18 build tag to app/ime_test.go; it relies
on Go 1.18 fuzzing.

Signed-off-by: Elias Naur <mail@eliasnaur.com>
2022-02-09 20:45:12 +01:00
Elias Naur 58cdb3e1da app,widget: implement Editor IME support, add Android implementation
Fixes: https://todo.sr.ht/~eliasnaur/gio/116
References: https://todo.sr.ht/~eliasnaur/gio/246
Signed-off-by: Elias Naur <mail@eliasnaur.com>
2022-02-06 10:31:53 +01:00