Variable Fonts support - Revision history

Tavmjong: /* Internal Pango Support */

2018-03-23T20:46:55Z

Internal Pango Support

← Older revision		Revision as of 20:46, 23 March 2018
Line 63:		Line 63:

	Pango uses a different mechanism for handling ''variations'' from 'font-feature-settings'. Variations are handled in the Pango font description while features are handled by setting attributes.		Pango uses a different mechanism for handling ''variations'' from 'font-feature-settings'. Variations are handled in the Pango font description while features are handled by setting attributes.

			=== Harfbuzz Support ===

			From 1.4.2 Change Log (23 Jan 2017):

			<pre>
			- Implement OpenType Font Variation tables avar/fvar/HVAR/VVAR.
			- hb-shape and hb-view now accept --variations.
			- New API:

			hb_variation_t
			hb_variation_from_string()
			hb_variation_to_string()

			hb_font_set_variations()
			hb_font_set_var_coords_design()
			hb_font_get_var_coords_normalized()

			hb-ot-var.h:
			hb_ot_var_axis_t
			hb_ot_var_has_data()
			hb_ot_var_get_axis_count()
			hb_ot_var_get_axes()
			hb_ot_var_find_axis()
			hb_ot_var_normalize_variations()
			hb_ot_var_normalize_coords()

			- MVAR to be implemented later. Access to named instances to be
			implemented later as well.
			</pre>

	==== Compiling/Linking ====		==== Compiling/Linking ====

Tavmjong: /* Inkscape */

2018-03-19T14:11:55Z

Inkscape

← Older revision		Revision as of 14:11, 19 March 2018
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	Reading of 'font-variation-settings' implemented. <strike>Needs fixing (incorrect parsing, parsing not robust against variations in white-space)</strike>. FIXED.		Reading of 'font-variation-settings' implemented. <strike>Needs fixing (incorrect parsing, parsing not robust against variations in white-space)</strike>. FIXED.

	~~If linked to~~ Pango >= 1.41.1:		Rendering implemented. Requires Pango >= 1.41.1; FreeType >= 2.8 (2.9?). Axes values are not yet clamped to allowed range.

	* Font variations in existing files will be listed in the Font-Style drop-down menu.		GUI not implemented.
	* Text with variations will be displayed properly in the Text and Font dialog (the display uses Pango directly).
	* On canvas rendering does not ~~work. For the canvas, we use font outlines from Freetype~~. ~~The Freetype font reference returned from Pango seems to be missing the variable font info:~~

	~~pango_fc_font_lock_face()~~		=== Notes ===

			==== Gettting a FreeType Font Handle ====

	~~Note:~~ Pango ~~uses a different mechanism for handling ''~~variations~~'' from 'font-feature-settings'. Variations are handled in~~ the Pango font ~~description while features are handled by setting attributes.~~		Pango handles font variations via the Pango Font Description however the FreeType font retrieved via:

	~~Hint~~: To compile and link with libraries in /usr/local execute:		pango_fc_font_lock_face() (which calls pango_ft2_font_get_face())

			using the descriptor does not have the 'variation' axes set. We must do that ourselves. In principle this works with FreeType 2.8 but I seemed to need 2.9 to get it to work.

			==== Internal Pango Support ====

			This works:
			pango-view --font="Noto Sans @wght=900" --text=Test

			Pango passes the font variation info onto HarfBuzz via hb_font_set_variations() in pangofc-shape.c for shaping. But this is used only to get glyph positions.

			Pango uses a different mechanism for handling ''variations'' from 'font-feature-settings'. Variations are handled in the Pango font description while features are handled by setting attributes.

			==== Compiling/Linking ====

			To compile and link with libraries in /usr/local execute:

	export PKG_CONFIG_PATH=/usr/local/lib/pkgconfig		export PKG_CONFIG_PATH=/usr/local/lib/pkgconfig

	before running ''cmake''.		before running ''cmake'' in the Inkscape build directory.

			Building and using freetype is a bit more complicated:

			* To build:
			*# mkdir build
			*# cd build
			*# cmake -D BUILD_SHARED_LIBS:BOOL=true ..
			*# make
			*# sudo make install
			* To use:
			*# export LD_LIBRARY_PATH=/usr/local/lib

	== User Interface ==		== User Interface ==

	On the UI, I've been thinking of sliders as the dumb-obvious solution to select values for a variable font axes, but I also think it would be cool to think of a user-defined "palette" of varfont instances. Because you have pretty much infinite variations that can be chosen in a varfont, but you'd want to pick some and use them on your document and then be able to tweak one of the instances and then see the change affecting all places where that was used. So, a varfont can have typedesigner-specified named instances, but I think we should also offer user-defined instances. And these should show up on the font selector just like nowadays we have a drop-down for Regular/Bold/Italics. [[User:Juca\|Felipe "Juca" Sanches]] ([[User talk:Juca\|talk]])		On the UI, I've been thinking of sliders as the dumb-obvious solution to select values for a variable font axes, but I also think it would be cool to think of a user-defined "palette" of varfont instances. Because you have pretty much infinite variations that can be chosen in a varfont, but you'd want to pick some and use them on your document and then be able to tweak one of the instances and then see the change affecting all places where that was used. So, a varfont can have typedesigner-specified named instances, but I think we should also offer user-defined instances. And these should show up on the font selector just like nowadays we have a drop-down for Regular/Bold/Italics. [[User:Juca\|Felipe "Juca" Sanches]] ([[User talk:Juca\|talk]])

Tavmjong: /* Inkscape */

2018-03-15T10:48:42Z

Inkscape

← Older revision		Revision as of 10:48, 15 March 2018
Line 39:		Line 39:
	Linked to recent libraries, Inkscape can use "named" variations out-of-the box (i.e., one font file provides multiple styles).		Linked to recent libraries, Inkscape can use "named" variations out-of-the box (i.e., one font file provides multiple styles).

	Reading of 'font-variation-settings' implemented. Needs fixing (incorrect parsing, parsing not robust against variations in white-space).		Reading of 'font-variation-settings' implemented. <strike>Needs fixing (incorrect parsing, parsing not robust against variations in white-space)</strike>. FIXED.

	Pango uses a different mechanism for handling ''variations'' from 'font-feature-settings'. Variations are handled in the Pango font description while features are handled by setting attributes.		If linked to Pango >= 1.41.1:

			* Font variations in existing files will be listed in the Font-Style drop-down menu.
			* Text with variations will be displayed properly in the Text and Font dialog (the display uses Pango directly).
			* On canvas rendering does not work. For the canvas, we use font outlines from Freetype. The Freetype font reference returned from Pango seems to be missing the variable font info:

			pango_fc_font_lock_face()


			Note: Pango uses a different mechanism for handling ''variations'' from 'font-feature-settings'. Variations are handled in the Pango font description while features are handled by setting attributes.

	Hint: To compile and link with libraries in /usr/local execute:		Hint: To compile and link with libraries in /usr/local execute:

Tavmjong: /* Overview */

2018-03-15T10:37:04Z

Overview

← Older revision		Revision as of 10:37, 15 March 2018
Line 4:		Line 4:
	Fonts with '''Variations''' allow one to change the font appearance (weight, spacing, etc.) over a continuous range of values, all with just one font file. For an more information see this [https://webdesign.tutsplus.com/articles/how-to-use-variable-fonts-on-the-web--cms-30212 tutorial].		Fonts with '''Variations''' allow one to change the font appearance (weight, spacing, etc.) over a continuous range of values, all with just one font file. For an more information see this [https://webdesign.tutsplus.com/articles/how-to-use-variable-fonts-on-the-web--cms-30212 tutorial].

	Our font rendering stack now includes support for font variations (harfbuzz (1.4), pango (1.41.1), freetype).		Our font rendering stack now includes support for font variations (harfbuzz (1.4), pango (1.41.1), freetype (2.8/2.9).

	== References ==		== References ==

Tavmjong: /* Browser Support */

2018-03-09T13:21:31Z

Browser Support

← Older revision		Revision as of 13:21, 9 March 2018
Line 24:		Line 24:
	Firefox nightly does not support "named" variations.		Firefox nightly does not support "named" variations.

	Note: Chrome also supports 'font-weight' values that are not multiples of 100 (CSS Fonts Level 4 changes the allowed values of 'font-weight to include all integers from 1 to 1000):		Note: Chrome also supports 'font-weight' values that are not multiples of 100 (CSS Fonts Level 4 changes the allowed values of 'font-weight' to include all integers from 1 to 1000):

	[http://tavmjong.free.fr/SVG/font_weight/font_weight.svg Test file]		[http://tavmjong.free.fr/SVG/font_weight/font_weight.svg Test file]

Tavmjong: /* references */

2018-03-09T13:18:30Z

references

← Older revision		Revision as of 13:18, 9 March 2018
Line 1:		Line 1:
	== ~~references~~ ==
			== Overview ==

			Fonts with '''Variations''' allow one to change the font appearance (weight, spacing, etc.) over a continuous range of values, all with just one font file. For an more information see this [https://webdesign.tutsplus.com/articles/how-to-use-variable-fonts-on-the-web--cms-30212 tutorial].

			Our font rendering stack now includes support for font variations (harfbuzz (1.4), pango (1.41.1), freetype).

			== References ==

			=== Specifications ===

			* [https://docs.microsoft.com/en-us/typography/opentype/spec/otvaroverview OpenType Font Variations Overview]
			* [https://drafts.csswg.org/css-fonts-4/#propdef-font-variation-settings CSS Fonts Level 4 'font-variation-settings' property]

			=== Browser Support ===

			* Chrome: Supported
			* Safari: Supported (haven't tested)
			* Firefox: In Nightly but must be [https://www.axis-praxis.org/blog/2017-04-05/17/how-to-get-variable-fonts-working-in-safari-chrome-and-firefox-macos enabled].
			* Edge: ?

			[http://tavmjong.free.fr/SVG/font_weight/font_variation.svg Test file]

			Firefox nightly does not support "named" variations.

			Note: Chrome also supports 'font-weight' values that are not multiples of 100 (CSS Fonts Level 4 changes the allowed values of 'font-weight to include all integers from 1 to 1000):

			[http://tavmjong.free.fr/SVG/font_weight/font_weight.svg Test file]

	=== Google's FontView proof-of-concept ===		=== Google's FontView proof-of-concept ===

	FontView is a demo program written by Google engineers to demonstrate the variable font technologies recently added to harfbuzz and freetype.		FontView is a demo program written by Google engineers to demonstrate the variable font technologies recently added to harfbuzz and freetype.
	This is the same stuff we'll use in inkscape soon. The project sources are available at https://github.com/googlei18n/fontview		This is the same stuff we'll use in inkscape soon. The project sources are available at https://github.com/googlei18n/fontview

			On Fedora: dnf install wxGTK3-devel

			== Inkscape ==

			Linked to recent libraries, Inkscape can use "named" variations out-of-the box (i.e., one font file provides multiple styles).

			Reading of 'font-variation-settings' implemented. Needs fixing (incorrect parsing, parsing not robust against variations in white-space).

			Pango uses a different mechanism for handling ''variations'' from 'font-feature-settings'. Variations are handled in the Pango font description while features are handled by setting attributes.

			Hint: To compile and link with libraries in /usr/local execute:

			export PKG_CONFIG_PATH=/usr/local/lib/pkgconfig

			before running ''cmake''.

	== User Interface ==		== User Interface ==

	On the UI, I've been thinking of sliders as the dumb-obvious solution to select values for a variable font axes, but I also think it would be cool to think of a user-defined "palette" of varfont instances. Because you have pretty much infinite variations that can be chosen in a varfont, but you'd want to pick some and use them on your document and then be able to tweak one of the instances and then see the change affecting all places where that was used. So, a varfont can have typedesigner-specified named instances, but I think we should also offer user-defined instances. And these should show up on the font selector just like nowadays we have a drop-down for Regular/Bold/Italics. [[User:Juca\|Felipe "Juca" Sanches]] ([[User talk:Juca\|talk]])		On the UI, I've been thinking of sliders as the dumb-obvious solution to select values for a variable font axes, but I also think it would be cool to think of a user-defined "palette" of varfont instances. Because you have pretty much infinite variations that can be chosen in a varfont, but you'd want to pick some and use them on your document and then be able to tweak one of the instances and then see the change affecting all places where that was used. So, a varfont can have typedesigner-specified named instances, but I think we should also offer user-defined instances. And these should show up on the font selector just like nowadays we have a drop-down for Regular/Bold/Italics. [[User:Juca\|Felipe "Juca" Sanches]] ([[User talk:Juca\|talk]])

Juca at 03:00, 2 March 2018

2018-03-02T03:00:22Z

← Older revision		Revision as of 03:00, 2 March 2018
Line 1:		Line 1:
	~~ok. I got something good here now. I built harfbuzz and freetype from git and then I built fontview and I am studying its source code~~

	== references ==		== references ==
	=== Google's FontView proof-of-concept ===		=== Google's FontView proof-of-concept ===

Juca: /* User Interface */

2018-03-02T02:59:42Z

User Interface

← Older revision		Revision as of 02:59, 2 March 2018
Line 8:		Line 8:
	== User Interface ==		== User Interface ==

	On the UI, I've been thinking of sliders as the dumb-obvious solution to select values for a variable font axes, but I also think it would be cool to think of a user-defined "palette" of varfont instances. Because you have pretty much infinite variations that can be chosen in a varfont, but you'd want to pick some and use them on your document and then be able to tweak one of the instances and then see the change affecting all places where that was used. So, a varfont can have typedesigner-specified named instances, but I think we should also offer user-defined instances. And these should show up on the font selector just like nowadays we have a drop-down for Regular/Bold/Italics. [[User:Juca\|~~JucaBlues~~]] ([[User talk:Juca\|talk]]~~) 02:57, 2 March 2018 (UTC~~)		On the UI, I've been thinking of sliders as the dumb-obvious solution to select values for a variable font axes, but I also think it would be cool to think of a user-defined "palette" of varfont instances. Because you have pretty much infinite variations that can be chosen in a varfont, but you'd want to pick some and use them on your document and then be able to tweak one of the instances and then see the change affecting all places where that was used. So, a varfont can have typedesigner-specified named instances, but I think we should also offer user-defined instances. And these should show up on the font selector just like nowadays we have a drop-down for Regular/Bold/Italics. [[User:Juca\|Felipe "Juca" Sanches]] ([[User talk:Juca\|talk]])

Juca: Created page with "ok. I got something good here now. I built harfbuzz and freetype from git and then I built fontview and I am studying its source code == references == === Google's FontView p..."

2018-03-02T02:57:58Z

Created page with "ok. I got something good here now. I built harfbuzz and freetype from git and then I built fontview and I am studying its source code == references == === Google's FontView p..."

New page

ok. I got something good here now. I built harfbuzz and freetype from git and then I built fontview and I am studying its source code

== references ==
=== Google's FontView proof-of-concept ===
FontView is a demo program written by Google engineers to demonstrate the variable font technologies recently added to harfbuzz and freetype.
This is the same stuff we'll use in inkscape soon. The project sources are available at https://github.com/googlei18n/fontview

== User Interface ==

On the UI, I've been thinking of sliders as the dumb-obvious solution to select values for a variable font axes, but I also think it would be cool to think of a user-defined "palette" of varfont instances. Because you have pretty much infinite variations that can be chosen in a varfont, but you'd want to pick some and use them on your document and then be able to tweak one of the instances and then see the change affecting all places where that was used. So, a varfont can have typedesigner-specified named instances, but I think we should also offer user-defined instances. And these should show up on the font selector just like nowadays we have a drop-down for Regular/Bold/Italics. [[User:Juca|JucaBlues]] ([[User talk:Juca|talk]]) 02:57, 2 March 2018 (UTC)