ref: 90ecac4118eb18b2f9e2f72cc0e0fdd42144bfe3
parent: 69c3516c88cf1fc9814ec70f9984072b4c3c04a0
author: Werner Lemberg <wl@gnu.org>
date: Wed Jun 30 06:23:42 EDT 2021
Update `CHANGES` file; other minor doc fixes.
--- a/docs/CHANGES
+++ b/docs/CHANGES
@@ -79,13 +79,34 @@
- Improved Meson build support for the library.
- - Meson support to build The FreeType demo programs.
+ - Meson support to build the FreeType demo programs.
- - `ttdebug` didn't show changed point coordinates (bug introduced in
- version 2.10.3).
+ - A new demo program `ftsdf` is available to display Signed Distance
+ Fields of glyphs.
- - The graphical demos now work better in native color depth on win32
- and x11.
+ - The `ftlint` demo program has been extended to do more testing of
+ its input. In particular, it can display horizontal and vertical
+ acutances for quality assessment, together with computing MD5
+ checksums of rendered glyphs.
+
+ [The acutance measures how sharply the pixel coverage changes at
+ glyph edges. For monochrome bitmaps, it is always 2.0 in either
+ X or Y direction. For anti-aliased bitmaps, it depends on the
+ hinting and the shape of a glyph and might approach or even reach
+ value 2.0 for glyphs like 'I', 'L', '+', '-', or '=', while it
+ might be lower for glyphs like 'O', 'S', or 'W'.]
+
+ - The `ttdebug` demo program didn't show changed point coordinates
+ (bug introduced in version 2.10.3).
+
+ - It is now possible to adjust the axis increment for variable fonts
+ in the `ftmulti` demo program.
+
+ - It is now possible to change the hinting engine in the `ftstring`
+ demo program.
+
+ - The graphical demo programs work better now in native color depth
+ on win32 and x11.
======================================================================
--- a/docs/INSTALL.ANY
+++ b/docs/INSTALL.ANY
@@ -73,6 +73,7 @@
formats)
src/raster/raster.c -- monochrome rasterizer
+ src/sdf/sdf.c -- Signed Distance Field driver
src/smooth/smooth.c -- anti-aliasing rasterizer
-- auxiliary modules (optional)
--- a/include/freetype/freetype.h
+++ b/include/freetype/freetype.h
@@ -3445,7 +3445,8 @@
*
* which is known as the OVER operator.
*
- * To correctly composite an antialiased pixel of a glyph onto a surface,
+ * To correctly composite an anti-aliased pixel of a glyph onto a
+ * surface,
*
* 1. take the foreground and background colors (e.g., in sRGB space)
* and apply gamma to get them in a linear space,
--- a/include/freetype/ftdriver.h
+++ b/include/freetype/ftdriver.h
@@ -84,15 +84,15 @@
* @properties section.
*
*
- * **Hinting and antialiasing principles of the new engine**
+ * **Hinting and anti-aliasing principles of the new engine**
*
* The rasterizer is positioning horizontal features (e.g., ascender
* height & x-height, or crossbars) on the pixel grid and minimizing the
- * amount of antialiasing applied to them, while placing vertical
+ * amount of anti-aliasing applied to them, while placing vertical
* features (vertical stems) on the pixel grid without hinting, thus
* representing the stem position and weight accurately. Sometimes the
* vertical stems may be only partially black. In this context,
- * 'antialiasing' means that stems are not positioned exactly on pixel
+ * 'anti-aliasing' means that stems are not positioned exactly on pixel
* borders, causing a fuzzy appearance.
*
* There are two principles behind this approach.
@@ -108,7 +108,7 @@
* sizes are comparable to kerning values and thus would be noticeable
* (and distracting) while reading if hinting were applied.
*
- * One of the reasons to not hint horizontally is antialiasing for LCD
+ * One of the reasons to not hint horizontally is anti-aliasing for LCD
* screens: The pixel geometry of modern displays supplies three vertical
* subpixels as the eye moves horizontally across each visible pixel. On
* devices where we can be certain this characteristic is present a
@@ -116,7 +116,7 @@
* weight. In Western writing systems this turns out to be the more
* critical direction anyway; the weights and spacing of vertical stems
* (see above) are central to Armenian, Cyrillic, Greek, and Latin type
- * designs. Even when the rasterizer uses greyscale antialiasing instead
+ * designs. Even when the rasterizer uses greyscale anti-aliasing instead
* of color (a necessary compromise when one doesn't know the screen
* characteristics), the unhinted vertical features preserve the design's
* weight and spacing much better than aliased type would.
--- a/src/sdf/ftsdfrend.c
+++ b/src/sdf/ftsdfrend.c
@@ -290,7 +290,7 @@
}
/* preset the bitmap using the glyph's outline; */
- /* the sdf bitmap is similar to an antialiased bitmap */
+ /* the sdf bitmap is similar to an anti-aliased bitmap */
/* with a slightly bigger size and different pixel mode */
if ( ft_glyphslot_preset_bitmap( slot, FT_RENDER_MODE_NORMAL, origin ) )
{