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-rw-r--r--freetype/include/ftautoh.h52
1 files changed, 50 insertions, 2 deletions
diff --git a/freetype/include/ftautoh.h b/freetype/include/ftautoh.h
index 59191abbf..cf7b76f49 100644
--- a/freetype/include/ftautoh.h
+++ b/freetype/include/ftautoh.h
@@ -4,7 +4,7 @@
/* */
/* FreeType API for controlling the auto-hinter (specification only). */
/* */
-/* Copyright 2012, 2013 by */
+/* Copyright 2012-2015 by */
/* David Turner, Robert Wilhelm, and Werner Lemberg. */
/* */
/* This file is part of the FreeType project, and may only be used, */
@@ -300,7 +300,7 @@ FT_BEGIN_HEADER
* @description:
* *Experimental* *only*
*
- * If Freetype gets compiled with FT_CONFIG_OPTION_USE_HARFBUZZ to make
+ * If FreeType gets compiled with FT_CONFIG_OPTION_USE_HARFBUZZ to make
* the HarfBuzz library access OpenType features for getting better
* glyph coverages, this property sets the (auto-fitter) script to be
* used for the default (OpenType) script data of a font's GSUB table.
@@ -391,6 +391,54 @@ FT_BEGIN_HEADER
} FT_Prop_IncreaseXHeight;
+
+ /**************************************************************************
+ *
+ * @property:
+ * warping
+ *
+ * @description:
+ * *Experimental* *only*
+ *
+ * If FreeType gets compiled with option AF_CONFIG_OPTION_USE_WARPER to
+ * activate the warp hinting code in the auto-hinter, this property
+ * switches warping on and off.
+ *
+ * Warping only works in `light' auto-hinting mode. The idea of the
+ * code is to slightly scale and shift a glyph along the non-hinted
+ * dimension (which is usually the horizontal axis) so that as much of
+ * its segments are aligned (more or less) to the grid. To find out a
+ * glyph's optimal scaling and shifting value, various parameter
+ * combinations are tried and scored.
+ *
+ * By default, warping is off. The example below shows how to switch on
+ * warping (omitting the error handling).
+ *
+ * {
+ * FT_Library library;
+ * FT_Bool warping = 1;
+ *
+ *
+ * FT_Init_FreeType( &library );
+ *
+ * FT_Property_Set( library, "autofitter",
+ * "warping", &warping );
+ * }
+ *
+ * @note:
+ * This property can be used with @FT_Property_Get also.
+ *
+ * The warping code can also change advance widths. Have a look at the
+ * `lsb_delta' and `rsb_delta' fields in the @FT_GlyphSlotRec structure
+ * for details on improving inter-glyph distances while rendering.
+ *
+ * Since warping is a global property of the auto-hinter it is best to
+ * change its value before rendering any face. Otherwise, you should
+ * reload all faces that get auto-hinted in `light' hinting mode.
+ *
+ */
+
+
/* */