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src/java.desktop/share/native/libfreetype/include/freetype/ftstroke.h
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@@ -2,11 +2,11 @@
*
* ftstroke.h
*
* FreeType path stroker (specification).
*
- * Copyright (C) 2002-2019 by
+ * Copyright (C) 2002-2020 by
* David Turner, Robert Wilhelm, and Werner Lemberg.
*
* This file is part of the FreeType project, and may only be used,
* modified, and distributed under the terms of the FreeType project
* license, LICENSE.TXT. By continuing to use, modify, or distribute
@@ -112,26 +112,23 @@
* with a straight line between the outer corners of each stroke.
*
* FT_STROKER_LINEJOIN_MITER_FIXED ::
* Used to render mitered line joins, with fixed bevels if the miter
* limit is exceeded. The outer edges of the strokes for the two
- * segments are extended until they meet at an angle. If the segments
- * meet at too sharp an angle (such that the miter would extend from
- * the intersection of the segments a distance greater than the product
- * of the miter limit value and the border radius), then a bevel join
- * (see above) is used instead. This prevents long spikes being
- * created. `FT_STROKER_LINEJOIN_MITER_FIXED` generates a miter line
- * join as used in PostScript and PDF.
+ * segments are extended until they meet at an angle. A bevel join
+ * (see above) is used if the segments meet at too sharp an angle and
+ * the outer edges meet beyond a distance corresponding to the meter
+ * limit. This prevents long spikes being created.
+ * `FT_STROKER_LINEJOIN_MITER_FIXED` generates a miter line join as
+ * used in PostScript and PDF.
*
* FT_STROKER_LINEJOIN_MITER_VARIABLE ::
* FT_STROKER_LINEJOIN_MITER ::
* Used to render mitered line joins, with variable bevels if the miter
- * limit is exceeded. The intersection of the strokes is clipped at a
- * line perpendicular to the bisector of the angle between the strokes,
- * at the distance from the intersection of the segments equal to the
- * product of the miter limit value and the border radius. This
- * prevents long spikes being created.
+ * limit is exceeded. The intersection of the strokes is clipped
+ * perpendicularly to the bisector, at a distance corresponding to
+ * the miter limit. This prevents long spikes being created.
* `FT_STROKER_LINEJOIN_MITER_VARIABLE` generates a mitered line join
* as used in XPS. `FT_STROKER_LINEJOIN_MITER` is an alias for
* `FT_STROKER_LINEJOIN_MITER_VARIABLE`, retained for backward
* compatibility.
*/
@@ -294,16 +291,21 @@
*
* line_join ::
* The line join style.
*
* miter_limit ::
- * The miter limit for the `FT_STROKER_LINEJOIN_MITER_FIXED` and
- * `FT_STROKER_LINEJOIN_MITER_VARIABLE` line join styles, expressed as
- * 16.16 fixed-point value.
+ * The maximum reciprocal sine of half-angle at the miter join,
+ * expressed as 16.16 fixed point value.
*
* @note:
- * The radius is expressed in the same units as the outline coordinates.
+ * The `radius` is expressed in the same units as the outline
+ * coordinates.
+ *
+ * The `miter_limit` multiplied by the `radius` gives the maximum size
+ * of a miter spike, at which it is clipped for
+ * @FT_STROKER_LINEJOIN_MITER_VARIABLE or replaced with a bevel join for
+ * @FT_STROKER_LINEJOIN_MITER_FIXED.
*
* This function calls @FT_Stroker_Rewind automatically.
*/
FT_EXPORT( void )
FT_Stroker_Set( FT_Stroker stroker,
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