ref: b7e18efcd2d6a71ec1a4bdf167f78d707ac91593
parent: 318f3befc67e026037da33fb7b5b9a22d567df9a
author: David Turner <[email protected]>
date: Wed Jun 26 18:05:05 EDT 2002
adding path stroker component (first steps)
--- /dev/null
+++ b/include/freetype/ftstroker.h
@@ -1,0 +1,144 @@
+#ifndef __FT_STROKER_H__
+#define __FT_STROKER_H__
+
+#include <ft2build.h>
+#include FT_OUTLINE_H
+
+FT_BEGIN_HEADER
+
+/**************************************************************
+ *
+ * @type: FT_Stroker
+ *
+ * @description:
+ * opaque handler to a path stroker object
+ */
+ typedef struct FT_StrokerRec_* FT_Stroker;
+
+
+/**************************************************************
+ *
+ * @enum: FT_Stroker_LineJoin
+ *
+ * @description:
+ * these values determine how two joining lines are rendered
+ * in a stroker.
+ *
+ * @values:
+ * FT_STROKER_LINEJOIN_ROUND ::
+ * used to render rounded line joins. circular arcs are used
+ * to join two lines smoothly
+ *
+ * FT_STROKER_LINEJOIN_BEVEL ::
+ * used to render beveled line joins; i.e. the two joining lines
+ * are extended until they intersect
+ *
+ * FT_STROKER_LINEJOIN_MITER ::
+ * same as beveled rendering, except that an additional line
+ * break is added if the angle between the two joining lines
+ * is too closed (this is useful to avoid unpleasant spikes
+ * in beveled rendering).
+ */
+ typedef enum
+ {+ FT_STROKER_LINEJOIN_ROUND = 0,
+ FT_STROKER_LINEJOIN_BEVEL,
+ FT_STROKER_LINEJOIN_MITER
+
+ } FT_Stroker_LineJoin;
+
+
+/**************************************************************
+ *
+ * @enum: FT_Stroker_LineCap
+ *
+ * @description:
+ * these values determine how the end of opened sub-paths are
+ * rendered in a stroke
+ *
+ * @values:
+ * FT_STROKER_LINECAP_BUTT ::
+ * the end of lines is rendered as a full stop on the last
+ * point itself
+ *
+ * FT_STROKER_LINECAP_ROUND ::
+ * the end of lines is rendered as a half-circle around the
+ * last point
+ *
+ * FT_STROKER_LINEJOIN_MITER ::
+ * the end of lines is rendered as a square around the
+ * last point
+ */
+ typedef enum
+ {+ FT_STROKER_LINECAP_BUTT = 0,
+ FT_STROKER_LINECAP_ROUND,
+ FT_STROKER_LINECAP_SQUARE
+
+ } FT_Stroker_LineCap;
+
+
+ FT_EXPORT( FT_Error )
+ FT_Stroker_New( FT_Memory memory,
+ FT_Stroker *astroker );
+
+ FT_EXPORT( void )
+ FT_Stroker_Set( FT_Stroker stroker,
+ FT_Fixed radius,
+ FT_Stroker_LineCap line_cap,
+ FT_Stroker_LineJoin line_join,
+ FT_Fixed miter_limit );
+
+ FT_EXPORT( FT_Error )
+ FT_Stroker_BeginSubPath( FT_Stroker stroker,
+ FT_Pos x,
+ FT_Pos y,
+ FT_Bool open );
+
+ FT_EXPORT( FT_Error )
+ FT_Stroker_EndSubPath( FT_Stroker stroker );
+
+
+ FT_EXPORT( FT_Error )
+ FT_Stroker_LineTo( FT_Stroker stroker,
+ FT_Pos to_x,
+ FT_Pos to_y );
+
+ FT_EXPORT( FT_Error )
+ FT_Stroker_ConicTo( FT_Stroker stroker,
+ FT_Pos control_x,
+ FT_Pos control_y,
+ FT_Pos to_x,
+ FT_Pos to_y );
+
+ FT_EXPORT( FT_Error )
+ FT_Stroker_CubicTo( FT_Stroker stroker,
+ FT_Pos control1_x,
+ FT_Pos control1_y,
+ FT_Pos control2_x,
+ FT_Pos control2_y,
+ FT_Pos to_x,
+ FT_Pos to_y );
+
+
+ FT_EXPORT( FT_Error )
+ FT_Stroker_GetCounts( FT_Stroker stroker,
+ FT_UInt *anum_points,
+ FT_UInt *anum_contours );
+
+ FT_EXPORT( void )
+ FT_Stroker_Export( FT_Stroker stroker,
+ FT_Outliner* outline );
+
+ FT_EXPORT( void )
+ FT_Stroker_Done( FT_Stroker stroker );
+
+
+ FT_EXPORT( FT_Error )
+ FT_Stroker_ParseOutline( FT_Stroker stroker,
+ FT_Outline* outline,
+ FT_Bool opened );
+
+FT_END_HEADER
+
+#endif /* __FT_STROKER_H__ */
--- a/include/freetype/fttrigon.h
+++ b/include/freetype/fttrigon.h
@@ -176,6 +176,27 @@
/*************************************************************************/
/* */
/* @function: */
+ /* FT_Angle_Diff */
+ /* */
+ /* @description: */
+ /* Returns the difference between two angles. The result is always */
+ /* constrained to the ]-PI..PI] interval */
+ /* */
+ /* @input: */
+ /* angle1 :: first angle */
+ /* angle2 :: second angle */
+ /* */
+ /* @return: */
+ /* contrainted value of 'value2-value1' */
+ /* */
+ FT_EXPORT_DEF( FT_Angle )
+ FT_Angle_Dif( FT_Angle angle1,
+ FT_Angle angle2 );
+
+
+ /*************************************************************************/
+ /* */
+ /* @function: */
/* FT_Vector_Unit */
/* */
/* @description: */
--- /dev/null
+++ b/src/base/ftstroker.c
@@ -1,0 +1,290 @@
+#include <ft2build.h>
+#include FT_STROKER_H
+#include FT_TRIGONOMETRY_H
+
+ /***************************************************************************/
+ /***************************************************************************/
+ /***** *****/
+ /***** STROKE BORDERS *****/
+ /***** *****/
+ /***************************************************************************/
+ /***************************************************************************/
+
+ typedef enum
+ {+ FT_STROKE_TAG_ON = 1, /* on-curve point */
+ FT_STROKE_TAG_CUBIC = 2, /* cubic off-point */
+ FT_STROKE_TAG_BEGIN = 4, /* sub-path start */
+ FT_STROKE_TAG_END = 8 /* sub-path end */
+
+ } FT_StrokeTags;
+
+
+ typedef struct FT_StrokeBorderRec_
+ {+ FT_UInt num_points;
+ FT_UInt max_points;
+ FT_Vector* points;
+ FT_Byte* tags;
+ FT_Bool movable;
+ FT_Int start; /* index of current sub-path start point */
+ FT_Memory memory;
+
+ } FT_StrokeBorderRec, *FT_StrokeBorder;
+
+
+ static FT_Error
+ ft_stroke_border_grow( FT_StrokeBorder border,
+ FT_UInt new_points )
+ {+ FT_UInt old_max = border->max_points;
+ FT_UInt new_max = border->num_points + new_points;
+ FT_Error error = 0;
+
+ if ( new_max > old_max )
+ {+ FT_UInt cur_max = old_max;
+ FT_Memory memory =
+
+ while ( cur_max < new_max )
+ cur_max += (cur_max >> 1) + 16;
+
+ if ( FT_RENEW_ARRAY( border->points, old_max, cur_max ) ||
+ FT_RENEW_ARRAY( border->tags, old_max, cur_max ) )
+ goto Exit;
+
+ border->max_points = cur_max;
+ }
+ Exit:
+ return error;
+ }
+
+ static void
+ ft_stroke_border_close( FT_StrokeBorder border )
+ {+ FT_ASSERT( border->start >= 0 );
+
+ border->tags[ border->start ] |= FT_STROKE_TAG_BEGIN;
+ border->tags[ border->num_points-1 ] |= FT_STROKE_TAG_END;
+
+ border->start = -1;
+ }
+
+
+ static FT_Error
+ ft_stroke_border_lineto( FT_StrokeBorder border,
+ FT_Vector* to )
+ {+ FT_Error error;
+
+ FT_ASSERT( border->start >= 0 );
+
+ error = ft_stroker_border_grow( border, 1 );
+ if (!error)
+ {+ FT_Vector* vec = border->points + border->num_points;
+ FT_Byte* tag = border->tags + border->num_points;
+
+ vec[0] = *to;
+ tag[0] = FT_STROKE_TAG_ON;
+
+ border->num_points += 1;
+ }
+ return error;
+ }
+
+
+ static FT_Error
+ ft_stroke_border_conicto( FT_StrokeBorder border,
+ FT_Vector* control,
+ FT_Vector* to )
+ {+ FT_Error error;
+
+ FT_ASSERT( border->start >= 0 );
+
+ error = ft_stroker_border_grow( border, 2 );
+ if (!error)
+ {+ FT_Vector* vec = border->points + border->num_points;
+ FT_Byte* tag = border->tags + border->num_points;
+
+ vec[0] = *control;
+ vec[1] = *to;
+
+ tag[0] = 0;
+ tag[1] = FT_STROKE_TAG_ON;
+
+ border->num_points += 2;
+ }
+ return error;
+ }
+
+
+ static FT_Error
+ ft_stroke_border_cubicto( FT_StrokeBorder border,
+ FT_Vector* control1,
+ FT_Vector* control2,
+ FT_Vector* to )
+ {+ FT_Error error;
+
+ FT_ASSERT( border->start >= 0 );
+
+ error = ft_stroker_border_grow( border, 3 );
+ if (!error)
+ {+ FT_Vector* vec = border->points + border->num_points;
+ FT_Byte* tag = border->tags + border->num_points;
+
+ vec[0] = *control1;
+ vec[1] = *control2;
+ vec[2] = *to;
+
+ tag[0] = FT_STROKE_TAG_CUBIC;
+ tag[1] = FT_STROKE_TAG_CUBIC;
+ tag[2] = FT_STROKE_TAG_ON;
+
+ border->num_points += 3;
+ }
+ return error;
+ }
+
+
+ static FT_Error
+ ft_stroke_border_moveto( FT_StrokeBorder border,
+ FT_Vector* to )
+ {+ FT_Error error;
+
+ /* close current open path if any ? */
+ if ( border->start >= 0 )
+ ft_stroke_border_close( border );
+
+ border->start = border->num_points;
+
+ return ft_stroke_border_lineto( border, to );
+ }
+
+
+ static void
+ ft_stroke_border_init( FT_StrokeBorder border,
+ FT_Memory memory )
+ {+ border->memory = memory;
+ border->points = NULL;
+ border->tags = NULL;
+
+ border->num_points = 0;
+ border->max_points = 0;
+ border->start = -1;
+ }
+
+
+ static void
+ ft_stroke_border_reset( FT_StrokeBorder border )
+ {+ border->num_points = 0;
+ border->start = -1;
+ }
+
+
+ static void
+ ft_stroke_border_done( FT_StrokeBorder border )
+ {+ memory = border->memory;
+
+ FT_FREE( border->points );
+ FT_FREE( border->tags );
+
+ border->num_points = 0;
+ border->max_points = 0;
+ border->start = -1;
+ }
+
+
+ /***************************************************************************/
+ /***************************************************************************/
+ /***** *****/
+ /***** STROKER *****/
+ /***** *****/
+ /***************************************************************************/
+ /***************************************************************************/
+
+#define FT_SIDE_TO_ROTATE(s) (FT_PI2 - (s)*FT_PI)
+
+ typedef struct FT_StrokerRec_
+ {+ FT_Angle angle_in;
+ FT_Angle angle_out;
+ FT_Vector center;
+ FT_Bool first_point;
+ FT_Bool subpath_open;
+ FT_Angle subpath_angle;
+ FT_Vector subpath_start;
+
+ FT_Stroker_LineCap line_cap;
+ FT_Stroker_LineJoin line_join;
+ FT_Fixed miter_limit;
+ FT_Fixed radius;
+
+ FT_StrokeBorderRec borders[2];
+ FT_Memory memory;
+
+ } FT_StrokerRec;
+
+
+ FT_EXPORT_DEF( FT_Error )
+ FT_Stroker_New( FT_Memory memory,
+ FT_Stroker *astroker )
+ {+ FT_Error error;
+ FT_Stroker stroker;
+
+ if ( !FT_NEW( stroker ) )
+ {+ stroker->memory = memory;
+
+ ft_stroke_border_init( &stroker->borders[0], memory );
+ ft_stroke_border_init( &stroker->borders[1], memory );
+ }
+ *astroker = stroker;
+ return error;
+ }
+
+
+ FT_EXPORT_DEF( void )
+ FT_Stroker_Set( FT_Stroker stroker,
+ FT_Fixed radius,
+ FT_Stroker_LineCap line_cap,
+ FT_Stroker_LineJoin line_join,
+ FT_Fixed miter_limit )
+ {+ stroker->radius = radius;
+ stroker->line_cap = line_cap;
+ stroker->line_join = line_join;
+ stroker->miter_limit = miter_limit;
+
+ ft_stroke_border_reset( &stroker->borders[0] );
+ ft_stroke_border_reset( &stroker->borders[1] );
+ }
+
+
+ FT_EXPORT( void )
+ FT_Stroker_Done( FT_Stroker stroker )
+ {+ if ( stroker )
+ {+ FT_Memory memory = stroker->memory;
+
+ ft_stroke_border_done( &stroker->borders[0] );
+ ft_stroke_border_done( &stroker->borders[1] );
+
+ stroker->memory = NULL;
+ FT_FREE( stroker );
+ }
+ }
+
+
+
+
\ No newline at end of file
--- a/src/base/fttrigon.c
+++ b/src/base/fttrigon.c
@@ -451,4 +451,21 @@
}
+ /* documentation is in fttrigon.h */
+
+ FT_EXPORT_DEF( FT_Angle )
+ FT_Angle_Dif( FT_Angle angle1,
+ FT_Angle angle2 )
+ {+ FT_Angle delta = angle2 - angle1;
+
+ delta %= FT_ANGLE_2PI;
+
+ if ( delta > FT_ANGLE_PI )
+ delta -= FT_ANGLE_2PI;
+
+ return delta;
+ }
+
+
/* END */