ref: 97c09a803eb6cd44456e0251529db2ae96a019f8
parent: 5cf01aa2b26727abd97ef202a3687cd7a43819c3
author: Moazin Khatti <[email protected]>
date: Sat Dec 25 14:55:58 EST 2021
Add `FT_Glyph` support for OT-SVG glyphs. * include/freetype/ftglyph.h (FT_SvgGlyphRec, FT_SvgGlyph): New structure. * src/base/ftglyph.c: Include `otsvg.h`. (ft_svg_glyph_init, ft_svg_glyph_done, ft_svg_glyph_copy, ft_svg_glyph_transform, ft_svg_glyph_prepare): New function. (ft_svg_glyph_class): New class. (FT_New_Glyph, FT_Glyph_To_Bitmap): Updated to handle OT-SVG glyphs. * src/base/ftglyph.h: Updated.
--- a/include/freetype/ftglyph.h
+++ b/include/freetype/ftglyph.h
@@ -126,7 +126,7 @@
*
* @description:
* A handle to an object used to model a bitmap glyph image. This is a
- * sub-class of @FT_Glyph, and a pointer to @FT_BitmapGlyphRec.
+ * 'sub-class' of @FT_Glyph, and a pointer to @FT_BitmapGlyphRec.
*/
typedef struct FT_BitmapGlyphRec_* FT_BitmapGlyph;
@@ -142,7 +142,7 @@
*
* @fields:
* root ::
- * The root @FT_Glyph fields.
+ * The root fields of @FT_Glyph.
*
* left ::
* The left-side bearing, i.e., the horizontal distance from the
@@ -220,6 +220,92 @@
FT_Outline outline;
} FT_OutlineGlyphRec;
+
+
+ /**************************************************************************
+ *
+ * @type:
+ * FT_SvgGlyph
+ *
+ * @description:
+ * A handle to an object used to model an SVG glyph. This is a
+ * 'sub-class' of @FT_Glyph, and a pointer to @FT_SvgGlyphRec.
+ *
+ * @since:
+ * 2.12
+ */
+ typedef struct FT_SvgGlyphRec_* FT_SvgGlyph;
+
+
+ /**************************************************************************
+ *
+ * @struct:
+ * FT_SvgGlyphRec
+ *
+ * @description:
+ * A structure used for OT-SVG glyphs. This is a 'sub-class' of
+ * @FT_GlyphRec.
+ *
+ * @fields:
+ * root ::
+ * The root @FT_GlyphRec fields.
+ *
+ * svg_document ::
+ * A pointer to the SVG document.
+ *
+ * svg_document_length ::
+ * The length of `svg_document`.
+ *
+ * glyph_index ::
+ * The index of the glyph to be rendered.
+ *
+ * metrics ::
+ * A metrics object storing the size information.
+ *
+ * units_per_EM ::
+ * The size of the EM square.
+ *
+ * start_glyph_id ::
+ * The first glyph ID in the glyph range covered by this document.
+ *
+ * end_glyph_id ::
+ * The last glyph ID in the glyph range covered by this document.
+ *
+ * transform ::
+ * A 2x2 transformation matrix to apply to the glyph while rendering
+ * it.
+ *
+ * delta ::
+ * Translation to apply to the glyph while rendering.
+ *
+ * @note:
+ * The Glyph Management API requires @FT_Glyph or its 'sub-class' to have
+ * all the information needed to completely define the glyph's rendering.
+ * Outline-based glyphs can directly apply transformations to the outline
+ * but this is not possible for an SVG document that hasn't been parsed.
+ * Therefore, the transformation is stored along with the document. In
+ * the absence of a 'ViewBox' or 'Width'/'Height' attribute, the size of
+ * the ViewPort should be assumed to be 'units_per_EM'.
+ */
+ typedef struct FT_SvgGlyphRec_
+ {+ FT_GlyphRec root;
+
+ FT_Byte* svg_document;
+ FT_ULong svg_document_length;
+
+ FT_UInt glyph_index;
+
+ FT_Size_Metrics metrics;
+ FT_UShort units_per_EM;
+
+ FT_UShort start_glyph_id;
+ FT_UShort end_glyph_id;
+
+ FT_Matrix transform;
+ FT_Vector delta;
+
+ } FT_SvgGlyphRec;
/**************************************************************************
--- a/src/base/ftbase.h
+++ b/src/base/ftbase.h
@@ -28,6 +28,7 @@
FT_DECLARE_GLYPH( ft_bitmap_glyph_class )
FT_DECLARE_GLYPH( ft_outline_glyph_class )
+ FT_DECLARE_GLYPH( ft_svg_glyph_class )
#ifdef FT_CONFIG_OPTION_MAC_FONTS
--- a/src/base/ftglyph.c
+++ b/src/base/ftglyph.c
@@ -34,6 +34,7 @@
#include <freetype/ftoutln.h>
#include <freetype/ftbitmap.h>
#include <freetype/internal/ftobjs.h>
+#include <freetype/otsvg.h>
#include "ftbase.h"
@@ -277,9 +278,243 @@
)
+#ifdef FT_CONFIG_OPTION_SVG
+
/*************************************************************************/
/*************************************************************************/
/**** ****/
+ /**** FT_SvgGlyph support ****/
+ /**** ****/
+ /*************************************************************************/
+ /*************************************************************************/
+
+
+ FT_CALLBACK_DEF( FT_Error )
+ ft_svg_glyph_init( FT_Glyph svg_glyph,
+ FT_GlyphSlot slot )
+ {+ FT_ULong doc_length;
+ FT_SVG_Document document;
+ FT_SvgGlyph glyph = (FT_SvgGlyph)svg_glyph;
+
+ FT_Error error = FT_Err_Ok;
+ FT_Memory memory = FT_GLYPH( glyph )->library->memory;
+
+
+ if ( slot->format != FT_GLYPH_FORMAT_SVG )
+ {+ error = FT_THROW( Invalid_Glyph_Format );
+ goto Exit;
+ }
+
+ if ( slot->other == NULL )
+ {+ error = FT_THROW( Invalid_Slot_Handle );
+ goto Exit;
+ }
+
+ document = (FT_SVG_Document)slot->other;
+
+ if ( document->svg_document_length == 0 )
+ {+ error = FT_THROW( Invalid_Slot_Handle );
+ goto Exit;
+ }
+
+ /* allocate a new document */
+ doc_length = document->svg_document_length;
+ if ( FT_QALLOC( glyph->svg_document, doc_length ) )
+ goto Exit;
+ glyph->svg_document_length = doc_length;
+
+ glyph->glyph_index = slot->glyph_index;
+
+ glyph->metrics = document->metrics;
+ glyph->units_per_EM = document->units_per_EM;
+
+ glyph->start_glyph_id = document->start_glyph_id;
+ glyph->end_glyph_id = document->end_glyph_id;
+
+ glyph->transform = document->transform;
+ glyph->delta = document->delta;
+
+ /* copy the document into glyph */
+ FT_MEM_COPY( glyph->svg_document, document->svg_document, doc_length );
+
+ Exit:
+ return error;
+ }
+
+
+ FT_CALLBACK_DEF( void )
+ ft_svg_glyph_done( FT_Glyph svg_glyph )
+ {+ FT_SvgGlyph glyph = (FT_SvgGlyph)svg_glyph;
+ FT_Memory memory = svg_glyph->library->memory;
+
+
+ /* just free the memory */
+ FT_FREE( glyph->svg_document );
+ }
+
+
+ FT_CALLBACK_DEF( FT_Error )
+ ft_svg_glyph_copy( FT_Glyph svg_source,
+ FT_Glyph svg_target )
+ {+ FT_SvgGlyph source = (FT_SvgGlyph)svg_source;
+ FT_SvgGlyph target = (FT_SvgGlyph)svg_target;
+
+ FT_Error error = FT_Err_Ok;
+ FT_Memory memory = FT_GLYPH( source )->library->memory;
+
+
+ if ( svg_source->format != FT_GLYPH_FORMAT_SVG )
+ {+ error = FT_THROW( Invalid_Glyph_Format );
+ goto Exit;
+ }
+
+ if ( source->svg_document_length == 0 )
+ {+ error = FT_THROW( Invalid_Slot_Handle );
+ goto Exit;
+ }
+
+ target->glyph_index = source->glyph_index;
+
+ target->svg_document_length = source->svg_document_length;
+
+ target->metrics = source->metrics;
+ target->units_per_EM = source->units_per_EM;
+
+ target->start_glyph_id = source->start_glyph_id;
+ target->end_glyph_id = source->end_glyph_id;
+
+ target->transform = source->transform;
+ target->delta = source->delta;
+
+ /* allocate space for the SVG document */
+ if ( FT_QALLOC( target->svg_document, target->svg_document_length ) )
+ goto Exit;
+
+ /* copy the document */
+ FT_MEM_COPY( target->svg_document,
+ source->svg_document,
+ target->svg_document_length );
+
+ Exit:
+ return error;
+ }
+
+
+ FT_CALLBACK_DEF( void )
+ ft_svg_glyph_transform( FT_Glyph svg_glyph,
+ const FT_Matrix* _matrix,
+ const FT_Vector* _delta )
+ {+ FT_SvgGlyph glyph = (FT_SvgGlyph)svg_glyph;
+ FT_Matrix* matrix = (FT_Matrix*)_matrix;
+ FT_Vector* delta = (FT_Vector*)_delta;
+
+ FT_Matrix tmp_matrix;
+ FT_Vector tmp_delta;
+
+ FT_Matrix a, b;
+ FT_Pos x, y;
+
+
+ if ( !matrix )
+ {+ tmp_matrix.xx = 0x10000;
+ tmp_matrix.xy = 0;
+ tmp_matrix.yx = 0;
+ tmp_matrix.yy = 0x10000;
+
+ matrix = &tmp_matrix;
+ }
+
+ if ( !delta )
+ {+ tmp_delta.x = 0;
+ tmp_delta.y = 0;
+
+ delta = &tmp_delta;
+ }
+
+ a = glyph->transform;
+ b = *matrix;
+ FT_Matrix_Multiply( &b, &a );
+
+ x = ADD_LONG( ADD_LONG( FT_MulFix( matrix->xx, glyph->delta.x ),
+ FT_MulFix( matrix->xy, glyph->delta.y ) ),
+ delta->x );
+ y = ADD_LONG( ADD_LONG( FT_MulFix( matrix->yx, glyph->delta.x ),
+ FT_MulFix( matrix->yy, glyph->delta.y ) ),
+ delta->y );
+
+ glyph->delta.x = x;
+ glyph->delta.y = y;
+
+ glyph->transform = a;
+ }
+
+
+ FT_CALLBACK_DEF( FT_Error )
+ ft_svg_glyph_prepare( FT_Glyph svg_glyph,
+ FT_GlyphSlot slot )
+ {+ FT_SvgGlyph glyph = (FT_SvgGlyph)svg_glyph;
+
+ FT_Error error = FT_Err_Ok;
+ FT_Memory memory = svg_glyph->library->memory;
+
+ FT_SVG_Document document;
+
+
+ if ( FT_NEW( document ) )
+ return error;
+
+ document->svg_document = glyph->svg_document;
+ document->svg_document_length = glyph->svg_document_length;
+
+ document->metrics = glyph->metrics;
+ document->units_per_EM = glyph->units_per_EM;
+
+ document->start_glyph_id = glyph->start_glyph_id;
+ document->end_glyph_id = glyph->end_glyph_id;
+
+ document->transform = glyph->transform;
+ document->delta = glyph->delta;
+
+ slot->format = FT_GLYPH_FORMAT_SVG;
+ slot->glyph_index = glyph->glyph_index;
+ slot->other = document;
+
+ return error;
+ }
+
+
+ FT_DEFINE_GLYPH(
+ ft_svg_glyph_class,
+
+ sizeof ( FT_SvgGlyphRec ),
+ FT_GLYPH_FORMAT_SVG,
+
+ ft_svg_glyph_init, /* FT_Glyph_InitFunc glyph_init */
+ ft_svg_glyph_done, /* FT_Glyph_DoneFunc glyph_done */
+ ft_svg_glyph_copy, /* FT_Glyph_CopyFunc glyph_copy */
+ ft_svg_glyph_transform, /* FT_Glyph_TransformFunc glyph_transform */
+ NULL, /* FT_Glyph_GetBBoxFunc glyph_bbox */
+ ft_svg_glyph_prepare /* FT_Glyph_PrepareFunc glyph_prepare */
+ )
+
+#endif /* FT_CONFIG_OPTION_SVG */
+
+
+ /*************************************************************************/
+ /*************************************************************************/
+ /**** ****/
/**** FT_Glyph class and API ****/
/**** ****/
/*************************************************************************/
@@ -377,6 +612,12 @@
else if ( format == FT_GLYPH_FORMAT_OUTLINE )
clazz = &ft_outline_glyph_class;
+#ifdef FT_CONFIG_OPTION_SVG
+ /* if it is an SVG glyph */
+ else if ( format == FT_GLYPH_FORMAT_SVG )
+ clazz = &ft_svg_glyph_class;
+#endif
+
else
{/* try to find a renderer that supports the glyph image format */
@@ -594,6 +835,16 @@
error = clazz->glyph_prepare( glyph, &dummy );
if ( !error )
error = FT_Render_Glyph_Internal( glyph->library, &dummy, render_mode );
+
+#ifdef FT_CONFIG_OPTION_SVG
+ if ( clazz == &ft_svg_glyph_class )
+ {+ FT_Memory memory = library->memory;
+
+
+ FT_FREE( dummy.other );
+ }
+#endif
#if 1
if ( !destroy && origin )