693 lines
18 KiB
C
693 lines
18 KiB
C
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#include <freetype/internal/ftobjs.h>
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#include <freetype/internal/ftdebug.h>
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#include <freetype/ftlist.h>
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#include "ftsdf.h"
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#include "ftsdferrs.h"
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/**************************************************************************
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*
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* typedefs
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*
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*/
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typedef FT_Vector FT_26D6_Vec; /* with 26.6 fixed point components */
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typedef FT_Vector FT_16D16_Vec; /* with 16.16 fixed point components */
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/**************************************************************************
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*
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* structures and enums
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*
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*/
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typedef struct SDF_TRaster_
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{
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FT_Memory memory; /* used internally to allocate memory */
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} SDF_TRaster;
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/* enumeration of all the types of curve present in vector fonts */
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typedef enum SDF_Edge_Type_
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{
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SDF_EDGE_UNDEFINED = 0, /* undefined, used to initialize */
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SDF_EDGE_LINE = 1, /* straight line segment */
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SDF_EDGE_CONIC = 2, /* second order bezier curve */
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SDF_EDGE_CUBIC = 3 /* third order bezier curve */
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} SDF_Edge_Type;
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/* represent a single edge in a contour */
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typedef struct SDF_Edge_
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{
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FT_26D6_Vec start_pos; /* start position of the edge */
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FT_26D6_Vec end_pos; /* end position of the edge */
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FT_26D6_Vec control_a; /* first control point of a bezier curve */
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FT_26D6_Vec control_b; /* second control point of a bezier curve */
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SDF_Edge_Type edge_type; /* edge identifier */
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} SDF_Edge;
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/* A contour represent a set of edges which make a closed */
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/* loop. */
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typedef struct SDF_Contour_
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{
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FT_26D6_Vec last_pos; /* end position of the last edge */
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FT_ListRec edges; /* list of all edges in the contour */
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} SDF_Contour;
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/* Represent a set a contours which makes up a complete */
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/* glyph outline. */
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typedef struct SDF_Shape_
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{
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FT_Memory memory; /* used internally to allocate memory */
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FT_ListRec contours; /* list of all contours in the outline */
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} SDF_Shape;
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/**************************************************************************
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*
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* constants, initializer and destructor
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*
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*/
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static
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const FT_Vector zero_vector = { 0, 0 };
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static
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const SDF_Edge null_edge = { { 0, 0 }, { 0, 0 },
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{ 0, 0 }, { 0, 0 },
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SDF_EDGE_UNDEFINED };
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static
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const SDF_Contour null_contour = { { 0, 0 }, { NULL, NULL } };
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static
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const SDF_Shape null_shape = { NULL, { NULL, NULL } };
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/* Creates a new `SDF_Edge' on the heap and assigns the `edge' */
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/* pointer to the newly allocated memory. */
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static FT_Error
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sdf_edge_new( FT_Memory memory,
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SDF_Edge** edge )
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{
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FT_Error error = FT_Err_Ok;
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SDF_Edge* ptr = NULL;
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if ( !memory || !edge )
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{
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error = FT_THROW( Invalid_Argument );
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goto Exit;
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}
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FT_QNEW( ptr );
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if ( error == FT_Err_Ok )
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{
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*ptr = null_edge;
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*edge = ptr;
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}
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Exit:
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return error;
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}
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/* Frees the allocated `edge' variable. */
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static void
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sdf_edge_done( FT_Memory memory,
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SDF_Edge** edge )
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{
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if ( !memory || !edge || !*edge )
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return;
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FT_FREE( *edge );
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}
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/* Used in `FT_List_Finalize'. */
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static void
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sdf_edge_destructor( FT_Memory memory,
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void* data,
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void* user )
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{
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SDF_Edge* edge = (SDF_Edge*)data;
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sdf_edge_done( memory, &edge );
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}
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/* Creates a new `SDF_Contour' on the heap and assigns */
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/* the `contour' pointer to the newly allocated memory. */
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static FT_Error
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sdf_contour_new( FT_Memory memory,
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SDF_Contour** contour )
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{
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FT_Error error = FT_Err_Ok;
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SDF_Contour* ptr = NULL;
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if ( !memory || !contour )
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{
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error = FT_THROW( Invalid_Argument );
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goto Exit;
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}
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FT_QNEW( ptr );
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if ( error == FT_Err_Ok )
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{
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*ptr = null_contour;
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*contour = ptr;
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}
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Exit:
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return error;
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}
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/* Frees the allocated `contour' variable and also frees */
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/* the list of edges. */
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static void
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sdf_contour_done( FT_Memory memory,
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SDF_Contour** contour )
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{
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if ( !memory || !contour || !*contour )
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return;
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/* */
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FT_List_Finalize( &(*contour)->edges, sdf_edge_destructor,
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memory, NULL );
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FT_FREE( *contour );
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}
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/* Used in `FT_List_Finalize'. */
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static void
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sdf_contour_destructor( FT_Memory memory,
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void* data,
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void* user )
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{
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SDF_Contour* contour = (SDF_Contour*)data;
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sdf_contour_done( memory, &contour );
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}
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/* Creates a new `SDF_Shape' on the heap and assigns */
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/* the `shape' pointer to the newly allocated memory. */
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static FT_Error
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sdf_shape_new( FT_Memory memory,
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SDF_Shape** shape )
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{
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FT_Error error = FT_Err_Ok;
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SDF_Shape* ptr = NULL;
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if ( !memory || !shape )
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{
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error = FT_THROW( Invalid_Argument );
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goto Exit;
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}
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FT_QNEW( ptr );
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if ( error == FT_Err_Ok )
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{
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*ptr = null_shape;
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ptr->memory = memory;
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*shape = ptr;
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}
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Exit:
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return error;
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}
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/* Frees the allocated `shape' variable and also frees */
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/* the list of contours. */
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static void
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sdf_shape_done( FT_Memory memory,
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SDF_Shape** shape )
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{
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if ( !memory || !shape || !*shape )
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return;
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/* release the list of contours */
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FT_List_Finalize( &(*shape)->contours, sdf_contour_destructor,
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memory, NULL );
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/* release the allocated shape struct */
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FT_FREE( *shape );
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}
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/**************************************************************************
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*
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* shape decomposition functions
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*
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*/
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/* This function is called when walking along a new contour */
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/* so add a new contour to the shape's list. */
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static FT_Error
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sdf_move_to( const FT_26D6_Vec* to,
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void* user )
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{
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SDF_Shape* shape = ( SDF_Shape* )user;
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SDF_Contour* contour = NULL;
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FT_ListNode node = NULL;
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FT_Error error = FT_Err_Ok;
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FT_Memory memory = shape->memory;
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if ( !to || !user )
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{
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error = FT_THROW( Invalid_Argument );
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goto Exit;
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}
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error = sdf_contour_new( memory, &contour );
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if ( error != FT_Err_Ok )
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goto Exit;
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FT_QNEW( node );
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if ( error != FT_Err_Ok )
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goto Exit;
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contour->last_pos = *to;
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node->data = contour;
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FT_List_Add( &shape->contours, node );
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Exit:
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return error;
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}
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static FT_Error
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sdf_line_to( const FT_26D6_Vec* to,
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void* user )
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{
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SDF_Shape* shape = ( SDF_Shape* )user;
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SDF_Edge* edge = NULL;
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SDF_Contour* contour = NULL;
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FT_ListNode node = NULL;
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FT_Error error = FT_Err_Ok;
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FT_Memory memory = shape->memory;
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if ( !to || !user )
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{
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error = FT_THROW( Invalid_Argument );
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goto Exit;
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}
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contour = ( SDF_Contour* )shape->contours.tail->data;
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if ( contour->last_pos.x == to->x &&
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contour->last_pos.y == to->y )
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goto Exit;
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error = sdf_edge_new( memory, &edge );
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if ( error != FT_Err_Ok )
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goto Exit;
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FT_QNEW( node );
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if ( error != FT_Err_Ok )
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goto Exit;
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edge->edge_type = SDF_EDGE_LINE;
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edge->start_pos = contour->last_pos;
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edge->end_pos = *to;
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contour->last_pos = *to;
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node->data = edge;
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FT_List_Add( &contour->edges, node );
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Exit:
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return error;
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}
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static FT_Error
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sdf_conic_to( const FT_26D6_Vec* control_1,
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const FT_26D6_Vec* to,
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void* user )
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{
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SDF_Shape* shape = ( SDF_Shape* )user;
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SDF_Edge* edge = NULL;
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SDF_Contour* contour = NULL;
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FT_ListNode node = NULL;
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FT_Error error = FT_Err_Ok;
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FT_Memory memory = shape->memory;
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if ( !control_1 || !to || !user )
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{
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error = FT_THROW( Invalid_Argument );
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goto Exit;
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}
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contour = ( SDF_Contour* )shape->contours.tail->data;
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error = sdf_edge_new( memory, &edge );
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if ( error != FT_Err_Ok )
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goto Exit;
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FT_QNEW( node );
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if ( error != FT_Err_Ok )
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goto Exit;
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edge->edge_type = SDF_EDGE_CONIC;
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edge->start_pos = contour->last_pos;
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edge->control_a = *control_1;
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edge->end_pos = *to;
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contour->last_pos = *to;
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node->data = edge;
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FT_List_Add( &contour->edges, node );
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Exit:
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return error;
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}
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static FT_Error
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sdf_cubic_to( const FT_26D6_Vec* control_1,
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const FT_26D6_Vec* control_2,
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const FT_26D6_Vec* to,
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void* user )
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{
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SDF_Shape* shape = ( SDF_Shape* )user;
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SDF_Edge* edge = NULL;
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SDF_Contour* contour = NULL;
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FT_ListNode node = NULL;
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FT_Error error = FT_Err_Ok;
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FT_Memory memory = shape->memory;
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if ( !control_2 || !control_1 || !to || !user )
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{
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error = FT_THROW( Invalid_Argument );
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goto Exit;
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}
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contour = ( SDF_Contour* )shape->contours.tail->data;
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error = sdf_edge_new( memory, &edge );
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if ( error != FT_Err_Ok )
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goto Exit;
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FT_QNEW( node );
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if ( error != FT_Err_Ok )
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goto Exit;
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edge->edge_type = SDF_EDGE_CUBIC;
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edge->start_pos = contour->last_pos;
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edge->control_a = *control_1;
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edge->control_b = *control_2;
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edge->end_pos = *to;
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contour->last_pos = *to;
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node->data = edge;
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FT_List_Add( &contour->edges, node );
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Exit:
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return error;
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}
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FT_DEFINE_OUTLINE_FUNCS(
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sdf_decompose_funcs,
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(FT_Outline_MoveTo_Func) sdf_move_to, /* move_to */
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(FT_Outline_LineTo_Func) sdf_line_to, /* line_to */
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(FT_Outline_ConicTo_Func) sdf_conic_to, /* conic_to */
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(FT_Outline_CubicTo_Func) sdf_cubic_to, /* cubic_to */
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0, /* shift */
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0 /* delta */
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)
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/* function decomposes the outline and puts it into the `shape' struct */
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static FT_Error
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sdf_outline_decompose( FT_Outline* outline,
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SDF_Shape* shape )
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{
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FT_Error error = FT_Err_Ok;
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if ( !outline || !shape )
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{
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error = FT_THROW( Invalid_Argument );
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goto Exit;
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}
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error = FT_Outline_Decompose( outline, &sdf_decompose_funcs, (void*)shape );
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Exit:
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return error;
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}
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/**************************************************************************
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*
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* for debugging
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*
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*/
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#ifdef FT_DEBUG_LEVEL_TRACE
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static void
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sdf_shape_dump( SDF_Shape* shape )
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{
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FT_UInt num_contours = 0;
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FT_UInt total_edges = 0;
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FT_ListRec contour_list;
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if ( !shape )
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{
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FT_TRACE5(( "[sdf] sdf_shape_dump: null shape\n" ));
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return;
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}
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contour_list = shape->contours;
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FT_TRACE5(( "-------------------------------------------------\n" ));
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FT_TRACE5(( "[sdf] sdf_shape_dump:\n" ));
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while ( contour_list.head != NULL )
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{
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FT_UInt num_edges = 0;
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FT_ListRec edge_list;
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SDF_Contour* contour = (SDF_Contour*)contour_list.head->data;
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edge_list = contour->edges;
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FT_TRACE5(( "Contour %d\n", num_contours ));
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while ( edge_list.head != NULL )
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{
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SDF_Edge* edge = (SDF_Edge*)edge_list.head->data;
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FT_TRACE5(( " Edge %d\n", num_edges ));
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switch (edge->edge_type) {
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case SDF_EDGE_LINE:
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FT_TRACE5(( " Edge Type: Line\n" ));
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FT_TRACE5(( " ---------------\n" ));
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FT_TRACE5(( " Start Pos: %d, %d\n", edge->start_pos.x,
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edge->start_pos.y ));
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FT_TRACE5(( " End Pos : %d, %d\n", edge->end_pos.x,
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edge->end_pos.y ));
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break;
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case SDF_EDGE_CONIC:
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FT_TRACE5(( " Edge Type: Conic Bezier\n" ));
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FT_TRACE5(( " -----------------------\n" ));
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FT_TRACE5(( " Start Pos: %d, %d\n", edge->start_pos.x,
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edge->start_pos.y ));
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FT_TRACE5(( " Ctrl1 Pos: %d, %d\n", edge->control_a.x,
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edge->control_a.y ));
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FT_TRACE5(( " End Pos : %d, %d\n", edge->end_pos.x,
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edge->end_pos.y ));
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break;
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case SDF_EDGE_CUBIC:
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FT_TRACE5(( " Edge Type: Cubic Bezier\n" ));
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FT_TRACE5(( " -----------------------\n" ));
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FT_TRACE5(( " Start Pos: %d, %d\n", edge->start_pos.x,
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edge->start_pos.y ));
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FT_TRACE5(( " Ctrl1 Pos: %d, %d\n", edge->control_a.x,
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edge->control_a.y ));
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FT_TRACE5(( " Ctrl2 Pos: %d, %d\n", edge->control_b.x,
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edge->control_b.y ));
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FT_TRACE5(( " End Pos : %d, %d\n", edge->end_pos.x,
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edge->end_pos.y ));
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break;
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default:
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break;
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}
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num_edges++;
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total_edges++;
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edge_list.head = edge_list.head->next;
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}
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num_contours++;
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contour_list.head = contour_list.head->next;
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}
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FT_TRACE5(( "\n" ));
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FT_TRACE5(( "*note: the above values are in 26.6 fixed point format*\n" ));
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FT_TRACE5(( "total number of contours = %d\n", num_contours ));
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FT_TRACE5(( "total number of edges = %d\n", total_edges ));
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FT_TRACE5(( "[sdf] sdf_shape_dump complete\n" ));
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FT_TRACE5(( "-------------------------------------------------\n" ));
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}
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#endif
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/**************************************************************************
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*
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* interface functions
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*
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*/
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static FT_Error
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sdf_raster_new( FT_Memory memory,
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FT_Raster* araster)
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{
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FT_Error error = FT_Err_Ok;
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SDF_TRaster* raster = NULL;
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*araster = 0;
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if ( !FT_ALLOC( raster, sizeof( SDF_TRaster ) ) )
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{
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raster->memory = memory;
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*araster = (FT_Raster)raster;
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}
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return error;
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}
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static void
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sdf_raster_reset( FT_Raster raster,
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unsigned char* pool_base,
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unsigned long pool_size )
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{
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/* no use of this function */
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FT_UNUSED( raster );
|
|
FT_UNUSED( pool_base );
|
|
FT_UNUSED( pool_size );
|
|
}
|
|
|
|
static FT_Error
|
|
sdf_raster_set_mode( FT_Raster raster,
|
|
unsigned long mode,
|
|
void* args )
|
|
{
|
|
FT_UNUSED( raster );
|
|
FT_UNUSED( mode );
|
|
FT_UNUSED( args );
|
|
|
|
|
|
return FT_Err_Ok;
|
|
}
|
|
|
|
static FT_Error
|
|
sdf_raster_render( FT_Raster raster,
|
|
const FT_Raster_Params* params )
|
|
{
|
|
FT_Error error = FT_Err_Ok;
|
|
SDF_TRaster* sdf_raster = (SDF_TRaster*)raster;
|
|
FT_Outline* outline = NULL;
|
|
const SDF_Raster_Params* sdf_params = (const SDF_Raster_Params*)params;
|
|
|
|
|
|
/* check for valid arguments */
|
|
if ( !sdf_raster || !sdf_params )
|
|
{
|
|
error = FT_THROW( Invalid_Argument );
|
|
goto Exit;
|
|
}
|
|
|
|
outline = (FT_Outline*)sdf_params->root.source;
|
|
|
|
/* check if the outline is valid or not */
|
|
if ( !outline )
|
|
{
|
|
error = FT_THROW( Invalid_Outline );
|
|
goto Exit;
|
|
}
|
|
|
|
/* if the outline is empty, return */
|
|
if ( outline->n_points <= 0 || outline->n_contours <= 0 )
|
|
goto Exit;
|
|
|
|
/* check if the outline has valid fields */
|
|
if ( !outline->contours || !outline->points )
|
|
{
|
|
error = FT_THROW( Invalid_Outline );
|
|
goto Exit;
|
|
}
|
|
|
|
/* check if spread is set properly */
|
|
if ( sdf_params->spread > MAX_SPREAD ||
|
|
sdf_params->spread < MIN_SPREAD )
|
|
{
|
|
FT_TRACE0((
|
|
"[sdf] sdf_raster_render:\n"
|
|
" The `spread' field of `SDF_Raster_Params' is invalid,\n"
|
|
" the value of this field must be within [%d, %d].\n"
|
|
" Also, you must pass `SDF_Raster_Params' instead of the\n"
|
|
" default `FT_Raster_Params' while calling this function\n"
|
|
" and set the fields properly.\n"
|
|
, MIN_SPREAD, MAX_SPREAD) );
|
|
error = FT_THROW( Invalid_Argument );
|
|
goto Exit;
|
|
}
|
|
|
|
/* temporary */
|
|
|
|
FT_Memory memory = sdf_raster->memory;
|
|
|
|
SDF_Shape * shape = NULL;
|
|
sdf_shape_new( memory, &shape );
|
|
|
|
sdf_outline_decompose( outline, shape );
|
|
|
|
sdf_shape_dump( shape );
|
|
|
|
sdf_shape_done( memory, &shape );
|
|
|
|
/* --------- */
|
|
|
|
Exit:
|
|
error = FT_THROW( Unimplemented_Feature );
|
|
return error;
|
|
}
|
|
|
|
static void
|
|
sdf_raster_done( FT_Raster raster )
|
|
{
|
|
FT_Memory memory = (FT_Memory)((SDF_TRaster*)raster)->memory;
|
|
|
|
|
|
FT_FREE( raster );
|
|
}
|
|
|
|
FT_DEFINE_RASTER_FUNCS(
|
|
ft_sdf_raster,
|
|
|
|
FT_GLYPH_FORMAT_OUTLINE,
|
|
|
|
(FT_Raster_New_Func) sdf_raster_new, /* raster_new */
|
|
(FT_Raster_Reset_Func) sdf_raster_reset, /* raster_reset */
|
|
(FT_Raster_Set_Mode_Func) sdf_raster_set_mode, /* raster_set_mode */
|
|
(FT_Raster_Render_Func) sdf_raster_render, /* raster_render */
|
|
(FT_Raster_Done_Func) sdf_raster_done /* raster_done */
|
|
)
|
|
|
|
/* END */
|