preliminary release of the EMF import text reassembly feature.

(based on libTERE (TExt REassembly), not yet published)

libTERE examines all the text in an EMF file, which consists only of 
little chunks in different formats, and attempts to reassemble it into 
an editable SVG text object, with color, different fonts and so forth.
(only tested with English)

(bzr r11668.1.45)

1 files changed, 248 insertions, 0 deletions

diff --git a/src/extension/internal/text_reassemble.h b/src/extension/internal/text_reassemble.h
new file mode 100644
index 000000000..04c63940f
--- /dev/null
+++ b/src/extension/internal/text_reassemble.h
@@ -0,0 +1,248 @@
+/*  text_reassemble.h
+version 0.0.2 2012-12-07
+Copyright 2012, Caltech and David Mathog
+
+See text_reassemble.c for notes
+
+*/
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <math.h>
+#include <stdint.h>
+#include <ctype.h>
+#include <fontconfig/fontconfig.h>
+#include <ft2build.h>
+#include <iconv.h>
+#include FT_FREETYPE_H
+#include FT_GLYPH_H
+
+#define TEREMIN(A,B) (A < B ? A : B)
+#define TEREMAX(A,B) (A > B ? A : B)
+
+#ifndef M_PI
+# define M_PI		3.14159265358979323846	/* pi */
+#endif 
+#define ALLOCINFO_CHUNK 32
+#define ALLOCOUT_CHUNK  8192
+#define TRPRINT trinfo_append_out
+
+/* text alignment types */
+#define ALILEFT    0x01
+#define ALICENTER  0x02
+#define ALIRIGHT   0x04
+#define ALIHORI    0x07
+#define ALITOP     0x08
+#define ALIBASE    0x10
+#define ALIBOT     0x20
+#define ALIVERT    0x38
+
+/* language direction types */
+#define LDIR_LR    0x00
+#define LDIR_RL    0x01
+#define LDIR_TB    0x02
+
+/* Flags */
+#define TR_EMFBOT  0x01 /* use an approximation compatible with EMF file's "BOTTOM" text orientation, which is not the "bottom" for Freetype fonts  */
+
+/* complex classification types
+   TR_TEXT    simple text object
+   TR_LINE    linear assembly of TR_TEXTS
+   TR_PARA_UJ sequential assembly of TR_LINE into a paragraph, with unknown justification properties
+   TR_PARA_LJ ..., left justified
+   TR_PARA_CJ ..., center justified
+   TR_PARA_RJ ..., right justified
+*/
+enum tr_classes {TR_TEXT,TR_LINE,TR_PARA_UJ,TR_PARA_LJ,TR_PARA_CJ,TR_PARA_RJ};
+
+/* Fontinfo structure, values related to fonts */
+typedef struct {
+   FT_Face     face;        /* font face structures (FT_FACE is a pointer!)                         */
+   uint8_t    *file;        /* pointers to font paths to files                                      */
+   uint8_t    *fname;       /* pointers to font names                                               */
+   FcPattern  *fpat;        /* must hang onto this or faces operations break                        */
+   double      spcadv;      /* advance equal to a space, in points                                  */
+   double      fsize;       /* face size in points                                                  */
+} FNT_SPECS;
+
+typedef struct {
+   FT_Library  library;     /* Fontconfig handle                                                    */
+   FNT_SPECS  *fonts;       /* Array of fontinfo structures                                         */
+   int         space;       /* storage slots allocated                                              */
+   int         used;        /* storage slots in use                                                 */
+} FT_INFO;
+
+typedef struct {
+   uint8_t    *string;      /* UTF-8 text                                                           */
+   double      ori;         /* Orientation, angle of characters with respect to baseline in degrees */
+   double      fs;          /* font size of text                                                    */
+   double      x;           /* x coord relative to tri x,y, in points                               */
+   double      y;           /* y coord                                                              */
+   double      boff;        /* Y LL corner - boff finds baseline                                    */
+   double      vadvance;    /* Line spacing typically 1.25 or 1.2,  only set on the first text
+                                 element in a complex                                               */
+   uint32_t    color;       /* RGBA                                                                 */
+   int         taln;        /* text alignment with respect to x,y                                   */
+   int         ldir;        /* language diretion LDIR_*                                             */
+   int         italics;     /* italics, as in FontConfig                                            */
+   int         weight;      /* weight, as in FontConfig                                             */
+   int         condensed;   /* condensed, as in FontConfig                                          */
+   int         co;          /* condensed override, if set Font name included narrow                 */
+   int         rt_tidx;     /* index of rectangle that contains it                                  */
+   int         fi_idx;      /* index of the font it uses                                            */
+} TCHUNK_SPECS;
+
+/* Text Info/Position Info structure, values related to text properties and string geometry
+   Coordinates here are INTERNAL, after offset/rotate using values in TR_INFO.
+*/
+typedef struct {
+   TCHUNK_SPECS *chunks;     /* text chunks                                                         */
+   int         space;        /* storage slots allocated                                             */
+   int         used;         /* storage slots in use                                                */
+} TP_INFO;
+
+/* Bounding Rectangle(s) structure
+   Coordinates here are INTERNAL, after offset/rotate using values in TR_INFO.
+*/
+typedef struct {
+   double      xll;           /* x rectangle lower left corner                                      */
+   double      yll;           /* y "                                                                */
+   double      xur;           /* x upper right corner                                               */
+   double      yur;           /* y "                                                                */
+   double      xbearing;      /* x bearing of the leftmost character                                */
+} BRECT_SPECS;
+
+typedef struct {
+   BRECT_SPECS *rects;         /* bounding rectangles                                               */
+   int         space;          /* storage slots allocated                                           */
+   int         used;           /* storage slots in use                                              */
+} BR_INFO;
+
+typedef struct {
+   int        *members;        /* array of immediate children (for TR_PARA_* these are indicies 
+                                   for TR_TEXT or TR_LINE complexes also in cxi. For TR_TEXT
+                                   and TR_LINE these are indices to the actual text in tpi.)        */
+   int         space;          /* storage slots allocated                                           */
+   int         used;           /* storage slots in use                                              */
+} CHILD_SPECS;
+
+/* Complex info structure, values related to the assembly of complex text from smaller pieces */
+typedef struct {
+   int               rt_cidx;  /* index of rectangle that contains all members                      */
+   enum tr_classes   type;     /* classification of the complex                                     */
+   CHILD_SPECS       kids;     /* immediate child nodes of this complex, for type TR_TEXT the
+                                  idx refers to the tpi data. otherwise, cxi data                   */
+} CX_SPECS;
+
+typedef struct {
+   CX_SPECS   *cx;             /* complexes                                                         */
+   int         space;          /* storage slots allocated                                           */
+   int         used;           /* storage slots in use                                              */
+   int         phase1;         /* Number of complexes (lines + text fragments) entered in phase 1   */
+   int         lines;          /* Number of lines in phase 1                                        */
+   int         paras;          /* Number of complexes (paras) entered in phase 2                    */
+} CX_INFO;
+
+/* Text reassemble, overall structure */
+typedef struct {
+   FT_INFO    *fti;            /* Font info storage                                                 */
+   TP_INFO    *tpi;            /* Text Info/Position Info storage                                   */
+   BR_INFO    *bri;            /* Bounding Rectangle Info storage                                   */
+   CX_INFO    *cxi;            /* Complex Info storage                                              */
+   uint8_t    *out;            /* buffer to hold formatted output                                   */
+   double      qe;             /* quantization error in points.                                     */
+   double      esc;            /* escapement angle in DEGREES                                       */
+   double      x;              /* coordinates of first text, in points                              */
+   double      y;
+   int         dirty;          /* 1 if text records are loaded                                      */ 
+   int         use_kern;       /* 1 if kerning is used, 0 if not                                    */
+   int         load_flags;     /* FT_LOAD_NO_SCALE or FT_LOAD_TARGET_NORMAL                         */
+   int         kern_mode;      /* FT_KERNING_DEFAULT, FT_KERNING_UNFITTED, or FT_KERNING_UNSCALED   */
+   int         outspace;       /* storage in output buffer  allocated                               */
+   int         outused;        /* storage in output buffer in use                                   */
+} TR_INFO;
+
+/* padding added to rectangles before overlap test */
+typedef struct {
+   double up;                  /* to top                                                            */
+   double down;                /* to bottom                                                         */
+   double left;                /* to left                                                           */
+   double right;               /* to right                                                          */
+} RT_PAD;
+
+/* iconv() has a funny cast on some older systems, on most recent ones
+   it is just char **.  This tries to work around the issue.  If you build this
+   on another funky system this code may need to be modified, or define ICONV_CAST
+   on the compile line(but it may be tricky).
+*/
+#ifdef SOL8
+#define ICONV_CAST (const char **)
+#endif  //SOL8
+#if !defined(ICONV_CAST)
+#define ICONV_CAST (char **)
+#endif  //ICONV_CAST
+
+/* Prototypes */
+int           TR_findcasesub(char *string, char *sub);
+int           TR_getadvance(FNT_SPECS *fsp, uint32_t wc, uint32_t pc, int load_flags, int kern_mode, int *ymin, int *ymax);
+int           TR_getkern2(FNT_SPECS *fsp, uint32_t wc, uint32_t pc, int kern_mode);
+int           TR_kern_gap(FNT_SPECS *fsp, TCHUNK_SPECS *tsp, TCHUNK_SPECS *ptsp, int kern_mode);
+void          TR_rt_pad_set(RT_PAD *rt_pad, double up, double down, double left, double right);
+double        TR_baseline(TR_INFO *tri, int src, double *AscMax, double *DscMax);
+int           TR_check_set_vadvance(TR_INFO *tri, int src, int lines);
+int           TR_layout_analyze(TR_INFO *tri);
+void          TR_layout_2_svg(TR_INFO *tri);
+int           TR_weight_FC_to_SVG(int weight);
+
+FT_INFO      *ftinfo_init(void);
+int           ftinfo_make_insertable(FT_INFO *fti);
+int           ftinfo_insert(FT_INFO *fti, FNT_SPECS *fsp);
+FT_INFO      *ftinfo_release(FT_INFO *fti);
+FT_INFO      *ftinfo_clear(FT_INFO *fti);
+
+int           csp_make_insertable(CHILD_SPECS *csp);
+int           csp_insert(CHILD_SPECS *csp, int src);
+int           csp_merge(CHILD_SPECS *dst, CHILD_SPECS *src);
+void          csp_release(CHILD_SPECS *csp);
+#define       csp_clear csp_release  /* since the CHILD_SPECS area itself is not deleted, clear == reset */
+
+CX_INFO      *cxinfo_init(void);
+int           cxinfo_make_insertable(CX_INFO *cxi);
+int           cxinfo_insert(CX_INFO *cxi, int src, int src_rt_idx, enum tr_classes type);
+int           cxinfo_append(CX_INFO *cxi, int src, enum tr_classes type);
+int           cxinfo_merge(CX_INFO *cxi,  int dst, int src, enum tr_classes type);
+CX_INFO      *cxinfo_release(CX_INFO *cxi);
+void          cxinfo_dump(TR_INFO *tri);
+
+TP_INFO      *tpinfo_init(void);
+int           tpinfo_make_insertable(TP_INFO *tpi);
+int           tpinfo_insert(TP_INFO *tpi, TCHUNK_SPECS *tsp);
+TP_INFO      *tpinfo_release(TP_INFO *tpi);
+
+BR_INFO      *brinfo_init(void);
+int           brinfo_make_insertable(BR_INFO *bri);
+int           brinfo_insert(BR_INFO *bri, BRECT_SPECS *element);
+int           brinfo_merge(BR_INFO *bri, int dst, int src);
+enum tr_classes 
+              brinfo_pp_alignment(BR_INFO *bri, int dst, int src, double slop, enum tr_classes type);
+int           brinfo_overlap(BR_INFO *bri, int dst, int src, RT_PAD *rp_dst, RT_PAD *rp_src);
+BR_INFO      *brinfo_release(BR_INFO *bri);
+
+TR_INFO      *trinfo_init(TR_INFO *tri);
+TR_INFO      *trinfo_release(TR_INFO *tri);
+TR_INFO      *trinfo_release_except_FC(TR_INFO *tri);
+TR_INFO      *trinfo_clear(TR_INFO *tri);
+int           trinfo_load_fontname(TR_INFO *tri, uint8_t *fontname, TCHUNK_SPECS *tsp);
+int           trinfo_load_qe(TR_INFO *tri, double qe);
+int           trinfo_load_ft_opts(TR_INFO *tri, int use_kern, int load_flags, int kern_mode);
+int           trinfo_load_textrec(TR_INFO *tri, TCHUNK_SPECS *tsp, double escapement, int flags);  
+int           trinfo_append_out(TR_INFO *tri, char *src);
+
+#ifdef __cplusplus
+}
+#endif