Added a new version of the "smooth". This one uses

an algorithm that is very close to our standard raster.

However, it is (theorically for now) capable of direct
composition !!

demos/src/ftgrays2.h

@@ -0,0 +1,102 @@
+#ifndef FTGRAYS2_H
+#define FTGRAYS2_H
+
+typedef int   TScan;
+typedef long  TPos;
+typedef float TDist;
+
+#define FT_MAX_GRAY_SPANS  32
+
+typedef struct FT_GraySpan_
+{
+  short          x;
+  short          len;
+  unsigned char  coverage;
+
+} FT_GraySpan;
+
+typedef int (*FT_GraySpan_Func)( int           y,
+                                 int           count,
+                                 FT_GraySpan*  spans,
+                                 void*         user );
+                                        
+typedef enum {
+
+  dir_up    = 0,
+  dir_down  = 1,
+  dir_right = 2,
+  dir_left  = 3,
+
+  dir_horizontal = 2,
+  dir_reverse    = 1,
+  
+  dir_unknown = 4
+  
+} TDir;
+
+typedef struct TCell_
+{
+  unsigned short  x;
+  unsigned short  y;
+  unsigned short  pos;
+  TDir            dir;
+
+} TCell, *PCell;
+
+
+
+typedef struct TRaster_
+{
+  PCell   cells;
+  PCell   cursor;
+  PCell   cell_limit;
+  int     max_cells;
+  int     num_cells;
+
+  TScan   min_ex, max_ex;
+  TScan   min_ey, max_ey;
+  TPos    min_x,  min_y;
+  TPos    max_x,  max_y;
+
+  TScan   ex, ey;
+  TScan   cx, cy;
+  TPos    x,  y;
+
+  PCell   contour_cell;  /* first contour cell */
+
+  char    joint;
+  char    horizontal;
+  TDir    dir;
+  PCell   last;
+  
+  FT_Vector  starter;
+  FT_Vector* start;
+
+  int     error;
+
+  FT_Vector   bez_stack[32*3];
+  int         lev_stack[32];
+
+  FT_Outline  outline;
+  FT_Bitmap   target;
+
+  FT_GraySpan gray_spans[ FT_MAX_GRAY_SPANS ];
+  int         num_gray_spans;
+
+  FT_GraySpan_Func  render_span;
+  void*             render_span_closure;
+  int               span_y;
+
+} TRaster, *PRaster;
+
+  extern
+  int  grays2_raster_render( TRaster*     raster,
+                             FT_Outline*  outline,
+                             FT_Bitmap*   target_map );
+
+  extern
+  int  grays2_raster_init( FT_Raster    raster,
+                           const char*  pool_base,
+                           long         pool_size );
+
+#endif