[sdf] Add raster parameters structure.

* src/sdf/ftsdf.h (SDF_Raster_Params): New structure.

* src/sdf/sdf.c: Include source files in order to make a single
object of the module.

ChangeLog

@@ -1,3 +1,12 @@
+2020-08-17  Anuj Verma  <anujv@iitbhilai.ac.in>
+
+	[sdf] Add raster parameters structure.
+
+	* src/sdf/ftsdf.h (SDF_Raster_Params): New structure.
+
+	* src/sdf/sdf.c: Include source files in order to make a single
+	object of the module.
+
 2020-08-17  Anuj Verma  <anujv@iitbhilai.ac.in>
 
 	[sdf] Add 'sdf' renderer.

src/sdf/ftsdf.h

@@ -2,6 +2,68 @@
 #ifndef FTSDF_H_
 #define FTSDF_H_
 
+#include <ft2build.h>
+#include FT_CONFIG_CONFIG_H
+#include <freetype/ftimage.h>
+
+/* common properties and function */
+#include "ftsdfcommon.h"
+
+FT_BEGIN_HEADER
+
+  /**************************************************************************
+   *
+   * @struct:
+   *   SDF_Raster_Params
+   *
+   * @description:
+   *   This struct must be passed to the raster render function
+   *   @FT_Raster_RenderFunc instead of @FT_Raster_Params because the
+   *   rasterizer requires some additional information to render properly. 
+   *
+   * @fields:
+   *   root ::
+   *     The native raster parameters structure.
+   *
+   *   spread ::
+   *     This is an essential parameter/property required by the renderer. 
+   *     `spread` defines the maximum unsigned value that is present in the
+   *     final SDF output.  For the default value check file
+   *     `ftsdfcommon.h`.
+   *
+   *   flip_sign ::
+   *     By default positive values indicate positions inside of contours,
+   *     i.e., filled by a contour.  If this property is true then that
+   *     output will be the opposite of the default, i.e., negative values
+   *     indicate positions inside of contours.
+   *
+   *   flip_y ::
+   *     Setting this parameter to true maked the output image flipped
+   *     along the y-axis.
+   *
+   *   overlaps ::
+   *     Set this to true to generate SDF for glyphs having overlapping
+   *     contours.  The overlapping support is limited to glyphs that do not
+   *     have self-intersecting contours.  Also, removing overlaps require a
+   *     considerable amount of extra memory; additionally, it will not work
+   *     if generating SDF from bitmap.
+   *
+   * @note:
+   *   All properties are valid for both the 'sdf' and 'bsdf' renderers; the
+   *   exception is `overlaps`, which gets ignored by the 'bsdf' renderer.
+   *
+   */
+  typedef struct  SDF_Raster_Params_
+  {
+    FT_Raster_Params  root;
+    FT_UInt           spread;
+    FT_Bool           flip_sign;
+    FT_Bool           flip_y;
+    FT_Bool           overlaps;
+
+  } SDF_Raster_Params;
+
+FT_END_HEADER
 
 #endif /* FTSDF_H_ */
 

src/sdf/ftsdfrend.h

@@ -50,6 +50,7 @@ FT_BEGIN_HEADER
    * @note:
    *   All properties except `overlaps` are valid for both the 'sdf' and
    *   'bsdf' renderers.
+   *
    */
   typedef struct  SDF_Renderer_Module_
   {

src/sdf/sdf.c

@@ -1,3 +1,8 @@
 
+#define FT_MAKE_OPTION_SINGLE_OBJECT
+
+#include "ftsdfrend.c"
+#include "ftbsdf.c"
+#include "ftsdf.c"
 
 /* END */