ref: 6cd6df55c9f23d1d01aa466e7265ec06aea062e2
parent: d27d107f157345402aefdb29d89d50446d52fded
author: Anuj Verma <anujv@iitbhilai.ac.in>
date: Thu Aug 20 17:57:43 EDT 2020
[sdf] Add 'bsdf' renderer to 'sdf' module. * src/sdf/ftsdfrend.c (ft_bsdf_render): New function. (ft_bitmap_sdf_renderer_class): New structure.
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,13 @@
2020-08-20 Anuj Verma <anujv@iitbhilai.ac.in>
+ [sdf] Add 'bsdf' renderer to 'sdf' module.
+
+ * src/sdf/ftsdfrend.c (ft_bsdf_render): New function.
+
+ (ft_bitmap_sdf_renderer_class): New structure.
+
+2020-08-20 Anuj Verma <anujv@iitbhilai.ac.in>
+
[sdf] Add interface functions for the 'bsdf' rasterizer.
* src/sdf/ftsdf.c (bsdf_raster_new, bsdf_raster_reset,
--- a/src/sdf/ftsdf.h
+++ b/src/sdf/ftsdf.h
@@ -19,7 +19,7 @@
* @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.
+ * rasterizer requires some additional information to render properly.
*
* @fields:
* root ::
@@ -26,7 +26,7 @@
* The native raster parameters structure.
*
* spread ::
- * This is an essential parameter/property required by the renderer.
+ * 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`.
--- a/src/sdf/ftsdfrend.c
+++ b/src/sdf/ftsdfrend.c
@@ -187,6 +187,14 @@
}
+ /*************************************************************************/
+ /*************************************************************************/
+ /** **/
+ /** OUTLINE TO SDF CONVERTER **/
+ /** **/
+ /*************************************************************************/
+ /*************************************************************************/
+
/**************************************************************************
*
* interface functions
@@ -419,6 +427,146 @@
(FT_Renderer_SetModeFunc) ft_sdf_set_mode, /* set_mode */
(FT_Raster_Funcs*)&ft_sdf_raster /* raster_class */
+ )
+
+
+ /*************************************************************************/
+ /*************************************************************************/
+ /** **/
+ /** BITMAP TO SDF CONVERTER **/
+ /** **/
+ /*************************************************************************/
+ /*************************************************************************/
+
+ /* generate signed distance field from glyph's bitmap */
+ static FT_Error
+ ft_bsdf_render( FT_Renderer module,
+ FT_GlyphSlot slot,
+ FT_Render_Mode mode,
+ const FT_Vector* origin )
+ {+ FT_Error error = FT_Err_Ok;
+ FT_Memory memory = NULL;
+
+ FT_Bitmap* bitmap = &slot->bitmap;
+ FT_Renderer render = NULL;
+ FT_Bitmap target;
+
+ FT_Pos x_pad = 0;
+ FT_Pos y_pad = 0;
+
+ SDF_Raster_Params params;
+ SDF_Renderer sdf_module = SDF_RENDERER( module );
+
+
+ /* initialize the bitmap in case any error occurs */
+ FT_Bitmap_Init( &target );
+
+ render = &sdf_module->root;
+ memory = render->root.memory;
+
+ /* check whether slot format is correct before rendering */
+ if ( slot->format != render->glyph_format )
+ {+ FT_ERROR(( "ft_bsdf_render: slot format must be a bitmap\n" ));
+
+ error = FT_THROW( Invalid_Glyph_Format );
+ goto Exit;
+ }
+
+ /* check whether render mode is correct */
+ if ( mode != FT_RENDER_MODE_SDF )
+ {+ FT_ERROR(( "ft_bsdf_render: need `FT_RENDER_MODE_SDF' mode\n" ));
+
+ error = FT_THROW( Cannot_Render_Glyph );
+ goto Exit;
+ }
+
+ if ( origin )
+ {+ FT_ERROR(( "ft_bsdf_render: can't translate the bitmap\n" ));
+
+ error = FT_THROW( Unimplemented_Feature );
+ goto Exit;
+ }
+
+ if ( !bitmap->rows || !bitmap->pitch )
+ goto Exit;
+
+ FT_Bitmap_New( &target );
+
+ /* padding will simply be equal to `spread` */
+ x_pad = sdf_module->spread;
+ y_pad = sdf_module->spread;
+
+ /* apply padding, which extends to all directions */
+ target.rows = bitmap->rows + y_pad * 2;
+ target.width = bitmap->width + x_pad * 2;
+
+ /* set up the target bitmap */
+ target.pixel_mode = FT_PIXEL_MODE_GRAY16;
+ target.pitch = target.width * 2;
+ target.num_grays = 65535;
+
+ if ( FT_ALLOC_MULT( target.buffer, target.rows, target.pitch ) )
+ goto Exit;
+
+ /* set up parameters */
+ params.root.target = ⌖
+ params.root.source = bitmap;
+ params.root.flags = FT_RASTER_FLAG_SDF;
+ params.spread = sdf_module->spread;
+ params.flip_sign = sdf_module->flip_sign;
+ params.flip_y = sdf_module->flip_y;
+
+ error = render->raster_render( render->raster,
+ (const FT_Raster_Params*)¶ms );
+
+ Exit:
+ if ( !error )
+ {+ /* the glyph is successfully converted to a SDF */
+ if ( slot->internal->flags & FT_GLYPH_OWN_BITMAP )
+ {+ FT_FREE( bitmap->buffer );
+ slot->internal->flags &= ~FT_GLYPH_OWN_BITMAP;
+ }
+
+ slot->bitmap = target;
+ slot->internal->flags |= FT_GLYPH_OWN_BITMAP;
+ }
+ else if ( target.buffer )
+ FT_FREE( target.buffer );
+
+ return error;
+ }
+
+
+ FT_DEFINE_RENDERER(
+ ft_bitmap_sdf_renderer_class,
+
+ FT_MODULE_RENDERER,
+ sizeof ( SDF_Renderer_Module ),
+
+ "bsdf",
+ 0x10000L,
+ 0x20000L,
+
+ NULL,
+
+ (FT_Module_Constructor)ft_sdf_init,
+ (FT_Module_Destructor) ft_sdf_done,
+ (FT_Module_Requester) ft_sdf_requester,
+
+ FT_GLYPH_FORMAT_BITMAP,
+
+ (FT_Renderer_RenderFunc) ft_bsdf_render, /* render_glyph */
+ (FT_Renderer_TransformFunc)ft_sdf_transform, /* transform_glyph */
+ (FT_Renderer_GetCBoxFunc) ft_sdf_get_cbox, /* get_glyph_cbox */
+ (FT_Renderer_SetModeFunc) ft_sdf_set_mode, /* set_mode */
+
+ (FT_Raster_Funcs*)&ft_bitmap_sdf_raster /* raster_class */
)
/* END */