diff --git a/ChangeLog b/ChangeLog index 9e855f19c..439fb89e3 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,11 @@ +2020-08-20 Anuj Verma + + [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 [sdf] Add interface functions for the 'bsdf' rasterizer. diff --git a/src/sdf/ftsdf.h b/src/sdf/ftsdf.h index 1c68aef60..a8e243dee 100644 --- a/src/sdf/ftsdf.h +++ b/src/sdf/ftsdf.h @@ -19,14 +19,14 @@ FT_BEGIN_HEADER * @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 :: * 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`. diff --git a/src/sdf/ftsdfrend.c b/src/sdf/ftsdfrend.c index 7911490b0..487010769 100644 --- a/src/sdf/ftsdfrend.c +++ b/src/sdf/ftsdfrend.c @@ -187,6 +187,14 @@ } + /*************************************************************************/ + /*************************************************************************/ + /** **/ + /** OUTLINE TO SDF CONVERTER **/ + /** **/ + /*************************************************************************/ + /*************************************************************************/ + /************************************************************************** * * interface functions @@ -421,4 +429,144 @@ (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 */