[freetype2] gsoc-anurag-2022-final a3c327aa4 2/2: [dense] Add 'dense' renderer

[Werner Lemberg]

branch: gsoc-anurag-2022-final
commit a3c327aa41feb28ffb84922804270163806258c7
Author: Anurag Thakur <anurag105csec21@bpitindia.edu.in>
Commit: Anurag Thakur <anurag105csec21@bpitindia.edu.in>

    [dense] Add 'dense' renderer
    
    * src/dense/ftdenserend.c: Add 'dense' renderer along with its interface
    functions.
    
    (ft_dense_set_mode, ft_dense_transform, ft_dense_get_cbox, ft_dense_init,
    ft_dense_done, ft_dense_render)
---
 src/dense/ftdenserend.c | 221 +++++++++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 219 insertions(+), 2 deletions(-)

diff --git a/src/dense/ftdenserend.c b/src/dense/ftdenserend.c
index a7ca8ca59..61a2b1850 100644
--- a/src/dense/ftdenserend.c
+++ b/src/dense/ftdenserend.c
@@ -1,3 +1,220 @@
-/** The 'dense' renderer */
+  /** The 'dense' renderer */
 
-/* END */
\ No newline at end of file
+#include <freetype/ftoutln.h>
+#include <freetype/internal/ftdebug.h>
+#include <freetype/internal/ftobjs.h>
+#include "ftdenserend.h"
+#include "ftdense.h"
+
+#include "ftdenseerrs.h"
+
+  /**************************************************************************
+   *
+   * The macro FT_COMPONENT is used in trace mode.  It is an implicit
+   * parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log
+   * messages during execution.
+   */
+#undef FT_COMPONENT
+#define FT_COMPONENT dense
+
+
+
+  /**************************************************************************
+   *
+   * interface functions
+   *
+   */
+
+  /* set render specific modes or attributes */
+  static FT_Error
+  ft_dense_set_mode( FT_Renderer render, FT_ULong mode_tag, FT_Pointer data )
+  {
+    /* pass it to the rasterizer */
+    return render->clazz->raster_class->raster_set_mode( render->raster, 
mode_tag,
+                                                         data );
+  }
+
+  /* transform the glyph using matrix and/or delta */
+  static FT_Error
+  ft_dense_transform( FT_Renderer      render,
+                      FT_GlyphSlot     slot,
+                      const FT_Matrix* matrix,
+                      const FT_Vector* delta )
+  {
+
+    FT_Error error = FT_Err_Ok;
+
+    if ( slot->format != render->glyph_format )
+    {
+      error = FT_THROW( Invalid_Argument );
+      goto Exit;
+    }
+
+    if ( matrix )
+      FT_Outline_Transform( &slot->outline, matrix );
+
+    if ( delta )
+      FT_Outline_Translate( &slot->outline, delta->x, delta->y );
+
+  Exit:
+    return error;
+  }
+
+  /* return the control box of a glyph's outline */
+  static void
+  ft_dense_get_cbox( FT_Renderer render, FT_GlyphSlot slot, FT_BBox* cbox )
+  {
+
+    FT_ZERO( cbox );
+
+    if ( slot->format == render->glyph_format )
+      FT_Outline_Get_CBox( &slot->outline, cbox );
+  }
+
+  static FT_Error
+  ft_dense_init( FT_Renderer render )
+  {
+    return FT_Err_Ok;
+  }
+
+  static void
+  ft_dense_done( FT_Renderer render )
+  {
+    FT_UNUSED( render );
+  }
+
+  /* generate bitmap from a glyph's slot image */
+  static FT_Error
+  ft_dense_render( FT_Renderer      render,
+                   FT_GlyphSlot     slot,
+                   FT_Render_Mode   mode,
+                   const FT_Vector* origin )
+  {
+    FT_Error    error   = FT_Err_Ok;
+    FT_Outline* outline = &slot->outline;
+    FT_Bitmap*  bitmap  = &slot->bitmap;
+
+    /* FT_FREE and FT_ALLOC_MULT macros need a variable named 'memory' */
+    FT_Memory   memory  = render->root.memory;
+
+    FT_Pos x_shift = 0;
+    FT_Pos y_shift = 0;
+
+    FT_Raster_Params params;
+
+    /* check whether slot format is correct before rendering */
+    if ( slot->format != render->glyph_format )
+    {
+      error = FT_THROW( Invalid_Glyph_Format );
+      goto Exit;
+    }
+
+    /* check mode */
+    if ( mode != FT_RENDER_MODE_NORMAL &&
+         mode != FT_RENDER_MODE_LIGHT  &&
+         mode != FT_RENDER_MODE_LCD    &&
+         mode != FT_RENDER_MODE_LCD_V  )
+    {
+      error = FT_THROW( Cannot_Render_Glyph );
+      goto Exit;
+    }
+
+
+    /* deallocate the previously allocated bitmap */
+    if ( slot->internal->flags & FT_GLYPH_OWN_BITMAP )
+    {
+      FT_FREE( bitmap->buffer );
+      slot->internal->flags &= ~FT_GLYPH_OWN_BITMAP;
+    }
+
+    /* preset the bitmap using the glyph's outline */
+    if ( ft_glyphslot_preset_bitmap( slot, mode, origin ) )
+    {
+      error = FT_THROW( Raster_Overflow );
+      goto Exit;
+    }
+
+    if ( !bitmap->rows || !bitmap->pitch )
+      goto Exit;
+
+
+    /* allocate new one */
+    if ( FT_ALLOC_MULT( bitmap->buffer, bitmap->rows, bitmap->pitch ) )
+      goto Exit;
+
+    slot->internal->flags |= FT_GLYPH_OWN_BITMAP;
+
+    /* Calculate shift in 26.6 format */
+    x_shift = 64 * -slot->bitmap_left;
+    y_shift = 64 * -slot->bitmap_top;
+
+    if ( bitmap->pixel_mode == FT_PIXEL_MODE_LCD_V )
+       y_shift += 64 * (FT_Int)bitmap->rows / 3;
+     else
+       y_shift += 64 * (FT_Int)bitmap->rows;
+
+
+    if ( origin )
+    {
+      x_shift += origin->x;
+      y_shift += origin->y;
+    }
+
+    /* translate outline to render it into the bitmap */
+    if ( x_shift || y_shift )
+      FT_Outline_Translate( outline, x_shift, y_shift );
+
+    /* set up parameters */
+    params.target = bitmap;
+    params.source = outline;
+
+    /* render the outline */
+    error =
+        render->raster_render( render->raster, (const 
FT_Raster_Params*)&params );
+
+  Exit:
+    if ( !error )
+    {
+      /* the glyph is successfully rendered to a bitmap */
+      slot->format = FT_GLYPH_FORMAT_BITMAP;
+    }
+    else if ( slot->internal->flags & FT_GLYPH_OWN_BITMAP )
+    {
+      FT_FREE( bitmap->buffer );
+      slot->internal->flags &= ~FT_GLYPH_OWN_BITMAP;
+    }
+
+    if ( x_shift || y_shift )
+      FT_Outline_Translate( outline, -x_shift, -y_shift );
+
+    return error;
+  }
+
+
+  FT_DEFINE_RENDERER(
+      ft_dense_renderer_class,
+
+      FT_MODULE_RENDERER,
+      sizeof( FT_RendererRec ),
+
+      "dense",
+      0x10000L,
+      0x20000L,
+
+      NULL,
+
+      (FT_Module_Constructor)ft_dense_init,
+      (FT_Module_Destructor)ft_dense_done,
+      (FT_Module_Requester)NULL,
+
+      FT_GLYPH_FORMAT_OUTLINE,
+
+      (FT_Renderer_RenderFunc)ft_dense_render,       /* render_glyph    */
+      (FT_Renderer_TransformFunc)ft_dense_transform, /* transform_glyph */
+      (FT_Renderer_GetCBoxFunc)ft_dense_get_cbox,    /* get_glyph_cbox  */
+      (FT_Renderer_SetModeFunc)ft_dense_set_mode,    /* set_mode        */
+
+      (FT_Raster_Funcs*)&ft_dense_raster /* raster_class    */
+  )
+
+  /* END */