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[sdf -> bsdf renderer] Convert 8bit bitmap to 16bit. 

* src/sdf/ftbsdf.c (bsdf_copy_source_to_target): Added
  extra parameter to flip the bitmap vertically.

* src/sdf/ftbsdf.c (bsdf_copy_source_to_target):
  Implemented functionality to convert 8bits per
  pixel bitmap to a 16bits per pixel bitmap, which
  will be used to generate SDF.
This commit is contained in:
Anuj Verma 2020-07-25 09:00:47 +05:30 committed by anujverma
parent 2c77a8acb2
commit 99a4759290
2 changed files with 89 additions and 6 deletions
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12
[GSoC]ChangeLog
View File

@ -1,3 +1,15 @@
2020-07-25 Anuj Verma <anujv@iitbhilai.ac.in>
[sdf -> bsdf renderer] Convert 8bit bitmap to 16bit.
* src/sdf/ftbsdf.c (bsdf_copy_source_to_target): Added
extra parameter to flip the bitmap vertically.
* src/sdf/ftbsdf.c (bsdf_copy_source_to_target):
Implemented functionality to convert 8bits per
pixel bitmap to a 16bits per pixel bitmap, which
will be used to generate SDF.
2020-07-24 Anuj Verma <anujv@iitbhilai.ac.in>
[sdf] Started the `bsdf' rasterier.

83
src/sdf/ftbsdf.c
View File

@ -20,22 +20,36 @@
goto Exit; \
} while ( 0 )
/**************************************************************************
*
* typedefs
*
*/
typedef FT_Short FT_6D10; /* 6.10 fixed point representation */
/**************************************************************************
*
* rasterizer functions
*
*/
/* This function copy the `source' bitmap on top of */
/* `target' bitmap's center. It also converts the */
/* values to 16bpp in a fixed point format. */
static FT_Error
bsdf_copy_source_to_target( const FT_Bitmap* source,
FT_Bitmap* target )
FT_Bitmap* target,
FT_Bool flip_y )
{
FT_Error error = FT_Err_Ok;
FT_Bool is_monochrome = 0;
FT_Int x_diff, y_diff;
FT_Int num_channels;
FT_Byte* t, s;
FT_Int t_i, t_j, s_i, s_j;
FT_Byte* s;
FT_6D10* t;
/* again check the parameters (probably unnecessary) */
if ( !source || !target )
@ -92,7 +106,7 @@
x_diff /= 2;
y_diff /= 2;
t = target->buffer;
t = (FT_6D10*)target->buffer;
s = source->buffer;
/* For now we only support pixel mode `FT_PIXEL_MODE_MONO' */
@ -102,14 +116,70 @@
/* since the target bitmap can be 16bpp we manually */
/* convert the source bitmap to desired bpp. */
switch ( source->pixel_mode ) {
case FT_PIXEL_MODE_GRAY2:
case FT_PIXEL_MODE_GRAY4:
case FT_PIXEL_MODE_GRAY16:
case FT_PIXEL_MODE_LCD:
case FT_PIXEL_MODE_LCD_V:
case FT_PIXEL_MODE_MONO:
/* [TODO] */
FT_ERROR(( "[bsdf] bsdf_copy_source_to_target: "
"support for pixel mode not yet added\n" ));
error = FT_THROW( Unimplemented_Feature );
break;
case FT_PIXEL_MODE_GRAY:
/* [TODO] */
error = FT_THROW( Unimplemented_Feature );
{
FT_Int t_width = target->width;
FT_Int t_rows = target->rows;
FT_Int s_width = source->width;
FT_Int s_rows = source->rows;
/* loop through all the pixels and */
/* assign pixel values from source */
for ( t_j = 0; t_j < t_rows; t_j++ )
{
for ( t_i = 0; t_i < t_width; t_i++ )
{
FT_Int t_index = t_j * t_width + t_i;
FT_Int s_index;
FT_Short pixel_value;
s_i = t_i - x_diff;
s_j = t_j - y_diff;
/* assign 0 to the padding */
if ( s_i < 0 || s_i >= s_width ||
s_j < 0 || s_j >= s_rows )
{
t[t_index] = 0;
continue;
}
if ( flip_y )
s_index = ( s_rows - s_j - 1 ) * s_width + s_i;
else
s_index = s_j * s_width + s_i;
pixel_value = (FT_Short)s[s_index];
/* to make the fractional value 1 */
/* for completely filled pixels */
if ( pixel_value == 255 )
pixel_value = 256;
/* Assume that 256 is fractional value with */
/* 0.8 representation, to make it 6.10 left */
/* shift the value by 2. */
pixel_value <<= 2;
t[t_index] = pixel_value;
}
}
break;
}
default:
FT_ERROR(( "[bsdf] bsdf_copy_source_to_target: "
"unsopported pixel mode of source bitmap\n" ));
@ -215,7 +285,8 @@
goto Exit;
}
FT_CALL( bsdf_copy_source_to_target( source, target ) );
FT_CALL( bsdf_copy_source_to_target( source, target,
sdf_params->flip_y ) );
Exit:
return error;