[sdf] Partially completed the coarse grid optimization.

* src/sdf/ftsdf.c (sdf_generate_coarse_grid): Added
  functionality to check distances of all edges from
  the coarse grid and add the relevant edges to the 
  list.
  [Note]: The function is not complete yet.
This commit is contained in:
Anuj Verma 2020-07-10 16:44:14 +05:30 committed by anujverma
parent 111b755128
commit 992609a1db
2 changed files with 136 additions and 11 deletions

View File

@ -1,3 +1,13 @@
2020-07-10 Anuj Verma <anujv@iitbhilai.ac.in>
[sdf] Partially completed the coarse grid optimization.
* src/sdf/ftsdf.c (sdf_generate_coarse_grid): Added
functionality to check distances of all edges from
the coarse grid and add the relevant edges to the
list.
[Note]: The function is not complete yet.
2020-07-10 Anuj Verma <anujv@iitbhilai.ac.in>
[sdf] Added the coarse grid optimization function.

View File

@ -45,7 +45,7 @@
/* then they will be checked for corner if they have ambiguity. */
#define CORNER_CHECK_EPSILON 32
#define COARSE_GRID_DIV 8
#define CG_DIMEN 8
/**************************************************************************
*
@ -2743,13 +2743,15 @@
FT_UInt width, rows, i, j;
FT_UInt c_width, c_rows;
FT_UInt sp_sq; /* max value to check */
FT_16D16 sp_sq; /* max value to check */
FT_16D16 cg_sq; /* max value to check for coarse grid */
FT_16D16 cg_max;
SDF_Contour* contours; /* list of all contours */
FT_Short* buffer; /* the bitmap buffer */
/* coarse grid to hold the list of edges */
SDF_Edge** coarse_grid[ COARSE_GRID_DIV * COARSE_GRID_DIV ];
SDF_Edge* coarse_grid[ CG_DIMEN * CG_DIMEN ];
if ( !shape || !bitmap )
{
@ -2770,11 +2772,6 @@
rows = bitmap->rows;
buffer = (FT_Short*)bitmap->buffer;
if ( USE_SQUARED_DISTANCES )
sp_sq = FT_INT_16D16( spread * spread );
else
sp_sq = FT_INT_16D16( spread );
if ( width == 0 || rows == 0 )
{
FT_TRACE0(( "[sdf] sdf_generate:\n"
@ -2785,8 +2782,21 @@
}
/* determine the dimension of the coarse grid */
c_width = width / COARSE_GRID_DIV + ( width % COARSE_GRID_DIV == 0 ? 0 : 1 );
c_rows = rows / COARSE_GRID_DIV + ( rows % COARSE_GRID_DIV == 0 ? 0 : 1 );
c_width = width / CG_DIMEN + ( width % CG_DIMEN == 0 ? 0 : 1 );
c_rows = rows / CG_DIMEN + ( rows % CG_DIMEN == 0 ? 0 : 1 );
cg_max = c_width > c_rows ? c_width : c_rows;
if ( USE_SQUARED_DISTANCES )
{
sp_sq = FT_INT_16D16( spread * spread );
cg_sq = sp_sq * 2;
}
else
{
sp_sq = FT_INT_16D16( spread );
cg_sq = sp_sq + FT_INT_16D16( cg_max / 2 );
}
/* if the coarse grid is too small then simply */
/* check all pixels against all the edges */
@ -2796,6 +2806,111 @@
goto Exit;
}
for ( j = 0; j < CG_DIMEN; j++ )
{
for ( i = 0; i < CG_DIMEN; i++ )
{
FT_Int cindex = j * CG_DIMEN + i;
SDF_Contour* cont = contours;
SDF_Edge* edge;
FT_26D6_Vec cpoint;
coarse_grid[cindex] = NULL;
cpoint.x = FT_INT_26D6( i ) + FT_INT_26D6( c_width / 2 );
cpoint.y = FT_INT_26D6( j ) + FT_INT_26D6( c_rows / 2 );
while ( cont )
{
edge = cont->edges;
while ( edge )
{
SDF_Signed_Distance dist;
SDF_Edge* temp;
FT_CALL( sdf_edge_get_min_distance( edge, cpoint, &dist ) );
if ( dist.distance > cg_sq )
{
edge = edge->next;
continue;
}
FT_CALL( sdf_edge_new( memory, &temp ) );
ft_memcpy( temp, edge, sizeof( *edge ) );
temp->next = coarse_grid[cindex];
coarse_grid[cindex] = temp;
edge = edge->next;
}
cont = cont->next;
}
}
}
for ( j = 0; j < CG_DIMEN; j++ )
{
for ( i = 0; i < CG_DIMEN; i++ )
{
FT_BBox sample_region;
FT_Int x, y;
if ( !coarse_grid[j * CG_DIMEN + i] ) continue;
sample_region.xMin = i * c_width;
sample_region.xMax = sample_region.xMin + c_width;
sample_region.yMin = j * c_rows;
sample_region.yMax = sample_region.yMin + c_rows;
for ( y = sample_region.yMin; y < sample_region.yMax; y++ )
{
for ( x = sample_region.xMin; x < sample_region.xMax; x++ )
{
FT_26D6_Vec current_pos;
SDF_Signed_Distance min_dist = max_sdf;
SDF_Edge* edges = coarse_grid[j * CG_DIMEN + i];
if ( x < 0 || x >= width ) continue;
if ( y < 0 || y >= rows ) continue;
current_pos.x = FT_INT_26D6( x ) + FT_INT_26D6( 1 ) / 2;
current_pos.y = FT_INT_26D6( y ) + FT_INT_26D6( 1 ) / 2;
while ( edges )
{
SDF_Signed_Distance dist;
FT_CALL( sdf_edge_get_min_distance( edges,
current_pos, &dist ) );
if ( dist.distance < min_dist.distance )
min_dist = dist;
edges = edges->next;
}
if ( min_dist.distance > sp_sq )
min_dist.distance = sp_sq;
if ( USE_SQUARED_DISTANCES )
min_dist.distance = square_root( min_dist.distance );
min_dist.distance /= 64;
buffer[ y * width + x ] = min_dist.distance;
}
}
}
}
Exit:
return error;
}
@ -2918,7 +3033,7 @@
FT_CALL( sdf_outline_decompose( outline, shape ) );
FT_CALL( sdf_generate_subdivision( shape, sdf_params->spread,
FT_CALL( sdf_generate_coarse_grid( shape, sdf_params->spread,
sdf_params->root.target ) );
Exit: