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[sdf -> bsdf] Optimize the first pass of the 8SED. 

* src/sdf/ftbsdf.c (first_pass): Optimize the first
  pass by first approximating the neighbor's distance
  by adding an offset. The offset will be max root(2)
  because the maximum be add to a vector is (1, 1).
  By approximating we can reduce the number of
  `FT_Vector_Length' calls and thus make the process
  faster.
This commit is contained in:
Anuj Verma 2020-07-26 17:05:49 +05:30 committed by anujverma
parent 6ccbf0ecf6
commit 6214e58893
2 changed files with 77 additions and 33 deletions
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12
[GSoC]ChangeLog
View File

@ -1,3 +1,15 @@
2020-07-26 Anuj Verma <anujv@iitbhilai.ac.in>
[sdf -> bsdf] Optimize the first pass of the 8SED.
* src/sdf/ftbsdf.c (first_pass): Optimize the first
pass by first approximating the neighbor's distance
by adding an offset. The offset will be max root(2)
because the maximum be add to a vector is (1, 1).
By approximating we can reduce the number of
`FT_Vector_Length' calls and thus make the process
faster.
2020-07-26 Anuj Verma <anujv@iitbhilai.ac.in>
[sdf] Fix GNU Make build.

98
src/sdf/ftbsdf.c
View File

@ -206,9 +206,9 @@
if ( s_i < 0 || s_i >= s_width ||
s_j < 0 || s_j >= s_rows )
{
t[t_index].near.x = 100000;
t[t_index].near.y = 100000;
t[t_index].dist = 100000;
t[t_index].near.x = FT_INT_MAX;
t[t_index].near.y = FT_INT_MAX;
t[t_index].dist = 128 * ONE;
continue;
}
@ -236,9 +236,9 @@
t[t_index].dist = 0;
else
{
t[t_index].near.x = 100000;
t[t_index].near.y = 100000;
t[t_index].dist = 100000;
t[t_index].near.x = FT_INT_MAX;
t[t_index].near.y = FT_INT_MAX;
t[t_index].dist = 128 * ONE;
}
#endif
@ -305,50 +305,75 @@
index = j * w + i;
current = dm + index;
/* While checking for nearest point we first */
/* approximate the dist of the `current' point */
/* by adding the deviation ( which will be root */
/* 2 max ). And if the new value is lesser than */
/* the current value then only we calculate the */
/* actual distances using `FT_Vector_Length'. */
/* Of course this will be eliminated while using */
/* squared distances. */
/* left-up */
to_check = current - w - 1;
dist_vec = to_check->near;
dist_vec.x -= ONE;
dist_vec.y -= ONE;
dist = FT_Vector_Length( &dist_vec );
dist = to_check->dist + 2 * ONE; /* will be root(2) but 2 is fine */
if ( dist < current->dist )
{
current->dist = dist;
current->near = dist_vec;
dist_vec = to_check->near;
dist_vec.x -= ONE;
dist_vec.y -= ONE;
dist = FT_Vector_Length( &dist_vec );
if ( dist < current->dist )
{
current->dist = dist;
current->near = dist_vec;
}
}
/* up */
to_check = current - w;
dist_vec = to_check->near;
dist_vec.y -= ONE;
dist = FT_Vector_Length( &dist_vec );
dist = to_check->dist + 1 * ONE; /* can only be 1 */
if ( dist < current->dist )
{
current->dist = dist;
current->near = dist_vec;
dist_vec = to_check->near;
dist_vec.y -= ONE;
dist = FT_Vector_Length( &dist_vec );
if ( dist < current->dist )
{
current->dist = dist;
current->near = dist_vec;
}
}
/* up-right */
to_check = current - w + 1;
dist_vec = to_check->near;
dist_vec.x += ONE;
dist_vec.y -= ONE;
dist = FT_Vector_Length( &dist_vec );
dist = to_check->dist + 2 * ONE;
if ( dist < current->dist )
{
current->dist = dist;
current->near = dist_vec;
dist_vec = to_check->near;
dist_vec.x += ONE;
dist_vec.y -= ONE;
dist = FT_Vector_Length( &dist_vec );
if ( dist < current->dist )
{
current->dist = dist;
current->near = dist_vec;
}
}
/* left */
to_check = current - 1;
dist_vec = to_check->near;
dist_vec.x -= ONE;
dist = FT_Vector_Length( &dist_vec );
dist = to_check->dist + 1 * ONE;
if ( dist < current->dist )
{
current->dist = dist;
current->near = dist_vec;
dist_vec = to_check->near;
dist_vec.x -= ONE;
dist = FT_Vector_Length( &dist_vec );
if ( dist < current->dist )
{
current->dist = dist;
current->near = dist_vec;
}
}
}
@ -361,13 +386,17 @@
/* right */
to_check = current + 1;
dist_vec = to_check->near;
dist_vec.x += ONE;
dist = FT_Vector_Length( &dist_vec );
dist = to_check->dist + 1 * ONE;
if ( dist < current->dist )
{
current->dist = dist;
current->near = dist_vec;
dist_vec = to_check->near;
dist_vec.x += ONE;
dist = FT_Vector_Length( &dist_vec );
if ( dist < current->dist )
{
current->dist = dist;
current->near = dist_vec;
}
}
}
}
@ -466,6 +495,9 @@
/* [TODO]: Assing the sign properly. */
if ( final_dist > worker->params.spread * 1024 )
final_dist = worker->params.spread * 1024;
t_buffer[index] = final_dist;
}
}