ref: 8e8bb126d126affb36a2cfe9885f0c62711aa547
parent: 84b2c63374cb5444e927285ece93a24084674e48
author: Alexei Podtelezhnikov <[email protected]>
date: Fri Mar 18 19:21:59 EDT 2016
[smooth] Minor refactoring and microoptimizations. * src/smooth/ftgrays.c (gray_render_conic, gray_render_cubic): Move band clipping from here. (gray_conic_to, gray_cubic_to): ... to here. (gray_rander_line, gray_render_scanline): Initialize variables closer to their use.
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,10 +1,20 @@
+2016-03-18 Alexei Podtelezhnikov <[email protected]>
+
+ [smooth] Minor refactoring and microoptimizations.
+
+ * src/smooth/ftgrays.c (gray_render_conic, gray_render_cubic): Move
+ band clipping from here.
+ (gray_conic_to, gray_cubic_to): ... to here.
+ (gray_rander_line, gray_render_scanline): Initialize variables closer
+ to their use.
+
2016-03-17 Alexei Podtelezhnikov <[email protected]>
[smooth] Minor refactoring.
* src/smooth/ftgrays.c (gray_render_conic, gray_render_cubic): Move
- upscaling from here...
- (gray_conic_to, gray_cubic_to):... to here.
+ upscaling from here.
+ (gray_conic_to, gray_cubic_to): ... to here.
2016-03-15 Werner Lemberg <[email protected]>
--- a/src/smooth/ftgrays.c
+++ b/src/smooth/ftgrays.c
@@ -689,12 +689,8 @@
int incr;
- dx = x2 - x1;
-
ex1 = TRUNC( x1 );
ex2 = TRUNC( x2 );
- fx1 = (TCoord)( x1 - SUBPIXELS( ex1 ) );
- fx2 = (TCoord)( x2 - SUBPIXELS( ex2 ) );
/* trivial case. Happens often */
if ( y1 == y2 )
@@ -703,6 +699,9 @@
return;
}
+ fx1 = (TCoord)( x1 - SUBPIXELS( ex1 ) );
+ fx2 = (TCoord)( x2 - SUBPIXELS( ex2 ) );
+
/* everything is located in a single cell. That is easy! */
/* */
if ( ex1 == ex2 )
@@ -716,6 +715,7 @@
/* ok, we'll have to render a run of adjacent cells on the same */
/* scanline... */
/* */
+ dx = x2 - x1;
p = ( ONE_PIXEL - fx1 ) * ( y2 - y1 );
first = ONE_PIXEL;
incr = 1;
@@ -787,17 +787,15 @@
ey1 = TRUNC( ras.y );
ey2 = TRUNC( to_y ); /* if (ey2 >= ras.max_ey) ey2 = ras.max_ey-1; */
- fy1 = (TCoord)( ras.y - SUBPIXELS( ey1 ) );
- fy2 = (TCoord)( to_y - SUBPIXELS( ey2 ) );
- dx = to_x - ras.x;
- dy = to_y - ras.y;
-
/* perform vertical clipping */
if ( ( ey1 >= ras.max_ey && ey2 >= ras.max_ey ) ||
( ey1 < ras.min_ey && ey2 < ras.min_ey ) )
goto End;
+ fy1 = (TCoord)( ras.y - SUBPIXELS( ey1 ) );
+ fy2 = (TCoord)( to_y - SUBPIXELS( ey2 ) );
+
/* everything is on a single scanline */
if ( ey1 == ey2 )
{@@ -805,6 +803,9 @@
goto End;
}
+ dx = to_x - ras.x;
+ dy = to_y - ras.y;
+
/* vertical line - avoid calling gray_render_scanline */
incr = 1;
@@ -918,8 +919,6 @@
TCoord ex1, ex2, ey1, ey2;
- ex1 = TRUNC( ras.x );
- ex2 = TRUNC( to_x );
ey1 = TRUNC( ras.y );
ey2 = TRUNC( to_y );
@@ -928,12 +927,15 @@
( ey1 < ras.min_ey && ey2 < ras.min_ey ) )
goto End;
- dx = to_x - ras.x;
- dy = to_y - ras.y;
+ ex1 = TRUNC( ras.x );
+ ex2 = TRUNC( to_x );
fx1 = ras.x - SUBPIXELS( ex1 );
fy1 = ras.y - SUBPIXELS( ey1 );
+ dx = to_x - ras.x;
+ dy = to_y - ras.y;
+
if ( ex1 == ex2 && ey1 == ey2 ) /* inside one cell */
;
else if ( dy == 0 ) /* ex1 != ex2 */ /* any horizontal line */
@@ -1066,7 +1068,6 @@
gray_render_conic( RAS_ARG )
{TPos dx, dy;
- TPos min, max, y;
int top, level;
int* levels = ras.lev_stack;
FT_Vector* arc = ras.bez_stack;
@@ -1082,20 +1083,6 @@
if ( dx < ONE_PIXEL / 4 )
goto Draw;
- /* short-cut the arc that crosses the current band */
- min = max = arc[0].y;
-
- y = arc[1].y;
- if ( y < min ) min = y;
- if ( y > max ) max = y;
-
- y = arc[2].y;
- if ( y < min ) min = y;
- if ( y > max ) max = y;
-
- if ( TRUNC( min ) >= ras.max_ey || TRUNC( max ) < ras.min_ey )
- goto Draw;
-
level = 0;
do
{@@ -1158,33 +1145,11 @@
gray_render_cubic( RAS_ARG )
{FT_Vector* arc = ras.bez_stack;
- TPos min, max, y;
+ TPos dx, dy, dx_, dy_;
+ TPos dx1, dy1, dx2, dy2;
+ TPos L, s, s_limit;
- /* Short-cut the arc that crosses the current band. */
- min = max = arc[0].y;
-
- y = arc[1].y;
- if ( y < min )
- min = y;
- if ( y > max )
- max = y;
-
- y = arc[2].y;
- if ( y < min )
- min = y;
- if ( y > max )
- max = y;
-
- y = arc[3].y;
- if ( y < min )
- min = y;
- if ( y > max )
- max = y;
-
- if ( TRUNC( min ) >= ras.max_ey || TRUNC( max ) < ras.min_ey )
- goto Draw;
-
for (;;)
{/* Decide whether to split or draw. See `Rapid Termination */
@@ -1192,58 +1157,42 @@
/* F. Hain, at */
/* http://www.cis.southalabama.edu/~hain/general/Publications/Bezier/Camera-ready%20CISST02%202.pdf */
- {- TPos dx, dy, dx_, dy_;
- TPos dx1, dy1, dx2, dy2;
- TPos L, s, s_limit;
+ /* dx and dy are x and y components of the P0-P3 chord vector. */
+ dx = dx_ = arc[3].x - arc[0].x;
+ dy = dy_ = arc[3].y - arc[0].y;
+ L = FT_HYPOT( dx_, dy_ );
- /* dx and dy are x and y components of the P0-P3 chord vector. */
- dx = dx_ = arc[3].x - arc[0].x;
- dy = dy_ = arc[3].y - arc[0].y;
+ /* Avoid possible arithmetic overflow below by splitting. */
+ if ( L > 32767 )
+ goto Split;
- L = FT_HYPOT( dx_, dy_ );
+ /* Max deviation may be as much as (s/L) * 3/4 (if Hain's v = 1). */
+ s_limit = L * (TPos)( ONE_PIXEL / 6 );
- /* Avoid possible arithmetic overflow below by splitting. */
- if ( L > 32767 )
- goto Split;
+ /* s is L * the perpendicular distance from P1 to the line P0-P3. */
+ dx1 = arc[1].x - arc[0].x;
+ dy1 = arc[1].y - arc[0].y;
+ s = FT_ABS( dy * dx1 - dx * dy1 );
- /* Max deviation may be as much as (s/L) * 3/4 (if Hain's v = 1). */
- s_limit = L * (TPos)( ONE_PIXEL / 6 );
+ if ( s > s_limit )
+ goto Split;
- /* s is L * the perpendicular distance from P1 to the line P0-P3. */
- dx1 = arc[1].x - arc[0].x;
- dy1 = arc[1].y - arc[0].y;
- s = FT_ABS( dy * dx1 - dx * dy1 );
+ /* s is L * the perpendicular distance from P2 to the line P0-P3. */
+ dx2 = arc[2].x - arc[0].x;
+ dy2 = arc[2].y - arc[0].y;
+ s = FT_ABS( dy * dx2 - dx * dy2 );
- if ( s > s_limit )
- goto Split;
+ if ( s > s_limit )
+ goto Split;
- /* s is L * the perpendicular distance from P2 to the line P0-P3. */
- dx2 = arc[2].x - arc[0].x;
- dy2 = arc[2].y - arc[0].y;
- s = FT_ABS( dy * dx2 - dx * dy2 );
+ /* Split super curvy segments where the off points are so far
+ from the chord that the angles P0-P1-P3 or P0-P2-P3 become
+ acute as detected by appropriate dot products. */
+ if ( dx1 * ( dx1 - dx ) + dy1 * ( dy1 - dy ) > 0 ||
+ dx2 * ( dx2 - dx ) + dy2 * ( dy2 - dy ) > 0 )
+ goto Split;
- if ( s > s_limit )
- goto Split;
-
- /* Split super curvy segments where the off points are so far
- from the chord that the angles P0-P1-P3 or P0-P2-P3 become
- acute as detected by appropriate dot products. */
- if ( dx1 * ( dx1 - dx ) + dy1 * ( dy1 - dy ) > 0 ||
- dx2 * ( dx2 - dx ) + dy2 * ( dy2 - dy ) > 0 )
- goto Split;
-
- /* No reason to split. */
- goto Draw;
- }
-
- Split:
- gray_split_cubic( arc );
- arc += 3;
- continue;
-
- Draw:
gray_render_line( RAS_VAR_ arc[0].x, arc[0].y );
if ( arc == ras.bez_stack )
@@ -1250,6 +1199,11 @@
return;
arc -= 3;
+ continue;
+
+ Split:
+ gray_split_cubic( arc );
+ arc += 3;
}
}
@@ -1292,6 +1246,8 @@
gray_PWorker worker )
{FT_Vector* arc = ras.bez_stack;
+ TPos min = SUBPIXELS( ras.min_ey );
+ TPos max = SUBPIXELS( ras.max_ey );
arc[0].x = UPSCALE( to->x );
@@ -1301,7 +1257,17 @@
arc[2].x = ras.x;
arc[2].y = ras.y;
- gray_render_conic( RAS_VAR );
+ /* only render arc inside the current band */
+ if ( ( min <= arc[0].y && arc[0].y < max ) ||
+ ( min <= arc[1].y && arc[1].y < max ) ||
+ ( min <= arc[2].y && arc[2].y < max ) )
+ gray_render_conic( RAS_VAR );
+ else
+ {+ ras.x = arc[0].x;
+ ras.y = arc[0].y;
+ }
+
return 0;
}
@@ -1313,6 +1279,8 @@
gray_PWorker worker )
{FT_Vector* arc = ras.bez_stack;
+ TPos min = SUBPIXELS( ras.min_ey );
+ TPos max = SUBPIXELS( ras.max_ey );
arc[0].x = UPSCALE( to->x );
@@ -1324,7 +1292,18 @@
arc[3].x = ras.x;
arc[3].y = ras.y;
- gray_render_cubic( RAS_VAR );
+ /* only render arc inside the current band */
+ if ( ( min <= arc[0].y && arc[0].y < max ) ||
+ ( min <= arc[1].y && arc[1].y < max ) ||
+ ( min <= arc[2].y && arc[2].y < max ) ||
+ ( min <= arc[3].y && arc[3].y < max ) )
+ gray_render_cubic( RAS_VAR );
+ else
+ {+ ras.x = arc[0].x;
+ ras.y = arc[0].y;
+ }
+
return 0;
}