From bc3b5281ed08d1cae3a2d881d2c72d0e98e57c05 Mon Sep 17 00:00:00 2001 From: Alexei Podtelezhnikov Date: Wed, 8 May 2019 22:08:40 -0400 Subject: [PATCH] [smooth] Faster fractions. * src/smooth/ftgrays.c (SUBPIXELS): Replace with... (FRACT): A fractional coordinate macro to use in... (gray_render_line, gray_render_scanline): ... here. --- ChangeLog | 8 ++++++++ src/smooth/ftgrays.c | 43 ++++++++++++++++++++++--------------------- 2 files changed, 30 insertions(+), 21 deletions(-) diff --git a/ChangeLog b/ChangeLog index d68323aee..ab6d30231 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,11 @@ +2019-05-08 Alexei Podtelezhnikov + + [smooth] Faster fractions. + + * src/smooth/ftgrays.c (SUBPIXELS): Replace with... + (FRACT): A fractional coordinate macro to use in... + (gray_render_line, gray_render_scanline): ... here. + 2019-05-07 Alexei Podtelezhnikov * src/raster/ftraster.c (Draw_Sweep): Unbreak. diff --git a/src/smooth/ftgrays.c b/src/smooth/ftgrays.c index b09bcceb6..8f87f8483 100644 --- a/src/smooth/ftgrays.c +++ b/src/smooth/ftgrays.c @@ -328,8 +328,8 @@ typedef ptrdiff_t FT_PtrDist; #define PIXEL_BITS 8 #define ONE_PIXEL ( 1 << PIXEL_BITS ) -#define TRUNC( x ) ( (TCoord)( (x) >> PIXEL_BITS ) ) -#define SUBPIXELS( x ) ( (TPos)(x) * ONE_PIXEL ) +#define TRUNC( x ) (TCoord)( (x) >> PIXEL_BITS ) +#define FRACT( x ) (TCoord)( (x) & ( ONE_PIXEL - 1 ) ) #if PIXEL_BITS >= 6 #define UPSCALE( x ) ( (x) * ( ONE_PIXEL >> 6 ) ) @@ -380,9 +380,9 @@ typedef ptrdiff_t FT_PtrDist; #define FT_UDIVPREP( c, b ) \ long b ## _r = c ? (long)( FT_ULONG_MAX >> PIXEL_BITS ) / ( b ) \ : 0 -#define FT_UDIV( a, b ) \ - ( ( (unsigned long)( a ) * (unsigned long)( b ## _r ) ) >> \ - ( sizeof( long ) * FT_CHAR_BIT - PIXEL_BITS ) ) +#define FT_UDIV( a, b ) \ + (TCoord)( ( (unsigned long)( a ) * (unsigned long)( b ## _r ) ) >> \ + ( sizeof( long ) * FT_CHAR_BIT - PIXEL_BITS ) ) /************************************************************************** @@ -610,8 +610,8 @@ typedef ptrdiff_t FT_PtrDist; return; } - fx1 = (TCoord)( x1 - SUBPIXELS( ex1 ) ); - fx2 = (TCoord)( x2 - SUBPIXELS( ex2 ) ); + fx1 = FRACT( x1 ); + fx2 = FRACT( x2 ); /* everything is located in a single cell. That is easy! */ /* */ @@ -703,8 +703,8 @@ typedef ptrdiff_t FT_PtrDist; ( ey1 < ras.min_ey && ey2 < ras.min_ey ) ) goto End; - fy1 = (TCoord)( ras.y - SUBPIXELS( ey1 ) ); - fy2 = (TCoord)( to_y - SUBPIXELS( ey2 ) ); + fy1 = FRACT( ras.y ); + fy2 = FRACT( to_y ); /* everything is on a single scanline */ if ( ey1 == ey2 ) @@ -720,7 +720,7 @@ typedef ptrdiff_t FT_PtrDist; if ( dx == 0 ) { TCoord ex = TRUNC( ras.x ); - TCoord two_fx = (TCoord)( ( ras.x - SUBPIXELS( ex ) ) << 1 ); + TCoord two_fx = FRACT( ras.x ) << 1; TArea area; @@ -831,8 +831,9 @@ typedef ptrdiff_t FT_PtrDist; gray_render_line( RAS_ARG_ TPos to_x, TPos to_y ) { - TPos dx, dy, fx1, fy1, fx2, fy2; - TCoord ex1, ex2, ey1, ey2; + TPos dx, dy; + TCoord fx1, fy1, fx2, fy2; + TCoord ex1, ey1, ex2, ey2; ey1 = TRUNC( ras.y ); @@ -846,8 +847,8 @@ typedef ptrdiff_t FT_PtrDist; ex1 = TRUNC( ras.x ); ex2 = TRUNC( to_x ); - fx1 = ras.x - SUBPIXELS( ex1 ); - fy1 = ras.y - SUBPIXELS( ey1 ); + fx1 = FRACT( ras.x ); + fy1 = FRACT( ras.y ); dx = to_x - ras.x; dy = to_y - ras.y; @@ -884,7 +885,7 @@ typedef ptrdiff_t FT_PtrDist; } else /* any other line */ { - TPos prod = dx * fy1 - dy * fx1; + TPos prod = dx * (TPos)fy1 - dy * (TPos)fx1; FT_UDIVPREP( ex1 != ex2, dx ); FT_UDIVPREP( ey1 != ey2, dy ); @@ -898,7 +899,7 @@ typedef ptrdiff_t FT_PtrDist; prod - dx * ONE_PIXEL > 0 ) /* left */ { fx2 = 0; - fy2 = (TPos)FT_UDIV( -prod, -dx ); + fy2 = FT_UDIV( -prod, -dx ); prod -= dy * ONE_PIXEL; ras.cover += ( fy2 - fy1 ); ras.area += ( fy2 - fy1 ) * ( fx1 + fx2 ); @@ -910,7 +911,7 @@ typedef ptrdiff_t FT_PtrDist; prod - dx * ONE_PIXEL + dy * ONE_PIXEL > 0 ) /* up */ { prod -= dx * ONE_PIXEL; - fx2 = (TPos)FT_UDIV( -prod, dy ); + fx2 = FT_UDIV( -prod, dy ); fy2 = ONE_PIXEL; ras.cover += ( fy2 - fy1 ); ras.area += ( fy2 - fy1 ) * ( fx1 + fx2 ); @@ -923,7 +924,7 @@ typedef ptrdiff_t FT_PtrDist; { prod += dy * ONE_PIXEL; fx2 = ONE_PIXEL; - fy2 = (TPos)FT_UDIV( prod, dx ); + fy2 = FT_UDIV( prod, dx ); ras.cover += ( fy2 - fy1 ); ras.area += ( fy2 - fy1 ) * ( fx1 + fx2 ); fx1 = 0; @@ -933,7 +934,7 @@ typedef ptrdiff_t FT_PtrDist; else /* ( prod + dy * ONE_PIXEL < 0 && prod > 0 ) down */ { - fx2 = (TPos)FT_UDIV( prod, -dy ); + fx2 = FT_UDIV( prod, -dy ); fy2 = 0; prod += dx * ONE_PIXEL; ras.cover += ( fy2 - fy1 ); @@ -947,8 +948,8 @@ typedef ptrdiff_t FT_PtrDist; } while ( ex1 != ex2 || ey1 != ey2 ); } - fx2 = to_x - SUBPIXELS( ex2 ); - fy2 = to_y - SUBPIXELS( ey2 ); + fx2 = FRACT( to_x ); + fy2 = FRACT( to_y ); ras.cover += ( fy2 - fy1 ); ras.area += ( fy2 - fy1 ) * ( fx1 + fx2 );