[Git][freetype/freetype][master] [raster] Simplify sweeping entry and ex

Alexei Podtelezhnikov pushed to branch master at FreeType / FreeType

Commits:

4e2d1f04

by Alexei Podtelezhnikov (Алексей Подтележников) at 2023-10-30T22:46:32-04:00

[raster] Simplify sweeping entry and exit.

* src/raster/ftraster.c (Draw_Sweep): Use y-turns to set the range,
correctly set the initial position, directly loop through y_turns,
and remove a 5-gray remnant at exit.

1 changed file:

src/raster/ftraster.c

Changes:

src/raster/ftraster.c

@@ -2604,67 +2604,46 @@
    static Bool
    Draw_Sweep( RAS_ARG )
+   {
 -    Int           min_Y, max_Y, top, bottom, dropouts;
 +    Int           min_Y, max_Y, dropouts;
      Int           y, y_change, y_height;
      PProfile      P, Q, P_Left, P_Right;
      Long          x1, x2, xs, e1, e2;
 -    TProfileList  waiting    = NULL;
 +    TProfileList  waiting    = ras.fProfile;
      TProfileList  draw_left  = NULL;
      TProfileList  draw_right = NULL;
 -    /* first, compute min and max Y */
 +    /* use y_turns to set the drawing range */
 -    P     = ras.fProfile;
 -    max_Y = (Int)TRUNC( ras.minY );
 -    min_Y = (Int)TRUNC( ras.maxY );
+-
 -    while ( P )
 -    {
 -      Q = P->link;
+-
 -      bottom = P->start;
 -      top    = P->start + P->height - 1;
+-
 -      if ( min_Y > bottom )
 -        min_Y = bottom;
 -      if ( max_Y < top )
 -        max_Y = top;
+-
 -      P->X = 0;
 -      InsNew( &waiting, P );
+-
 -      P = Q;
 -    }
 +    min_Y = (Int)ras.maxBuff[0];
 +    max_Y = (Int)ras.sizeBuff[-1] - 1;
      /* now initialize the sweep */
      ras.Proc_Sweep_Init( RAS_VARS min_Y, max_Y );
 -    /* then compute the distance of each profile from min_Y */
 +    /* set the activation countdowns and the initial positions */
      P = waiting;
+-
      while ( P )
+     {
        P->countL = P->start - min_Y;
 +      P->X      = P->x[P->offset];
++
        P = P->link;
+     }
 -    /* let's go */
 +    /* let's go, iterating through y_turns */
      y        = min_Y;
      y_height = 0;
 -    if ( ras.sizeBuff[-ras.numTurns] == min_Y )
 -      ras.numTurns--;
+-
 -    while ( ras.numTurns > 0 )
 +    while ( ++ras.maxBuff < ras.sizeBuff )
+     {
 -      /* check waiting list for new activations */
 +      /* check waiting list for new profile activations */
        P = waiting;
@@ -2690,7 +2669,7 @@
        Sort( &draw_left );
        Sort( &draw_right );
 -      y_change = (Int)ras.sizeBuff[-ras.numTurns--];
 +      y_change = (Int)*ras.maxBuff;
        y_height = y_change - y;
        while ( y < y_change )
@@ -2768,7 +2747,7 @@
+         }
+       }
 -      /* now finalize the profiles that need it */
 +      /* remove exhausted profiles */
        P = draw_left;
        while ( P )
@@ -2789,13 +2768,6 @@
+       }
+     }
 -    /* for gray-scaling, flush the bitmap scanline cache */
 -    while ( y <= max_Y )
 -    {
 -      ras.Proc_Sweep_Step( RAS_VAR );
 -      y++;
 -    }
+-
      return SUCCESS;
    Scan_DropOuts:

From:	Alexei Podtelezhnikov (@apodtele)
Subject:	[Git][freetype/freetype][master] [raster] Simplify sweeping entry and exit.
Date:	Tue, 31 Oct 2023 02:47:25 +0000