uxa: Simplify Composite solid acceleration for spans by only clipping once.

Unlike the previous commit removing this style of code, the code in
this one was originally wrong, and would fail to clip in the second
pass of clipping when y was > pbox->y2.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=37233
Reviewed-by: Keith Packard <keithp@keithp.com>
(cherry picked from commit e0066e77e026b0dd0daa0c3765473c7d63aa6753)

Signed-off-by: Owain G. Ainsworth <oga@openbsd.org>

1 files changed, 24 insertions, 55 deletions

diff --git a/uxa/uxa-accel.c b/uxa/uxa-accel.c
index 18131127..62fa3cce 100644
--- a/uxa/uxa-accel.c
+++ b/uxa/uxa-accel.c
@@ -61,11 +61,9 @@ uxa_fill_spans(DrawablePtr pDrawable, GCPtr pGC, int n,
 	uxa_screen_t *uxa_screen = uxa_get_screen(screen);
 	RegionPtr pClip = fbGetCompositeClip(pGC);
 	PixmapPtr dst_pixmap, src_pixmap = NULL;
-	BoxPtr pextent, pbox;
+	BoxPtr pbox;
 	int nbox;
-	int extentX1, extentX2, extentY1, extentY2;
-	int x1, x2, y, fullX1, fullX2, fullY1;
-	int partX1, partX2;
+	int x1, x2, y;
 	int off_x, off_y;
 	xRenderColor color;
 	PictFormatPtr format;
@@ -140,62 +138,35 @@ uxa_fill_spans(DrawablePtr pDrawable, GCPtr pGC, int n,
 		goto solid;
 	}
 
-	pextent = REGION_EXTENTS(pGC->screen, pClip);
-	extentX1 = pextent->x1;
-	extentY1 = pextent->y1;
-	extentX2 = pextent->x2;
-	extentY2 = pextent->y2;
 	while (n--) {
-		fullX1 = ppt->x;
-		fullY1 = ppt->y;
-		fullX2 = fullX1 + (int)*pwidth;
+		x1 = ppt->x;
+		y = ppt->y;
+		x2 = x1 + (int)*pwidth;
 		ppt++;
 		pwidth++;
 
-		if (fullY1 < extentY1 || extentY2 <= fullY1)
-			continue;
+		nbox = REGION_NUM_RECTS(pClip);
+		pbox = REGION_RECTS(pClip);
+		while (nbox--) {
+			if (pbox->y1 > y || pbox->y2 <= y)
+				continue;
 
-		if (fullX1 < extentX1)
-			fullX1 = extentX1;
+			if (x1 < pbox->x1)
+				x1 = pbox->x1;
 
-		if (fullX2 > extentX2)
-			fullX2 = extentX2;
+			if (x2 > pbox->x2)
+				x2 = pbox->x2;
 
-		if (fullX1 >= fullX2)
-			continue;
+			if (x2 <= x1)
+				continue;
 
-		nbox = REGION_NUM_RECTS(pClip);
-		if (nbox == 1) {
 			uxa_screen->info->composite(dst_pixmap,
-						    0, 0, 0, 0,
-						    fullX1 + off_x,
-						    fullY1 + off_y,
-						    fullX2 - fullX1, 1);
-		} else {
-			pbox = REGION_RECTS(pClip);
-			while (nbox--) {
-				if (pbox->y1 > fullY1)
-					break;
-
-				if (pbox->y1 <= fullY1) {
-					partX1 = pbox->x1;
-					if (partX1 < fullX1)
-						partX1 = fullX1;
-
-					partX2 = pbox->x2;
-					if (partX2 > fullX2)
-						partX2 = fullX2;
-
-					if (partX2 > partX1) {
-						uxa_screen->info->composite(dst_pixmap,
-									    0, 0, 0, 0,
-									    partX1 + off_x,
-									    fullY1 + off_y,
-									    partX2 - partX1, 1);
-					}
-				}
-				pbox++;
-			}
+						    0, 0,
+						    0, 0,
+						    x1 + off_x, y + off_y,
+						    x2 - x1, 1);
+
+			pbox++;
 		}
 	}
 
@@ -238,10 +209,8 @@ solid:
 				continue;
 
 			(*uxa_screen->info->solid) (dst_pixmap,
-						    x1 + off_x,
-						    y + off_y,
-						    x2 + off_x,
-						    y + 1 + off_y);
+						    x1 + off_x, y + off_y,
+						    x2 + off_x, y + 1 + off_y);
 			pbox++;
 		}
 	}