[PATCH 2/3] uxa: Simplify Composite solid acceleration for spans by only clipping once.

[Eric Anholt <eric@anholt.net>]

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.

Bug #37233.
---
 uxa/uxa-accel.c |   79 ++++++++++++++++--------------------------------------
 1 files changed, 24 insertions(+), 55 deletions(-)

diff --git a/uxa/uxa-accel.c b/uxa/uxa-accel.c
index 31c37e8..8f6da63 100644
--- a/uxa/uxa-accel.c
+++ b/uxa/uxa-accel.c
@@ -63,11 +63,9 @@ 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;
@@ -142,62 +140,35 @@ 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++;
 		}
 	}
 
@@ -240,10 +211,8 @@ 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++;
 		}
 	}
-- 
1.7.5.1