From 3c1d5bc35e02dfd8234c029dcab5661e1656ca8e Mon Sep 17 00:00:00 2001
From: Chris Wilson <chris@chris-wilson.co.uk>
Date: Fri, 24 Jun 2011 00:34:11 +0100
Subject: [PATCH] sna: Clip the fbcon to the frontbuffer

...both to correct the placement of the fbcon into the smaller scanout and
to ensure that we correctly clip the boxes to be copied.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
---
 src/sna/sna_display.c | 24 ++++++++++++++++++------
 1 file changed, 18 insertions(+), 6 deletions(-)

diff --git a/src/sna/sna_display.c b/src/sna/sna_display.c
index cb1beba7..f92a1dbf 100644
--- a/src/sna/sna_display.c
+++ b/src/sna/sna_display.c
@@ -502,6 +502,8 @@ void sna_copy_fbcon(struct sna *sna)
 	struct kgem_bo *bo;
 	BoxRec box;
 	bool ok;
+	int sx, sy;
+	int dx, dy;
 	int i;
 
 	if (sna->kgem.wedged)
@@ -527,8 +529,8 @@ void sna_copy_fbcon(struct sna *sna)
 		goto cleanup_fbcon;
 
 	box.x1 = box.y1 = 0;
-	box.x2 = fbcon->width;
-	box.y2 = fbcon->height;
+	box.x2 = min(fbcon->width, sna->front->drawable.width);
+	box.y2 = min(fbcon->height, sna->front->drawable.height);
 
 	bo = sna_create_bo_for_fbcon(sna, fbcon);
 	if (bo == NULL)
@@ -537,11 +539,21 @@ void sna_copy_fbcon(struct sna *sna)
 	priv = sna_pixmap(sna->front);
 	assert(priv && priv->gpu_bo);
 
+	sx = dx = 0;
+	if (box.x2 < fbcon->width)
+		sx = (fbcon->width - box.x2) / 2.;
+	if (box.x2 < sna->front->drawable.width)
+		dx = (sna->front->drawable.width - box.x2) / 2.;
+
+	sy = dy = 0;
+	if (box.y2 < fbcon->height)
+		sy = (fbcon->height - box.y2) / 2.;
+	if (box.y2 < sna->front->drawable.height)
+		dy = (sna->front->drawable.height - box.y2) / 2.;
+
 	ok = sna->render.copy_boxes(sna, GXcopy,
-				    sna->front, bo, 0, 0,
-				    sna->front, priv->gpu_bo,
-				    (sna->front->drawable.width - fbcon->width)/2,
-				    (sna->front->drawable.height - fbcon->height)/2,
+				    sna->front, bo, sx, sy,
+				    sna->front, priv->gpu_bo, dx, dy,
 				    &box, 1);
 	sna_damage_add_box(&priv->gpu_damage, &box);