[gtk-vnc] When using 32bpp, depth 24 fill alpha byte.

[Daniel P. Berrange <dberrange src gnome org>]

commit 3def8ff205c3e36631dfcb2b7bcccd1605e37d6f
Author: Daniel P. Berrange <dan berrange com>
Date:   Mon Jul 5 21:45:04 2010 +0100

    When using 32bpp, depth 24 fill alpha byte.
    
    When constructing a GdkPixbuf from the framebuffer pixel array,
    it will expect the alpha bits to be initialized to a sensible
    value. Since we don't care about alpha, make sure 32bpp, depth 24
    format sets alpha to 0xff (full opaque).

 src/vncbaseframebuffer.c    |    6 +++++-
 src/vncbaseframebufferblt.h |    6 ++++--
 2 files changed, 9 insertions(+), 3 deletions(-)
---
diff --git a/src/vncbaseframebuffer.c b/src/vncbaseframebuffer.c
index 99fc5ef..689b469 100644
--- a/src/vncbaseframebuffer.c
+++ b/src/vncbaseframebuffer.c
@@ -65,6 +65,7 @@ struct _VncBaseFramebufferPrivate {
 	int rm, gm, bm;
         int rrs, grs, brs;
         int rls, gls, bls;
+	int alpha_mask;
 
 	/* TRUE if localFormat == remoteFormat */
         gboolean perfect_match;
@@ -848,7 +849,10 @@ static void vnc_base_framebuffer_reinit_render_funcs(VncBaseFramebuffer *fb)
 	i = priv->remoteFormat->bits_per_pixel / 8;
 	j = priv->localFormat->bits_per_pixel / 8;
 	if (i == 4) i = 3;
-	if (j == 4) j = 3;
+	if (j == 4) {
+		j = 3;
+		priv->alpha_mask = 0xff000000;
+	}
 	if (i > 4) i = 4; /* XXX hardcoding int64 */
 	if (j > 4) j = 4; /* XXX hardcoding int64 */
 	if (!priv->remoteFormat->true_color_flag) {
diff --git a/src/vncbaseframebufferblt.h b/src/vncbaseframebufferblt.h
index 1873cd1..0a7a1c8 100644
--- a/src/vncbaseframebufferblt.h
+++ b/src/vncbaseframebufferblt.h
@@ -60,7 +60,8 @@ static void SET_PIXEL(VncBaseFramebufferPrivate *priv,
 			     spidx,
 			     &red, &green, &blue);
 	sp = ((guint64)red << 32) | ((guint64)green << 16) | (guint64)blue;
-	*dp = SWAP_IMG(priv, ((sp >> priv->rrs) & priv->rm) << priv->rls
+	*dp = SWAP_IMG(priv, priv->alpha_mask
+		       | ((sp >> priv->rrs) & priv->rm) << priv->rls
 		       | ((sp >> priv->grs) & priv->gm) << priv->gls
 		       | ((sp >> priv->brs) & priv->bm) << priv->bls);
 }
@@ -68,7 +69,8 @@ static void SET_PIXEL(VncBaseFramebufferPrivate *priv,
 static void SET_PIXEL(VncBaseFramebufferPrivate *priv,
 		      dst_pixel_t *dp, src_pixel_t sp)
 {
-	*dp = SWAP_IMG(priv, ((sp >> priv->rrs) & priv->rm) << priv->rls
+	*dp = SWAP_IMG(priv, priv->alpha_mask
+		       | ((sp >> priv->rrs) & priv->rm) << priv->rls
 		       | ((sp >> priv->grs) & priv->gm) << priv->gls
 		       | ((sp >> priv->brs) & priv->bm) << priv->bls);
 }