add the convolution filter from xserver to xorg

1 files changed, 30 insertions, 5 deletions

diff --git a/render/filter.c b/render/filter.c
index d1dbded6b..935c91515 100644
--- a/render/filter.c
+++ b/render/filter.c
@@ -47,8 +47,6 @@ static int  nfilterNames;
  * standard but not required filters don't have constant indices
  */
 
-int pictFilterConvolution;
-
 int
 PictureGetFilterId (char *filter, int len, Bool makeit)
 {
@@ -87,18 +85,21 @@ static Bool
 PictureSetDefaultIds (void)
 {
     /* careful here -- this list must match the #define values */
-    
+
     if (PictureGetFilterId (FilterNearest, -1, TRUE) != PictFilterNearest)
 	return FALSE;
     if (PictureGetFilterId (FilterBilinear, -1, TRUE) != PictFilterBilinear)
 	return FALSE;
-    
+
     if (PictureGetFilterId (FilterFast, -1, TRUE) != PictFilterFast)
 	return FALSE;
     if (PictureGetFilterId (FilterGood, -1, TRUE) != PictFilterGood)
 	return FALSE;
     if (PictureGetFilterId (FilterBest, -1, TRUE) != PictFilterBest)
 	return FALSE;
+
+    if (PictureGetFilterId (FilterConvolution, -1, TRUE) != PictFilterConvolution)
+	return FALSE;
     return TRUE;
 }
 
@@ -174,7 +175,7 @@ PictureSetFilterAlias (ScreenPtr pScreen, char *filter, char *alias)
 
 	if (ps->filterAliases)
 	    aliases = xrealloc (ps->filterAliases,
-				(ps->nfilterAliases + 1) * 
+				(ps->nfilterAliases + 1) *
 				sizeof (PictFilterAliasRec));
 	else
 	    aliases = xalloc (sizeof (PictFilterAliasRec));
@@ -212,6 +213,26 @@ PictureFindFilter (ScreenPtr pScreen, char *name, int len)
     return 0;
 }
 
+static Bool
+convolutionFilterValidateParams (PicturePtr pPicture,
+                                 int	   filter,
+                                 xFixed	   *params,
+                                 int	   nparams)
+{
+    if (nparams < 3)
+        return FALSE;
+
+    if (xFixedFrac (params[0]) || xFixedFrac (params[1]))
+        return FALSE;
+
+    nparams -= 2;
+    if ((xFixedToInt (params[0]) * xFixedToInt (params[1])) > nparams)
+        return FALSE;
+
+    return TRUE;
+}
+
+
 Bool
 PictureSetDefaultFilters (ScreenPtr pScreen)
 {
@@ -229,6 +250,10 @@ PictureSetDefaultFilters (ScreenPtr pScreen)
 	return FALSE;
     if (!PictureSetFilterAlias (pScreen, FilterBilinear, FilterBest))
 	return FALSE;
+
+    if (PictureAddFilter (pScreen, FilterConvolution, convolutionFilterValidateParams) < 0)
+        return FALSE;
+
     return TRUE;
 }