Preload XObject group attributes properly, including transparency.

3 files changed, 35 insertions, 18 deletions

diff --git a/mupdf/mupdf.h b/mupdf/mupdf.h
index 9100edee..bd19bf14 100644
--- a/mupdf/mupdf.h
+++ b/mupdf/mupdf.h
@@ -277,6 +277,7 @@ struct pdf_xobject_s
 	fz_rect bbox;
 	int isolated;
 	int knockout;
+	int transparency;
 	fz_obj *resources;
 	fz_buffer *contents;
 };
diff --git a/mupdf/pdf_interpret.c b/mupdf/pdf_interpret.c
index 7b6c5b9d..e55f029e 100644
--- a/mupdf/pdf_interpret.c
+++ b/mupdf/pdf_interpret.c
@@ -155,7 +155,7 @@ pdf_dropcsi(pdf_csi *csi)
  */
 
 static fz_error
-runxobject(pdf_csi *csi, pdf_xref *xref, pdf_xobject *xobj, int istransparency)
+runxobject(pdf_csi *csi, pdf_xref *xref, pdf_xobject *xobj)
 {
 	fz_error error;
 	fz_node *transform;
@@ -174,7 +174,7 @@ runxobject(pdf_csi *csi, pdf_xref *xref, pdf_xobject *xobj, int istransparency)
 	gstate->fill.parentalpha = gstate->fill.alpha;
 
 	/* reset alpha to 1.0 when starting a new Transparency group */
-	if (istransparency)
+	if (xobj->transparency)
 	{
 	    gstate->stroke.alpha = gstate->stroke.parentalpha;
 	    gstate->fill.alpha = gstate->fill.parentalpha;
@@ -919,23 +919,12 @@ Lsetcolor:
 
 			if (xobj)
 			{
-				int istransparency = 0;
-
 				/* Inherit parent resources, in case this one was empty */
 				if (!xobj->resources)
 					xobj->resources = fz_keepobj(rdb);
 
 				clearstack(csi);
-				/* check if it is a Transparency group */
-				obj = fz_dictgets(dict, "Group");
-				if (obj) {
-					obj = fz_dictgets(obj, "S");
-
-					if (!strcmp(fz_toname(obj), "Transparency"))
-						istransparency = 1;
-				}
-
-				error = runxobject(csi, xref, xobj, istransparency);
+				error = runxobject(csi, xref, xobj);
 				if (error)
 					return fz_rethrow(error, "cannot draw xobject");
 			}
diff --git a/mupdf/pdf_xobject.c b/mupdf/pdf_xobject.c
index 8bb802a5..7c425fc0 100644
--- a/mupdf/pdf_xobject.c
+++ b/mupdf/pdf_xobject.c
@@ -51,13 +51,40 @@ pdf_loadxobject(pdf_xobject **formp, pdf_xref *xref, fz_obj *dict, fz_obj *ref)
 			form->matrix.c, form->matrix.d,
 			form->matrix.e, form->matrix.f);
 
-	obj = fz_dictgets(dict, "I");
-	form->isolated = fz_tobool(obj);
-	obj = fz_dictgets(dict, "K");
-	form->knockout = fz_tobool(obj);
+	form->isolated = 0;
+	form->knockout = 0;
+	form->transparency = 0;
+
+	obj = fz_dictgets(dict, "Group");
+	if (obj)
+	{
+		fz_obj *attrs = obj;
+
+		error = pdf_resolve(&attrs, xref);
+		if (error)
+		{
+			fz_dropobj(attrs);
+			error = fz_rethrow(error, "cannot resolve xobject group attributes");
+			goto cleanup;
+		}
+
+		obj = fz_dictgets(attrs, "I");
+		form->isolated = fz_tobool(obj);
+		obj = fz_dictgets(attrs, "K");
+		form->knockout = fz_tobool(obj);
+
+		obj = fz_dictgets(attrs, "S");
+		if (!strcmp(fz_toname(obj), "Transparency"))
+		{
+			form->transparency = 1;
+		}
+
+		fz_dropobj(attrs);
+	}
 
 	pdf_logrsrc("isolated %d\n", form->isolated);
 	pdf_logrsrc("knockout %d\n", form->knockout);
+	pdf_logrsrc("transparency %d\n", form->transparency);
 
 	obj = fz_dictgets(dict, "Resources");
 	if (obj)