X-Git-Url: http://git.tdb.fi/?a=blobdiff_plain;f=source%2Fvertexformat.cpp;h=adb33c2afa48178d794a0476263a8d029f8519ac;hb=8ac93980ef87834fd431c97104baa441561a7ce0;hp=2b18178b26db4734bcc3e3f673abb32324a10779;hpb=f1cbab0dca940fd5db6d459f9e91661efe3d6052;p=libs%2Fgl.git

diff --git a/source/vertexformat.cpp b/source/vertexformat.cpp
index 2b18178b..adb33c2a 100644
--- a/source/vertexformat.cpp
+++ b/source/vertexformat.cpp
@@ -64,6 +64,30 @@ unsigned VertexFormat::stride() const
 	return s;
 }
 
+int VertexFormat::offset(VertexComponent comp, unsigned index) const
+{
+	if((comp<TEXCOORD1 && index>0) || (comp<ATTRIB1 && index>=8) || index>=53)
+		throw InvalidParameterValue("Vertex component index out of range");
+
+	unsigned type = (comp>>2)+index;
+	unsigned size = comp&3;
+	unsigned offs = 0;
+	for(const unsigned char *i=begin(); i!=end(); ++i)
+	{
+		if((*i>>2)==type)
+		{
+			if((*i&3)>=size)
+				return offs;
+			else
+				return -1;
+		}
+		else
+			offs += (*i&3)+1;
+	}
+
+	return -1;
+}
+
 VertexFormat operator,(const VertexFormat &f, VertexComponent c)
 {
 	VertexFormat r = f;