     vec3 Em;
     vec3 Fp;
     vec3 Fm;
-    vec4 patchCoord;
+    centroid vec4 patchCoord;
     ivec4 ptexInfo;
 #if OSD_NUM_VARYINGS > 0
     float varyings[OSD_NUM_VARYINGS];

    vec4 position;
    vec3 normal;
    vec3 tangent;
    vec4 patchCoord; // u, v, level, faceID
    noperspective vec4 edgeDistance;
#if OSD_NUM_VARYINGS > 0
    float varyings[OSD_NUM_VARYINGS];


struct ControlVertex {
    vec4 position;
    centroid vec4 patchCoord; // u, v, level, faceID
    ivec4 ptexInfo;  // U offset, V offset, 2^ptexlevel', rotation
    ivec3 clipFlag;
#if OSD_NUM_VARYINGS > 0
