Patch

Defines a Bézier control patch. The array defines the control points for the patch.

        template Patch \
        { \
            < A3EB5D44-FC22-429D-9AFB-3221CB9719A6 > \
            DWORD nControlIndices; \
            array DWORD controlIndices[nControlIndices]; \
        }

Where:

nControlIndices - Number of control point indices.
array DWORD controlIndices[nControlIndices] - Array of control point indices.

The type of patch is defined by the number of control points, as shown in the following table.

Number of control points	Type
10	Cubic Bézier triangular patch
15	Quartic Bézier triangular patch
16	Cubic Bézier quad rectangle patch

The order of the control points are given in a spiral pattern, as shown in the following diagrams for triangular and rectangular patches.

Triangular patches used the following pattern.

Triangular patches

Rectangular patches use the following pattern.

Rectangular patches