void CHWTessellator::TriGenerateConnectivity()

in d3d/archive/images/d3d11/tessellator.cpp [1289:1376]
84 lines of code
9 McCabe index (conditional complexity)

void CHWTessellator::TriGenerateConnectivity( const PROCESSED_TESS_FACTORS_TRI& processedTessFactors )
{
    // Generate primitives for all the concentric rings, one side at a time for each ring
    static const int startRing = 1;
    int numRings = ((processedTessFactors.numPointsForInsideTessFactor+1) >> 1); // +1 is so even tess includes the center point, which we want to now
    const TESS_FACTOR_CONTEXT* outsideTessFactorCtx[TRI_EDGES] = {&processedTessFactors.outsideTessFactorCtx[Ueq0],
                                            &processedTessFactors.outsideTessFactorCtx[Veq0],
                                            &processedTessFactors.outsideTessFactorCtx[Weq0]};
    TESSELLATOR_PARITY outsideTessFactorParity[TRI_EDGES] = {processedTessFactors.outsideTessFactorParity[Ueq0],
                                            processedTessFactors.outsideTessFactorParity[Veq0],
                                            processedTessFactors.outsideTessFactorParity[Weq0]};
    int numPointsForOutsideEdge[TRI_EDGES] = {processedTessFactors.numPointsForOutsideEdge[Ueq0],
                                              processedTessFactors.numPointsForOutsideEdge[Veq0],
                                              processedTessFactors.numPointsForOutsideEdge[Weq0]};

    int insideEdgePointBaseOffset = processedTessFactors.insideEdgePointBaseOffset;
    int outsideEdgePointBaseOffset = 0;
    int edge;
    for(int ring = startRing; ring < numRings; ring++)
    {
        int numPointsForInsideEdge = processedTessFactors.numPointsForInsideTessFactor - 2*ring;
        int edge0InsidePointBaseOffset = insideEdgePointBaseOffset;
        int edge0OutsidePointBaseOffset = outsideEdgePointBaseOffset;
        for(edge = 0; edge < TRI_EDGES; edge++ )
        {
            int numTriangles = numPointsForInsideEdge + numPointsForOutsideEdge[edge] - 2;

            int insideBaseOffset;
            int outsideBaseOffset;
            if( edge == 2 )
            {
                m_IndexPatchContext.insidePointIndexDeltaToRealValue    = insideEdgePointBaseOffset;
                m_IndexPatchContext.insidePointIndexBadValue            = numPointsForInsideEdge - 1;
                m_IndexPatchContext.insidePointIndexReplacementValue    = edge0InsidePointBaseOffset;
                m_IndexPatchContext.outsidePointIndexPatchBase          = m_IndexPatchContext.insidePointIndexBadValue+1; // past inside patched index range
                m_IndexPatchContext.outsidePointIndexDeltaToRealValue   = outsideEdgePointBaseOffset 
                                                                            - m_IndexPatchContext.outsidePointIndexPatchBase;
                m_IndexPatchContext.outsidePointIndexBadValue           = m_IndexPatchContext.outsidePointIndexPatchBase
                                                                            + numPointsForOutsideEdge[edge] - 1;
                m_IndexPatchContext.outsidePointIndexReplacementValue   = edge0OutsidePointBaseOffset;
                SetUsingPatchedIndices(true);
                insideBaseOffset = 0;
                outsideBaseOffset = m_IndexPatchContext.outsidePointIndexPatchBase;
            }
            else
            {
                insideBaseOffset = insideEdgePointBaseOffset;
                outsideBaseOffset = outsideEdgePointBaseOffset;
            }
            if( ring == startRing )
            {
                StitchTransition(/*baseIndexOffset: */m_NumIndices, 
                               insideBaseOffset,processedTessFactors.insideTessFactorCtx.numHalfTessFactorPoints,processedTessFactors.insideTessFactorParity,
                               outsideBaseOffset,outsideTessFactorCtx[edge]->numHalfTessFactorPoints,outsideTessFactorParity[edge]);
            }
            else
            {
                StitchRegular(/*bTrapezoid*/true, DIAGONALS_MIRRORED,
                              /*baseIndexOffset: */m_NumIndices,
                              numPointsForInsideEdge,
                              insideBaseOffset,outsideBaseOffset);
            }
            if( 2 == edge )
            {
                SetUsingPatchedIndices(false);
            }
            m_NumIndices += numTriangles*3;
            outsideEdgePointBaseOffset += numPointsForOutsideEdge[edge] - 1;
            insideEdgePointBaseOffset += numPointsForInsideEdge - 1;
            numPointsForOutsideEdge[edge] = numPointsForInsideEdge;
        }
        if( startRing == ring )
        {
            for(edge = 0; edge < TRI_EDGES; edge++ )
            {
                outsideTessFactorCtx[edge] = &processedTessFactors.insideTessFactorCtx;
                outsideTessFactorParity[edge] = processedTessFactors.insideTessFactorParity;
            }
        }
    }
    if( Odd() )
    {
        // Triangulate center (a single triangle)
        DefineClockwiseTriangle(outsideEdgePointBaseOffset, outsideEdgePointBaseOffset+1, outsideEdgePointBaseOffset+2, 
                       m_NumIndices);
        m_NumIndices += 3;
    }
}