A_QEM=0,/**< Approximates the geometry of an edge collapse by quadric error metric minimization [GH97]. */
A_MidEdge=1,/**< Approximates the geometry of an edge collapse by placing the resulting vertex in its middle. */
A_CornerCutting=2,
A_TangentPredict1=3,
A_TangentPredict2=4,
A_NormalArea=5,
A_NormalArea=5,/**< EXPERIMENTAL Approximates the geometry of an edge collapse by minimization of its normal times area measure [Sauvage] */
// Geometry + color approximators
A_ColorNaive=6,
A_ColorQEMext=7,
A_GeomColorOpt=8,
A_ColorNaive=6,/**< Approximates the color of the resulting vertex by linear interpolation (based on the approximated position) of its two predecessors. */
A_ColorQEMext=7,/**< Approximates both geometry and color of the resulting vertex by minimization of the extended (R^6) quadric error metric [GH98]. */
A_GeomColorOpt=8,/**< EXPERIMENTAL. */
// One approx per half-edge
// Generic (considers all provided attributes) approximator
A_hHalfCollapse=9,
A_hHalfCollapse=9,/**< Approximates all provided attributes of a half-edge collapse by keeping the attributes of the first of two vertices. */
// Geometry approximator
A_hQEM=10,
A_hQEM=10,/**< Approximates the geometry of a full-edge collapse by quadric error metric minimization [GH97]. Compatible version for half-edge selectors. */
S_MapOrder=0,/**< Prioritizes edges in topological order. Requires a geometry approximator. */
S_Random=1,/**< Prioritizes edges in random order. Requires a geometry approximator. */
// Geom criteria
S_EdgeLength=2,
S_QEM=3,
S_QEMml=4,
S_MinDetail=5,
S_Curvature=6,
S_NormalArea=7,
S_CurvatureTensor=8,
S_EdgeLength=2,/**< Prioritizes edges in increasing order of their lengths. Requires a geometry approximator. */
S_QEM=3,/**< Prioritizes by their quadric error metric (QEM) error [GH97]. Requires a geometry approximator. */
S_QEMml=4,/**< Prioritizes edges by their "memoryless" quadric error metric (QEM) error [Hop99]. Requires a geometry approximator. */
S_MinDetail=5,/**< Requires a geometry approximator. */
S_Curvature=6,/**< Requires a geometry approximator. */
S_NormalArea=7,/**< EXPERIMENTAL Prioritizes edges ranked by their normal times area measure [Sauvage]. Requires a geometry approximator. */
S_CurvatureTensor=8,/**< Requires a geometry approximator. */
// Geom + color criteria
S_ColorNaive=9,
S_QEMextColor=10,
S_GeomColOptGrad=11,
S_ColorNaive=9,/**< Prioritizes edges by a sum of the QEM measure on geometry and the L2 distance between RGB colors of both adjacent vertices. Requires a geometry approximator. Requires a color approximator. */
S_QEMextColor=10,/**< Prioritizes edges by the quadric error metric (QEM) error extended in R^6 (x,y,z,R,G,B) [GH98]. Requires a geometry approximator. Requires a color approximator. */
S_GeomColOptGrad=11,/**< EXPERIMENTAL. Requires a geometry approximator. Requires a color approximator. */
// HALF-EDGE selectors
// Geom criteria
S_hQEMml=12,
S_hQEMml=12,/**< Prioritizes half-edges according to the quadric error metric (QEM) of the considered collapse [Hop99]. Requires a geometry approximator. */
// Geom + color criteria
S_hQEMextColor=13,
S_hColorGradient=14,
S_hQEMextColor=13,/**< Prioritizes half-edges by the quadric error metric (QEM) error extended in R^6 (x,y,z,R,G,B) [GH98]. Requires a geometry approximator. Requires a color approximator. */
S_hColorGradient=14,/**< EXPERIMENTAL Prioritizes half-edges according to the sum of the quadric error metric (QEM) for geometry and the gradient color deviation metric of [Vanhoey,Sauvage]. Requires a geometry approximator. Requires a color approximator. */