struct PK_blend_properties_s
    {
    PK_blend_propagate_t    propagate;     --- whether to progagate
                                           --- (PK_blend_propagate_no_c)
    PK_blend_vary_t         vary;          --- form of variation
                                           --- (PK_blend_vary_smooth_c)
    PK_blend_render_rib_t   render_rib;    --- enable renering of ribs
                                           --- (PK_blend_render_rib_no_c)
    PK_LOGICAL_t            draw_fix;      --- whether blend will be drawn
                                           --- and fixed (PK_LOGICAL_true)
    PK_blend_ov_smooth_t    ov_smooth;     --- enable smooth overflow
                                           --- (PK_blend_ov_smooth_diff_c)
    PK_blend_ov_cliff_t     ov_cliff;      --- enable cliff edge overflow
                                           --- (PK_blend_ov_cliff_diff_c)
    PK_blend_ov_cliff_end_t ov_cliff_end;  --- enable cliff edge end overflow
                                           --- (PK_blend_ov_cliff_end_no_c)
    PK_blend_ov_notch_t     ov_notch;      --- enable notch overflow
                                           --- (PK_blend_ov_notch_yes_c)
    double                  tolerance;     --- tolerance for blended edge
                                           --- (1.0e-5)
    double                  ribspace;      --- approx separation of rib lines
                                           --- (0.0)
    };
typedef struct PK_blend_properties_s PK_blend_properties_t;



This structure records a set of blend properties.