Arguments

styleId  (ename)  specifies the (Label or Symbol) style to query
orientation  (string)  one of the "Style Orientation" values (see Remarks)
partName  (string)  one of the 'Setting' strings returned by civil:style-get-displaysettings
parameter  (string)  one of the parameters returned by civil:style-get-displayparams
value  (integer|double|string|ename)  the new value to be assigned for the parameter

Return

T or NIL

Example

(vl-load-civil)  T
(setq points (civil:pgroup-get-allpoints "_All points"))
(<Entity name: 6c1e30c0> <Entity name: 6c1e2940> <Entity name: 6c1e2980> <Entity name: 6c1e2ac0> <Entity name: 6c1e2a00> <Entity name: 6c1e2b00> <Entity name: 6c1e2700> <Entity name: 6c1e2b40> <Entity name: 6c1e2b80> <Entity name: 6c1e2c40>)
(setq pointename (nth 2 points))  <Entity name: 6c1e2980>

(setq styleId (civil:point-get-symbolid pointename)) <Entity name: 32003d50>

(setq res (civil:style-get-displayparams styleId "Plan" "Symbol"))
(("Visible" . "On") ("Color" . 256) ("Layer" . "") ("Linetype" . "ByLayer") ("LTScale" . 1.0) ("Lineweight" . -3) ("PlotStyleType" . 1) ("PlotStyleId" . ""))

(civil:style-set-displayparam styleId "Plan" "Symbol" "Visible" "Off")  T

(setq res (civil:style-get-displayparams styleId "Plan" "Symbol"))

(("Visible" . "Off") ("Color" . 256) ("Layer" . "") ("Linetype" . "ByLayer") ("LTScale" . 1.0) ("Lineweight" . -3) ("PlotStyleType" . 1) ("PlotStyleId" . ""))

Remarks

orientation can be one of the "Plan" "Model" "Profile" "Section" strings;
partName is one of the 'Setting' strings returned by civil:style-get-displaysettings;
parameter is one of the parameters returned by civil:style-get-displayparams
supported Style objects : Label Style + Symbol Style for "Civil3D Point"; will be extended in future BricsCAD versions