public void setEdgeColor(ColorRGBA edgeColor) {
        this.edgeColor = edgeColor;
        if (material != null) {
            material.setColor("EdgeColor", edgeColor);
        }
    }
Sets the edge color, default is black

@param edgeColor the desired color (alias created, default=(0,0,0,1))
jme3-effects/src/main/java/com/jme3/post/filters/CartoonEdgeFilter.java