public void setEdgesThickness(int edgesThickness) {
        this.edgesThickness = Math.max(1, Math.min(edgesThickness, 10));
        this.edgesThickness *= 0.1f;
        postshadowMat.setFloat("PCFEdge", this.edgesThickness);
    }
Sets the shadow edges thickness. Default is 10. Setting it to lower values
can help reduce the jagged effect of shadow edges.

@param edgesThickness the desired thickness (in tenths of a pixel, default=10)
jme3-core/src/main/java/com/jme3/shadow/AbstractShadowRenderer.java