Id)
                rootDf.childFrames[df.id] = df
            }
        }

        this.computeRenderData = function (df) {
            let result = []
            let pos = 0
            for (let col = 0; col < df.cols.length; col++) {
                if (df.cols[col].parent === undefined)
                    pos += this.computeRenderDataRec(df.cols, col, pos, 0, result, false, false)
            }
            for (let i = 0; i < result.length; i++) {
                let row = result[i]
                fo