[自定义图表]数据与坐标的相互转换

数值转坐标

/**
 * @return 数值到坐标的转换器
 */
public Function getCanvasY(int maxY, int minY, float maxValue, float minValue) {
    return value -> {
        float canvasDistance = maxY - minY;
        float valueDistance = maxValue - minValue;
        float scale = canvasDistance / valueDistance;
        return maxY - (value - minValue) * scale;
    };
}