One of major evolutions of the additive manufacturing is the ability to produce parts with functionally graded materials (FGM). However, manufacturing of these parts is limited to discrete or nearly continuous FGM on samples. To achieve this, it is necessary to have a global control of processes and to develop methodologies to help designers and manufacturers. A methodology to produce morphologically complex parts is proposed in this paper. It consists in classifying all typologies of bi-materials gradients with mathematical description. Each typology of gradient is associating with manufacturing strategies in order to choose slicing and path strategies. Afterwards, mathematical data are used to have a global control of a process. This paper presents the principle of this methodology and the mathematical models which are chosen to describe part and manufacturing.