Other practical tool used
1. Literature and Historical transformation mapping tool
Historical maps and the writing documents in various periods can be abstracted, transferred and represented into the urban-space system. From the historic maps, the mountains, water, space form, streets, walls, official palace, context and facilities can be traced. In Xijin Dynasty, Geographer Pei Xiu (224-271) proposed “Six Criteria of Cartography”, including ratio, direction, distance, terrain, angle, camber. Based on a comparative perspective and literature records, the linguistics in ancient times can be applied into the modern graphic (Dong, 2009).
There is another analytical method to identify the fabric physical features based on the statistic analysis of a number of blocks in particular morphological regions in each period. Through the identification of the synchronic types of blocks, plots and building fabric in various parts, taking the example of XWC, the later intervention can have a more detailed guide. The space categories are defined by several criteria, including size, height, location, proportion, density, volume of physical forms and their relationship with the surrounding environment, such as orientation and connection with access routes.
2. Typo-morphology based analysis approach
Dated back to 1960s, morphology was firstly developed by European geographers in morphogenetic research. Until now, the framework of morphology can be classified into four areas: town plan, building form, land use and furthermore, morphological region, referring to the structure relationship between various urban units (Conzen, 1969) . Until 1990s, typo-morphology emerged firstly as Korpf introduced typology into the morphology to search for the intellectual differences and similarities of morphology models.
Firstly, historic center is divided into different tissues, and several sub-districts according to avenues and vital blocks’ evolution, caring for keeping correspondence with maps, Then to establish raw space bulks based on various dimension. By coding and synthetic method, the bulk can be fit in detail with some known porches, overhangs, roofs, windows, decorative materials. (Jia, 2014)
Aim to fulfill the historic morphology and maintain historic feature, the intervention, especially with new insertions, cares for original space form and allocate new functions need consistent with the old fabric. Besides the macro-level morphology analysis, the plan makes detailed intervention proposals for the buildings to preserve. New constructions and functions were inserted in some urban void with careful constraints with regard to some acceptable types, consistent with the surrounding urban landscape. In both cases, study to typology is applied in the conservation and rebuilding.