This paper might be a pre-copy-editing or a post-print author-produced .pdf of an article accepted for publication. For the
definitive publisher-authenticated version, please refer directly to publishing house’s archive system.

Introduction
Aspects concerning the well-being of people in
both outdoor and indoor spaces are relevant in
trying to enhance the environmental quality of
urban spaces. In fact, the delicate relationship
existing between the assessment of the urban
fabric and the design of open spaces defines the
urban environmental quality and assesses the
success of a city. This careful balance inside the
urban form is surprisingly tangible in numerous
historical city centres, and was generated
through a long process of transformations over
time. Today, cities evolve rapidly and the slow
process of adaptation of urban shape to meet
human needs and sustain ecological diversity is
no longer feasible.
Why was the technique created?
The proposed set of tools is presented as an
alternative way to manage the complex set of
environmental variables in the frame of rapid
urban change. It allows us to investigate simul-
taneously different environmental aspects, such
as solar access, cross-ventilation, energy con-
sumption, etc., in relation to the arrangement
of the urban fabric. Algorithms defined in the
Matlab environment and derived from image-
processing can work with very simple raster
images of the urban texture stored in bitmap
format. Potential users might simply use the
proposed set of tools, or implement new
algorithms to meet their needs and compare
different design solutions from the environ-
mental and morphological viewpoints. In fact,
using this set of tools, a new paradigm for
assessing the environmental consequences
generated by the urban texture is investigated.
This is centred on the relationship existing
between environmental indicators and urban
morphology: the question is if – and in what
measure – the correct arrangement and the
shape of the urban fabric alone might improve
the environmental behaviour of the city. With
the aim of creating effective environmental
quality starting just from morphology, several
design tools can be developed, assessing new
potentialities related to the form of human
settlements. For instance, the energy-based
morphogenesis of the built environment could
be intended as the first step towards the
improvement of the sustainability of cities with
no additional cost due to the application of
complex technologies.
The technique revealed itself to be useful for
simulations on alternative design schemes over
large-scale masterplans and for extensive and
complex urban areas, helping to make decisions
supported by measured quantification. In parti-
cular, the technique demonstrates the potential
of digital urban models based on raster images
for the analysis of the city, which brings with it
many advantages such as fast computability,
flexibility, precision and comparability of results
obtained from several algorithms.
The tools were initially created to compare
the environmental behaviour of different urban
configurations. In fact, the technique might
be desirable in comparative studies, whereby
environmental indicators can be mapped and
1EEE
2
3
4EEE
5
6
7
8
9
10
1
2
3
4
5
6EEE
7
8EEE
9
20
1
2
3
4
5EEE
6
7
8
9
30
1
2
3
4
5
6
7
8
9
40
1
2
3
4
5
6
7
8
9
50EEE
14 Raster cities: image-processing
techniques for environmental
urban analysis
Eugenio Morello and Carlo Ratti
4993P URBAN SUST 09-20-A/rev/lb.qxd 1/10/07 16:26 Page 119