COMPUTATION AS A TOOL FOR COLOUR FACADE DESIGNSally SempleScott Chase

Department of Architecture

“And the hanging for the gate of the court was needlework, of blue and purple and scarlet and fine twined linen... ”

Exodus 38.16

Tobermory

Burano

Turin

Chateau-Double apartments (Lenclos)Chateau-Doble

Dulux paints

celebration

salsa melt 1

salsa melt 2

salsa melt 3

salsa melt 4

salsa melt 5

salsa melt 6

russian velvet

cuttlebone

jade cluster

Harmony

Identity Similarity Contrast

Moon & Spencer: Colour harmony rules

Variation in value Variation in saturation

Variation in hue

Pleasing intervalsIdentity from 0 to a just

noticeable difference

from 0 to a just noticeable difference

from 0 to a just noticeable difference

Similarity from 0.5 to 1.5 from 3 to 5 from 7 to 12 steps

Contrast from 2.5 to 10 7 or over from 28 to 50 steps

Displeasing intervals

1st ambiguity from a just noticeable difference to 0.5

from a just noticeable difference to 3

from a just noticeable difference to 7

2nd ambiguity from 1.5 to 2.5 from 5 to 7 from 12 to 28 steps

glare more than 10

RGB vs. Munsell systems

complexity of exterior colour

Example: Glasgow terrace

Adaptation of Moon & Spencer to Windows HSL

Variation in value only(0-255)

Variation in saturation only(0-255)

Variation in hue only(0-255)

Pleasing intervals

Identity from 0 to 5 from 0 to 10 from 0 to 5

Similarity from 12 to 40 from 50 to 90 from 18 to 30

Contrast over 60 over 120 from 70 to 128

Colour Combinations software

Two step process1. Generate the colour palette2. Generate the set of colour combinations

Parameters– Environmental colours– Undesirable hue ranges– Identity level– Similarity range– Contrast level– Step (granularity)

– Manually alter the values for saturation and value

Colour Combinations interface

Design for contrast: “Burano” palette

Design for integration: “Chateau-Double” palette

Design for harmony

Limitations

•Harmony definitions limited to hue•Excessive computation time for more than 50 hues

•High knowledge of colour harmony and systems needed to adjust variables and interpret results

•Conflict between Munsell and HSL colour systems produces distortions in harmonies

•Manual selection and development required to produce useable designs

Possible further development

•Input by colour rather than number•Output format to allow better assessment of scheme in

context•Allow a variety of facade forms rather than single example•Use different elements to establish context or provide

unifying colour•Fix specific colours within a scheme or limit specific elements

to their own palettes•Specify patterns or rhythms within a colour scheme•Allow variation in saturation and value•Address relative complexity of the design involving form and

area of design elements•Use a more perceptually accurate colour system than HSL