A method which extends the use of the cylindrical projection tool for the assessment of sunshine was developed. This method is a computer-based mathematical analysis using trigonometric functions. It enables to project building components and sun's position in the sky on a two-dimensional cylindrical projection chart for a wide range of simple and complex plane shapes, namely; inclined and non inclined vertical planes, segment of circular planes, semi-circular planes and circular planes. In this method, cylindrical projection will be more handled and manageable and will give more sensitive results. It uses Matlab programming language and its graphical potentialities. It will provide to designers and architects a quick and reasonable assessment of sunshine availability for complex building configurations at any time on any date of a given locality and consequently saving time and achieving a successful project. However, this projection method, may exhibit some limitations of its use in low latitudes (<20 degrees) if the sun is high in the sky. (C) 2012 Elsevier Ltd. All rights reserved.