Development goals

I have attempted various isometric projects in the 12 years since I began programming but there was always a rather large stumbling block for me when trying to approach the problem; depth sorting. After spending the last month working on my latest isometric engine with several clearly defined goals I have decided to publish my experiences in this blog in the hope that someone (maybe even you!) will learn something from it and I can feel all nice inside when they (that's you) send me a nice email thanking me for enlightening them on a subject that in my experience has very little in the way of tutorials or reference material. My goals, for your dilectation are as follows:

• Objects can be anywhere within the play space (X,Y and Z)
• Objects can come in any size (Width, Height and Depth)
• Objects cannot intersect
• Objects will collide using bounding boxes
• All objects will be ordered correctly depending on position and size
  
• Tiling is not required though it is possible

I am writing the engine in Delphi (Pascal) but for the most part I will try to convey techniques using pseudo code and diagrams rather than platform specific code. I am already partway through the development process and as such a lot of the following techniques I have already coded and tested so the following posts will be used to illustrate my methods so far.