generating 3-d plots

Dear all, I am working on obstacle aviodance algorithm. I am doing it through constraint optimisation techniques. I wish to formulate a x-y-z field where x and y is distance in meters and z is height. In this plane i wish to places various objects with different shapes (circle, oval, square etc.) representing the obstacles. Can someone suggest some generic single equation consisting of tuning parameters using which i can do it. I tried approch given in section 3.3 of http://www.sciencedirect.com/science/article/pii/S1000936113000915 but i was unable to show same results. Plesae help and suggest. regards