The case study focuses on design of the Singapore National Stadium roof and its architectural and structural constraints. The dialog between performance form generation and aesthetics was challenged through several design iterations and is critically reviewed in this paper. The collaboration of engineers and architects gave a form to this significant building that was slightly changed several times due to various conditions. The complex shape of the dome structure was resolved in one parametric model that could react on aesthetical and structural requirements. The landmark roof structure generated in computer had to be evaluated by designers and presented to decision making bodies.