With the introduction of physics-based algorithms and modeling environments, design processes have been shifting from the representation of materiality to the simulation of approximate material descriptions. Such computational processes are based upon enacting physical and material behavior, such as gravity, drag, tension, bending, and inflation, within a generative modeling environment. What is often lacking from this strategy is an overall understanding of computational design, that information of increasing value and precision is generated through the development and iterative execution of specific principles and integrative mechanisms. The value of a physics-based modeling method as an information engine is often overlooked, though, as they are primarily utilized for developing representational diagrams or static geometry inevitably translated to function outside of the physical bounds and parameters defined with the modeling process. The definition of computational design provides a link between process and a larger approach towards architecture an integrative behavior-based process which develops dynamic specific architectural systems interrelated in their material, spatial, and environmental nature. This paper, focusing on material integration, describes the relation of a computational design approach and the technical framework for a behavior-based integrative process. The application is in the development of complex tension-active architectural systems. The material behavior of tensile meshes and surfaces is integrated and algorithmically calibrated to allow for complex geometries to be materialized as physical systems. Ultimately, this research proposes a computational structure by which material and other sorts of spatial or structural behaviors can be activated within a generative design environment.