1. A method of adapting a computer program configured to use a raster-based application programming interface (API) for use with a ray tracing rendering technique, the method comprising: receiving from the computer program object data representative of objects to be placed in a scene via a plurality of API calls to the raster-based API; processing the object data in a raster-based streaming geometry frontend associated with the raster-based API to generate a stream of primitives for the scene; using a dynamic accelerated data structure generator including a plurality of parallel threads of execution to dynamically generate an accelerated data structure from the stream of primitives, wherein the accelerated data structure partitions the scene into a plurality of bounding volumes and arranges primitives from the stream of primitives within the plurality of bounding volumes; and with a ray tracing backend, accessing the accelerated data structure to determine whether any primitives are arranged within a bounding volume in the scene through which a ray is being projected and rendering image data for the scene using the accelerated data structure.