Speaker
Description
In our contribution we describe a service that has been recently developed at IT4Innovations. The service specializes on image rendering and utilizes performance of an HPC cluster for this kind of task. The abbreviated name is R-a-a-S and the meaning is Rendering as a Service.
Probably all data that are processed on a computer sooner or later come to the fact that it is necessary to visually represent them. To obtain high visual quality of such outputs image rendering is employed. It synthetizes images from 2D or 3D models in a computer scene. Such task is handled by specialized software called renderer. To achieve photorealistic quality from synthetically generated scenes physically based renderers are used. We have used Cycles renderer from open-source Blender as a main starting point on the way to rendering service. We have modified Cycles core and created CyclesPhi to support efficient rendering on a cluster. It enables rendering on a classical CPU and also MIC accelerated nodes of a cluster.
To continue on the way of creating the rendering service it was necessary to build some sort of intermediate layer that converts user demands into computation tasks for a cluster. We have conveniently used HEAppE middleware that has been also developed at IT4Innovations. It manages and provides information about jobs on the cluster. It implements necessary job management tools together with the user authentication and provides appropriate feedback for the client. We have extended the HEAppE functionality by job arrays to better suit specific requirements typical for rendering jobs.
To complete the pipeline of the rendering service a client application that communicates with the middleware on one side and directly with the user on the other side was necessary. Decision was made to create the client directly in Blender. It is a popular and dynamically growing 3D open-source solution with a broad user base. Therefore, direct implementation of the client in Blender can deliver HPC rendering capability right at hands of a creator or a user of the 3D content. Our rendering client was created as a Blender addon and tested on main user platforms (Win/Mac/Linux). Our rendering service is ready and waiting for users.
