Bentley Systems, Inc.

Paul Connelly

Raymond B Bentley

Keith A Bentley

Casey Mullen

Shaun Sewall

In example embodiments, a proprietary implementation of tile-based and/or non-tile-based graphics processing is provided at run-time as a binary for use in an open-source infrastructure modeling platform. An open-source repository from which the infrastructure modeling platform is built includes a backend module and definitions of the interface of a visualization module from a private repository that implements the tile-based and/or non-tile-based processing. The open-source repository lacks code for the underlying implementation of the visualization module. The implementation of the visualization module is instead maintained in a private repository and built therefrom. In operation, the backend module calls an exposed function of a DLL that returns a pointer to a binary implementation of the visualization module. When graphics of an infrastructure model are required, the backend module utilizes the defined interface with the pointer to request tile-based and/or non-tile-based processing from the visualization module.

Techniques for providing proprietary tile-based and/or non-tile-based graphics processing to an open-source infrastructure modeling platform

In example embodiments, a proprietary implementation of solid modeling is provided at run-time as a binary to an open-source infrastructure modeling platform. The binary includes functionality of a solid modeling module that manipulates and uses BReps that represent geometry of elements of an infrastructure model. When an application that utilizes the open-source infrastructure modeling platform requires solid modeling, it may have a backend module call an exposed function of a DLL that returns a pointer to the binary. The backend module uses the pointer to create a session, which may be divided into a number of individual partitions that each correspond to one of its individual threads. BReps may be assigned to individual partitions. When a thread requires BReps to be manipulated and/or used, the corresponding partition may be used to acquire the needed BReps, perform the solid modeling operations, and either return results or an error.

Techniques for providing proprietary solid modeling to an open-source infrastructure modeling platform

In example embodiments, techniques are provided for visualizing a 3D model in an interactive editing workflow. A user modifies one or more elements of a model of the 3D model, by inserting one or more new elements having geometry, changing the geometry of one or more existing elements and/or deleting one or more existing elements having geometry. An updated view of the 3D model is then rendered to reflect the modification to the one or more elements in part by obtaining, for each new element or changed existing element of the model visible in the view, a polygon mesh that represents geometry of the individual element, obtaining a set of tiles that each include a polygon mesh that represent collective geometry of a set of elements intersecting the tile's volume, displaying the polygon mesh for each new element or changed existing element, and displaying the set of tiles while hiding any deleted or changed existing elements therein.

Hybrid tile-based and element-based visualization of 3D models in interactive editing workflows

In example embodiments, techniques are provided for refining tiles of an HLOD tree representing a model in order to display a view. A frontend module selects a tile represented by a node of the HLOD sub-tree and obtains information describing geometry of the selected tile. It determines that the selected tile requires refinement to support the view of the model based on the information describing geometry of the selected tile. A tile refinement strategy is determined from a plurality of tile refinement strategies. The frontend module applies the determined tile refinement strategy to the selected tile to generate one or more child tiles that have a higher resolution than the selected tile, the one or more child tiles represented by child nodes added to the HLOD sub-tree. The frontend module displays the view of the model at least in part by showing tiles represented by nodes of the HLOD sub-tree.

Efficient refinement of tiles of a HLOD tree

Visualization of massive 3D models in interactive editing workflows

In example embodiments, techniques are provided for decoupling user access to infrastructure models from proprietary software that maintains and updates the infrastructure models. A backend application may include an infrastructure modeling backend module that, among other functions, handles communication with an infrastructure modeling frontend module of a frontend application that provides user access to the infrastructure model, infrastructure modeling hub services that maintain repositories for the infrastructure model, and an infrastructure modeling native module that creates, performs operations upon, and updates local instances of a database that stores the infrastructure model. While the infrastructure modeling backend module may pass information obtained from the infrastructure modeling frontend module and infrastructure modeling hub services to the infrastructure modeling native module, it may be functionally separated from the software of the infrastructure modeling native module that understands how to maintain and update infrastructure models, including interacting with local instances of the database.

In various embodiments, techniques are provided for coordinating the assignment of codes to infrastructure elements in an infrastructure modeling software architecture. A chain of authority is provided from a code authority local to a client to a cloud-based code authority service. Further, a code is structured in three parts, including a code specification part identifying a code specification that indicates what information is encoded into the code and how it is encoded, a code scope part based on boundaries over which the code authority guarantees the code is unique, and a code value part with a unique value.

Techniques for coordinating codes for infrastructure modeling

In example embodiments, techniques are provided for converting geometry of an infrastructure model represented as high-level geometric primitives having a given symbology to low-level primitives, and encoding these low-level primitives into tile contents suited for transmission, and ultimately display upon, on a client device. An architectural split between frontend applications and backend applications may allow conversion of the high level primitives to be performed remote from the client devices by backend applications. Backend applications may be executed on robust hardware devices that execute software in a multi-threaded environment on powerful CPUs. By performing CPU-intensive operations on backend applications, frontend applications on client devices may be required to do little more than submit low-level primitives for rendering on their GPU.

Conversion of infrastructure model geometry to a tile format

In example embodiments, techniques are provided for frontend-driven, incremental HLOD sub-tree creation and dynamic generation of tiles. An infrastructure modeling frontend module (e.g., a iModel.js Frontend module) of a frontend application may incrementally create a local HLOD sub-tree, beginning with an initial HLOD sub-tree based on initial metadata provided without tile contents, and refined based on metadata provided with tile contents, from an infrastructure modeling backend module (e.g., a iModel.js Backend module) of a backend application. The local HLOD sub-tree of each infrastructure modeling frontend module may differ based on the individual tiles requested and the tile refinement strategies employed. The infrastructure modeling backend module may not maintain an HLOD tree, and simply generates tiles upon request, serving them and storing them in a tile cache incase they are needed again.

Growing community of inventors

Coatesville, PA, United States of America

Paul Connelly