The Samaneh Hooshmand Modiriat Shahri Shahriyar is an environment for viewing and analysing a 3D city model that supports urban decisions grounded in geometric and spatial data. Its rendering engine is built on CesiumJS and presents the 3D city model in the browser. Measurement tools for distance, area, volume and elevation profile let the user extract the geometric properties of features from the model. Building simulation and shadow analysis are also available in the same environment for preliminary studies. The server layer is implemented with Express and PostgreSQL, and the system includes user authentication and an admin panel.
The problem this system solves
Urban management deals with decisions that depend on understanding space in three dimensions; two-dimensional maps alone are not enough for studies such as building height, views and the effect of shadows.
By presenting a 3D city model with geometric analysis tools, the system supports a preliminary examination of scenarios before a decision is made.
Having the model display, measurement and analysis in a single environment reduces movement between disparate tools.
The 3D city model on CesiumJS
The 3D model is rendered with CesiumJS, which allows smooth navigation of the model over the globe and combination with spatial layers.
Building and urban-feature models are shown in the scene as 3D geometry, and the user can control the view angle, rotation and zoom.
Combining the 3D model with descriptive data makes it possible to examine each feature in the context of the city.
- 3D navigation of the city model with view-angle and zoom control.
- Display of building and urban-feature geometry in the scene.
- Linking model features to their descriptive information.
Measuring distance, area, volume and profile
The distance tool computes the length of a path between chosen points on the model and is used for studies such as access distance or the length of a proposed route.
The area tool computes the extent of a boundary or surface from the model, and the volume tool estimates the capacity of a 3D volume such as an excavation or a construction volume.
The profile tool produces an elevation section along a path and presents it as an elevation profile chart, so the slope and level difference of the route can be examined.
Measurement outputs complement expert review and serve as the basis for a preliminary estimate.
Building simulation and shadow analysis
Building simulation allows the effect of a proposed volume to be examined within the existing city model and helps the user understand its impact before execution.
Shadow analysis examines the shading effect of features and buildings under different conditions and is used for the preliminary assessment of sunlight and shadow in a given area.
These analyses are decision-support tools and do not replace detailed specialist studies in fields such as urban planning or architecture.
Users, authentication and the admin panel
The system includes user authentication so that access to the model and the analysis tools is limited to authorised users.
The admin panel allows users to be defined and managed and their access level to be controlled.
- Urban specialist, who navigates the model and performs measurements.
- Analysis specialist, who studies shadows and building simulation.
- System administrator, who manages users and access levels.
Base data, deployment and integration
The server layer is implemented with Express and PostgreSQL, and spatial and descriptive data are held in the same environment.
The 3D model and spatial layers form the base data of the system, and the quality of the input model directly affects the accuracy of measurement and analysis.
The system can be deployed on the organisation’s server, keeping the data under the operator’s control.
Rollout and delivery
Rollout begins with preparing and loading the 3D model and the spatial layers of the target area.
Users and access levels are then defined in the admin panel, and the system is prepared for the specialists to use.
Afterwards the model and layers are updated on the basis of fresh data so that the presented picture stays consistent with the city.
Summary
The Samaneh Hooshmand Modiriat Shahri Shahriyar brings the 3D city model together with measurement tools, building simulation and shadow analysis in one environment and simplifies the geometric study of space.
Its implementation on CesiumJS for display and Express with PostgreSQL on the server gives the system a maintainable structure.
User authentication and the admin panel control access to the model and tools and make organisational use of the system feasible.