Guangzhou Tower AR Show
A National Day-themed mobile AR experience around Canton Tower, engineered as a WeChat Mini-Program with EasyAR Mega location-based SLAM. Promoted at the highest level of city leadership and built to handle launch-night concurrency in the six figures.
- Role
- Solo Developer
- Client
- Guangzhou Government, China
- Agency
- Chance 3D
- Year
- 2024
Stack
- AR
- WeChat Mini-Program
- EasyAR Mega
- SLAM
- Location-based
The brief
Guangzhou wanted citizens to point a phone at Canton Tower on National Day and watch a five-chapter story unfold against it. Chance 3D directed the concept, narrative, and visual design. I was sole technical contractor: field capture, mapping, mini-program runtime, AR rendering, and the infrastructure that had to survive launch night.
Why WeChat made this hard
Landmark AR in a WeChat Mini-Program fights the platform. WeChat does not expose the WebGL and SLAM hooks that browser AR runtimes depend on, so the standard approach was unavailable to me. I built on EasyAR Mega's location-based visual positioning, gated by GPS, rendering through the mini-program's own layer.
The obvious alternative was a native app, which most outdoor landmark AR at this scale uses. I did not take it. A native app puts an install between a curious citizen standing at the foot of the tower and the experience, and on a National Day evening almost nobody clears that bar. A mini-program opens with one tap. Accepting a harder engineering path to remove the install wall is the decision the whole project rested on.
Mapping a 600-metre tower
I captured on site, built the EasyAR Mega map, then went back repeatedly to test whether localisation held under different lighting, weather, and crowd conditions.
A landmark this size punishes assumptions. Visitors stand at wildly different distances and angles, the tower's own lighting changes through the evening, and by launch night bodies block much of what the positioning system wants to see. There is no way to validate that from a desk, only rounds of on-site ground-truth testing.
Building for launch night
National Day evening gives you one attempt in front of hundreds of thousands of people and the city's senior leadership at the same time. A backend problem is not a bug report, it is a public event.
I planned for network saturation rather than hoping to avoid it. Aggressive asset compression, CDN-fronted delivery, chapter assets streamed and tuned for mobile data, and degradation paths that keep the experience running when the network around the tower falls over.
Launch-night concurrency landed in the six figures across sessions and interactions by WeChat and EasyAR back-office figures. Guangzhou's Municipal Party Secretary promoted the activation publicly.