Dennis Ippel, Developer in Bussum, Netherlands
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Dennis Ippel

Verified Expert  in Engineering

Augmented Reality (AR) Developer

Bussum, Netherlands
Toptal Member Since
May 26, 2014

A creative technology expert with 15+ years experience, Dennis has worked for over eight years for top ad agencies and production companies in London, UK. He makes high-end websites, digital installations and mobile apps, and he specializes in 3D, VR, and AR. He has worked for clients such as Nike, Ferrari, Fiat, Mini, EA, Disney, Unilever, and Intel, and he is the creator and lead developer of Rajawali, an open-source 3D framework for Android.


Cortina Productions
SteamVR, C#, Unity3D
HoloToolkit, Mixed Reality (MR), Photon Unity Networking (PUN), C#, Unity3D
Vuforia, Objective-C, iOS, JNI, Java, Android, C#, Unity3D




Preferred Environment

Unreal Engine 4, Unity, Xcode, Visual Studio, MacOS, Windows

The most amazing...

...project I've worked on is my open-source 3D framework, which I got to see grow and receive contributions from developers all over the world.

Work Experience

Unity3D Virtual Reality Developer

2018 - 2018
Cortina Productions
  • Created a virtual reality experience for the National Soccer Hall of Fame in the Toyota Stadium in Frisco, Texas. The physical installation consisted of four VR stations.
  • Used SteamVR with a HTC Vive headset.
  • Created custom physics for a shootout game.
  • Optimized and adjusted 3D motion capture animations.
Technologies: SteamVR, C#, Unity3D

Unity Photon Networking Engineer

2018 - 2018
  • Used Windows Mixed Reality with an Acer Mixed Reality headset.
  • Used Photon Unity Networking (PUN) for multi-player networking.
Technologies: HoloToolkit, Mixed Reality (MR), Photon Unity Networking (PUN), C#, Unity3D

Augmented Reality Developer

2017 - 2018
  • Built the foundation of an SDK and a proof of concept app using Unity3D.
  • Built a native plugin for Android using Java, C++, JNI.
  • Built a native plugin for iOS using Objective-C.
  • Used Vuforia for the Augmented Reality part.
Technologies: Vuforia, Objective-C, iOS, JNI, Java, Android, C#, Unity3D

Freelance Android Developer

2016 - 2017
Kontouré (via Toptal)
  • Built an Android prototype using OpenCV and Visage to explore the difference in performance.
  • Built an iOS app that was published to the app store.
  • Built a CMS using PHP, HTML and JavaScript.
  • Implemented Visage for face tracking.
  • Used SceneKit for 3D rendering.
Technologies: OpenCV, Visage, iOS, Android, Objective-C, Java

Unreal Engine 4/Kinect Developer

2016 - 2016
  • User detection and isolation using the Kinect SDK.
  • Created UE4 C++ blueprints for custom video capture.
  • Used Nvidia ShadowPlay for Video Capture.
Technologies: C++, Microsoft Kinect, Unreal Engine 4

Freelance Game Developer

2015 - 2016
Re:Creative Studios (via Toptal)
  • Implemented online multiplayer gaming for their “Ultimate Cornhole 3D” game.
  • Used Unity3D with C#.
  • Used PlayFab and Photon for online multiplayer gaming.
  • Helped them build a new game called “Ultimate Horseshoes”.
Technologies: PlayFab, Photon, C#, Unity3D

Co-founder, Developer, Designer, 3D modeler, Animator

2015 - 2015
Dara Technologies
  • Developed an augmented reality children's book concept.
  • Built an interactive AR demo in Unity3D.
  • Created 3D models in Blender.
  • Rigged and animated 3D models.
  • Built and designed the company website and campaign page.
Technologies: CSS, JavaScript, HTML, Blender, Vuforia, Unity3D

Senior Android Developer

2015 - 2015
  • Created a video recording and processing app for the X-Factor TV show.
Technologies: Java, Android

Virtual Reality Developer

2015 - 2015
  • Built a virtual reality tour through one of the world's most famous music studios.
Technologies: GLSL, OpenGL ES, Java, Google Cardboard, Rajawali

WebGL Developer

2015 - 2015
  • Built a WebGL prototype for one of the world's biggest tech companies.
Technologies: JavaScript, WebGL

Augmented Reality Developer

2015 - 2015
  • Built an augmented reality app using Vuforia AR SDK, Rajawali 3D Framework and 4D Views animations (real-time generated textured meshes acquired from multi-camera video).
Technologies: 4D, Blender, Java, Rajawali, Vuforia, Android

Unity3D Developer

2014 - 2015
  • Built an animation editor using Unity3D and Mixamo animations.
Technologies: C#, Mixamo, Blender, Unity3D

Freelance Augmented Reality Developer

2014 - 2014
Medikidz (via Toptal)
  • Built a cross-platform app using Unity3D and C#.
  • Used Vuforia for Augmented Reality.
  • Built an app to teach children about various diseases and types of medicine.
Technologies: C#, Vuforia, Unity3D

Senior Android Developer

2014 - 2014
  • Created a video recording and processing app for the X-Factor TV show.
Technologies: Java, Android

Competency Lead

2013 - 2014
  • Curated “The Room,” a space that showcases new technologies applied in a meaningful way.
  • Found new ways to help the creative research and development (CR&D) team learn and develop.
  • Helped educate the agency around the things that CR&D do, and kept evolving the craft of creative development within the team and the agency.
  • Developed rich, interactive experiences, mobile applications and interactive installations, for clients including Nike, Vodafone, Nissan, and Unilever.
  • Performed rapid prototyping for proofs of concept and pitches.
Technologies: Vuforia, Microsoft Kinect, OpenCV, C++, C#, Java, Node.js, JavaScript, WebGL, Unity

Senior Creative Developer

2009 - 2013
  • Developed rich interactive experiences, mobile applications, games, and interactive installations for clients, including Nike, Ferrari, Orange, Heineken, and EA.
  • Performed rapid prototyping for proofs of concept and pitches.
  • Configured continuous integration and build tools.
Technologies: Vuforia, Microsoft Kinect, OpenCV, C++, C#, Unity, Java, JavaScript, WebGL, Flex, Flash

Senior Creative Technologist

2009 - 2009
Agency Republic
  • Architected and built rich internet applications using Flex & Flash for clients including O2 and Jose Cuervo.
  • Worked as project lead and mentor.
Technologies: RobotLegs, Flash

Senior Creative Developer

2007 - 2009
  • Architected and built rich internet applications using Flex & Flash for clients including Nike, Yell, Johnnie Walker, Fiat, and Orange.
  • Worked as project lead and mentor.
  • Built mini games using Papervision3D.
  • Created and optimized 3D assets for games and websites.
Technologies: Remoting, PureMVC, Flex, Flash

Web Developer

2006 - 2007
Evident Interactive
  • Developed sites and banners.
  • Architected and built rich internet applications.
  • Built semantic, W3C compliant websites.
  • Worked as mentor and trainer.
  • Advised the management and sales teams about new technologies.
Technologies: CSS, Flex, Flash, JavaScript, XHTML

Java Developer

2005 - 2005
Atos Origin
  • Developed J2EE business applications for financial companies like Delta Lloyd and PricewaterhouseCoopers.
  • Created accessible user interfaces using XHTML, JavaScript, and CSS.
Technologies: CSS, JavaScript, XHTML, Java

Web Developer

2001 - 2005
Euro RSCG 4D
  • Developed and maintained Intel’s European e-Business sites.
  • Built back-end solutions for web applications.
  • Created web interfaces.
  • Mentored junior developers.
Technologies: Java, XML, CSS, JavaScript, HTML

Kontoure Virtual Makeup App

"Welcome to a new world of beauty. Get started by choosing from 4 easy to follow, step by step tutorials that every gal should master. You are going to look beautiful! We'll use augmented reality to carefully guide you through each step, showing you exactly how and what to do. Take your time and follow along. Shop additional pattern tutorials. We're adding new full looks, face, eye and lip looks all the time. You will find distinct makeup tutorials to match your style."

Kontoure is an Ohio, US-based startup specializing in beauty tech. I built an Android prototype for them to explore various face tracking APIs, an iOS app that was published to the App Store, and a web-based CMS. The app uses augmented reality as an instructive aid for makeup application.

PlusOne SmartTutor
Smart Tutor is an intelligent, immersive learning platform developed with artificial intelligence (AI) and mixed reality (MR) technologies. Smart Tutor empowers users to improve social interaction and communication skills through focused, immersive practice with real-time feedback.

I took care of the multi-player networking part that enabled virtual class and conference rooms. Technologies used were Unity and Photon.

National Soccer Hall of Fame Virtual Reality Experience
The NSHOF Experience is be an 19,350-square foot segment of the NSHOF that honors the past while fully incorporating modern technology of the present and future including virtual reality, gesture technology, and interactive digital video boards throughout to celebrate the players, veterans, and builders of American soccer that have elevated the sport to where it is today.

I was responsible for a virtual reality experience that centered around two legendary goalkeepers that played for team USA: Tim Howard and Briana Scurry. The experience lets you make their historic saves and you can also compete with other visitors in a virtual shoot-out. Built with Unity, HTC Vive, and SteamVR.

ARKit Work

In 2017, I first used ARKit to display converted, optimized 3D models that were downloaded at runtime from a server into an iOS app.

When Apple announced the USDZ file format, I came up with a server-side solution to convert many other 3D file formats to USDZ.

More recently, I focused on content creation and workflow optimization. Getting animated 3D content from Blender into XCode/SceneKit is not as straightforward as it should be. This exercise helped me to come up with solutions to streamline this workflow.

John Lewis - Buster's Garden

"John Lewis' Oxford Street flaghip store has dressed its shop windows for the festive season along the theme of Buster's tale, and are making passers-by stop, smile and take a few snaps.

This year, however, John Lewis has added an extra element to the fun with a virtual reality zone where you can experience being right in the middle of Buster's garden.

Using a headset, you step on a real trampoline and have the chance to pet foxes and honey badgers as they come along for a bounce."

I took care of inserting the user into a take away video using a Kinect. The user is detected and isolated from the background and merged into the virtual surroundings. The video is then uploaded and a share link is generated and printed out.

X Factor FX Star

FX Star allows users to create their own music videos, lip-syncing along to their favorite tracks, and adding a splash of glamour or comedy to their performances with fun filters such as Apple Head, Teddy Boys, Party Paint, Comic Book, Solar System, Glam Rock, or Flower Power.

The app launched in the App Store and Google Play with three tracks: Zara Larsson’s "Lush Life," Sigala’s "Give Me Your Love," and Birdy’s "Wild Horses."

The best videos to be submitted by the general public each week will then be selected to air on TV during The X Factor ad breaks.

I wrote native Android and iOS plugins for Unity3D for video capturing and processing.

Dara - The Time Tub Twins
Dara Technologies develops books that enable children to interact with stories in ways never before imagined. Thanks to their app, children become the storytellers of their own adventure by interacting with 3D characters that appear on its pages.

At several points in the book, decisions can be made that influence the story, unlocking different adventures in the app. For example, you can choose what era you visit, what inventions you make, or what objects you take with you on your journey. All these decisions are made by interacting with the animated 3D characters and objects that magically pop out of the pages of the book when you hover your mobile device over its pages.

We modeled the 3D characters, rigged them, animated them, and built the augmented reality app for iOS and Android.

Nissan IDx Virtual Reality

Nissan IDx is a virtual reality experience that brings the concept of Nissan co-creating cars with a younger audience to life. This is the first 3D experience for a global brand to debut the Oculus Rift HD.

Rajawali is an open-source 3D framework for Android, based on OpenGL ES 2.0. It can be used for normal apps as well as live wallpapers.

Nike: British 10K Run
25,000 runners make it count in London. Powered by Nike+, runners hit the streets of London for the most interactive British 10K the city has ever seen.

EA: FIFA 12 Scarf
Users could get their Twitter message on the world’s longest fan scarf. They had the chance to have it knitted for real into a meter of world-record-breaking scarf. I created the 3D version of this using Flash, ActionScript, and Pixel Bender. The project was quite challenging because of the limitation of these technologies. I managed to get it highly optimized using a variety of optimization techniques.

Speaking at International Conferences & User Groups

• Bilkent Mobile Days, Ankara, Turkey, Mobile Augmented Reality, 04/2014
• AnDevCon, San Francisco, USA, Rajawali: Easy 3D for Android, 11/2013
• AnDevCon, San Francisco, USA, Workshop: Augmented Reality + 3D: The Easy Way, 11/2013
• DroidCon, London, United Kingdom, 3D on Android: Open Source Workflow, 10/2013
• Android Developer Days, Ankara, Turkey, Running Amok with Rajawali for Android, 06/2013
• LFPUG, London, United Kingdom, Running Amok with Rajawali for Android, 03/2012
• FITC, Toronto, Canada, Exploring the Kinect, 05/2011
• FFK11, Cologne, Germany, Exploring the Kinect, 04/2011
• LFPUG, London, United Kingdom, Exploring the Kinect, 03/2011
• gotoAndSki(), Stechelberg, Switzerland, Exploring the Kinect, 01/2011
• Siggraph, Los Angeles, USA, WebGL in an Ad Agency, 08/2010
• LFPUG, London, United Kingdom, Flash 3D Workflow, 01/2010
• Fronteers, Utrecht, The Netherlands, The HTML5 Element, 10/2007

OpenGL ES 1.1 -based 3D framework for Android. I mainly focused on file importers and animation. Part of a team of two developers.

Blender WebGL Exporter
Python exporter script. Creates JavaScript files that contain 3D object geometry that can be dynamically loaded using JSON.

Blender ActionScript Exporter

Python exporter script. Creates ActionScript classes containing 3D object geometry that can be embedded in Flash projects.


3D Engine for Flash using ActionScript 3.0. Developed 3D file importers and created, designed, and modeled demos as a part of a team of developers.
2001 - 2005

Bachelor's Degree in Software Engineering

Leidse Onderwijs Instellingen - Leiderdop, The Netherlands


OpenGL ES, Three.js, WebGL, jQuery, Intel Perceptual Computing SDK, OpenCV, Node.js


Blender, Affinity Photo, Adobe Illustrator, Sublime Text, Microsoft Visual Studio, Adobe Photoshop, Flash, Mixamo, Visual Studio, Xcode, PlayFab, MeshLab, Inkscape


Unity, Rajawali, Unity3D, Microsoft Kinect, iTween, Unreal Engine 4, iOS SceneKit, ARKit, OGRE, OpenNI, Flex, RobotLegs, PureMVC, Photon, JNI, Photon Unity Networking (PUN)


HTML5, Java, JavaScript, C#, Flash ActionScript, Python, XHTML, CSS, HTML, XML, GLSL, PHP, Swift, Objective-C, C++


Model View Controller (MVC), Object-oriented Programming (OOP), Prototype-based OOP, Agile Software Development, Cross-platform, Test-driven Development (TDD)


Vuforia, Windows, Android, MacOS, Oculus Rift, iOS, SteamVR


MySQL, MongoDB, Microsoft SQL Server


Augmented Reality (AR), Ajax, Extended Reality (XR), Mixed Reality (MR), Virtual Reality (VR), Unity Shaders, Leap Motion, Mesh Optimization, Remoting, 4D, Google Cardboard, Visage, HoloToolkit, 3D Modeling, 3D Animation, 3D

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