Markus Hendrik Overmars (Dutch pronunciation: [ˈmɑrkɵs ˈɦɛndrɪk ˈmɑrk ˈoːvərˌmɑrs]; born 29 September 1958 in Zeist, Netherlands) is a Dutch computer scientist and teacher of game programming known for his game development application Game Maker. Game Maker lets people create computer games using a drag-and-drop interface. He is the former head of the Center for Geometry, Imaging, and Virtual Environments at Utrecht University, in the Netherlands. This research center concentrates on computational geometry and its application in areas like computer graphics, robotics, geographic information systems, imaging, multimedia, virtual environments, and games. Overmars received his Ph.D. in 1983 from Utrecht University under the supervision of Jan van Leeuwen, and has since been a member of the faculty of the same university. Overmars has published over 100 journal papers, largely on computational geometry, and is the co-author of several books including a widely used computational geometry text. Overmars has also worked in robotics. He was the first to develop the probabilistic roadmap method in 1992, which was later independently discovered by Kavraki and Latombe in 1994. Their joint paper, Probabilistic roadmaps for path planning in high-dimensional configuration spaces, is considered one of the most influential studies in motion planning, and has been widely cited (more than 2500 times as of 2014 according to Google Scholar). In 2011, Overmars and game designer Jochem Schut developed a snake video game called Super Snake HD as a mobile app; it was published by YoYo Games. Overmars founded and is CTO of Tingly Games in 2012. Tingly focuses on HTML5 games and e-cards / casual games, the latter of which is called "greeting games". He is also the original author of the XForms toolkit.