Inspired by the actual blooming of one of my orchids, Angraecum magdalenae, the flower was modeled (using splines and patches) and rendered in LightWave 3d
Although the image is two dimensional, the CGI technology used to generate it requires the creation of a three dimensional model of the flower on a computer. Think Toy Story, but in a single frame without the animation. A partially rendered image of the flower can be seen on this page.
I had thought that Prem Subrahmanyam's work was the only example of a rendered image of an orchid flower on the web, but see TurboSquid for a bunch of them!