The chief executive of 3-D modeling software maker Caligari said in a blog post that his company has been acquired by Microsoft.

"I am pleased to announce that Caligari Corp. has become a wholly owned subsidiary of Microsoft Corporation," wrote Roman Ormandy, in an entry dated Thursday.

Ormandy said Caligari's imaging technology would be used to bolster Microsoft's Virtual Earth project, a platform on which businesses can create interactive, geographic maps overlaid with additional data.

"I am deeply convinced that the union of Caligari Technologies and the scope of Virtual Earth project and vision behind it creates the perfect home for us," Ormandy wrote.

A Microsoft representative was not immediately able to confirm the information. Caligari officials could not immediately be reached for comment.

Mountain View, Calif.-based Caligari is best known for its TrueSpace 3-D modeling software, which has been on the market for more than 20 years. The software lets animators, game designers, and other graphics professionals create three-dimensional renderings and special effects for a range of applications.

The most recent version, TrueSpace 7.5, includes a human character editor that allows users to create lifelike anatomical models with realistic joint and skeletal movements.

Caligari also operates TruePlace -- a Second Life type of online world that features a navigable, 3-D environment.

Microsoft in recent months has shown an uncharacteristic acquisitiveness. In addition to its headline-making $44.6 billion offer to buy Yahoo last week, the company last year picked up digital advertising agency aQuantive for $6 billion.

Also last year, Microsoft bought out automated voice services provider Tellme Networks for an undisclosed sum.