Game developers can't always find their algorithms in an algorithms textbook. Academic algorithms tend to be general purpose and often aren't the best choice for games. For example, compare textbook image scaling algorithms to hq4x. Hq4x is very impressive! How could the textbooks have missed it? It's because it's not general purpose. It is designed to work on hand-drawn low-color sprite graphics in games, whereas the textbook algorithms work on all sorts of images. Another example is path-finding algorithms. Dijkstra's algorithm is a general-purpose algorithm; A* came out of AI research (which is slightly closer to game programming) and is a little more specialized. But there are plenty of techniques used in games that aren't found in the textbooks. They take advantage of game-specific knowledge: the structure of maps, the characteristics of moving units, etc.
The general purpose algorithms are a good place to start but don't limit yourself to them. There might be a specialized algorithm that works better for your problem, or it may be worth the effort to design your own algorithm.