At the same time, the rendering portion of the game engine operated primarily with bitmaps and sprites. Today, game artists construct elaborate 3D scenes and characters. Often most of animation is implemented at the 3D engine level. Such animation typically obeys the laws of physics for realistic falling, bouncing, sliding, crashing, and so on. Most manual animation has been eliminated.
Artists now focus on details of character personalities and overall virtual world design.
This is a tremendous success of technology. Large 3D worlds and complex models produce floods of rectangles, polygons, textures and transformations. The ever-increasing number of operations is routed to hardware that grows more and more powerful to meet the computational demand. Modern 3D graphics software is probably less optimized than vintage 2D software. An optimized game only performs the necessary operations and the same commands are not executed redundantly.