Post
Creating a convincing depth illusion on flat surfaces by shifting texture coordinates based on viewing angle.
Parallax mapping takes normal mapping a step further by offsetting texture coordinates based on a height map and the camera's viewing angle. When you look at a parallax-mapped surface from an angle, the texture appears to shift in a way that creates a convincing illusion of depth, making bricks look like they have actual gaps between them and cobblestones look like they genuinely protrude from the ground. Parallax occlusion mapping adds self-shadowing within the texture, further enhancing the depth effect. The result is much more convincing than normal mapping alone, at a fraction of the cost of actual geometric detail from tessellation.
Example
The Elder Scrolls V: Skyrim's Special Edition uses parallax mapping on its stone walls and cobblestone paths, and modders have expanded it further with custom height maps that make dungeon walls look carved and weathered. Dark Souls III applies parallax techniques to many of its castle and cathedral surfaces, adding depth to brick and stonework. Star Citizen uses parallax occlusion mapping extensively on space station interiors and planetary surfaces to maximize visual detail without exploding polygon counts.
Why it matters
Parallax mapping sits in the sweet spot between normal mapping and tessellation, offering significantly more convincing depth than the former at significantly less cost than the latter. It is the go-to technique for adding visual depth to walls, floors, and other large surfaces where actual geometry would be prohibitively expensive but flat textures look unconvincing.
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