flaws of painter's algorithm led to the development of Z-buffer techniques, which can be viewed as a development of the painter's algorithm by resolving depth conflicts on a pixel-by-pixel basis, reducing the need for a depth-based rendering order. Even in such systems, a variant of the painter's algorithm is sometimes employed. As Z-buffer implementations generally rely on fixed-precision depth-buffer registers implemented in hardware, there is scope for visibility problems due to rounding error. These are overlaps or gaps at joints between polygons. To avoid this, some graphics engines implement "over-rendering", drawing the affected edges of both polygons in the order given by the painter's algorithm. This means that some pixels are actually drawn twice (as in the full painter's algorithm), but this happens on only small parts of the image and has a negligible performance effect. References External links Painter's & Z-Buffer Algorithms and Polygon Rendering https://www.clear.rice.edu/comp360/lectures/old/HiddenSurfText.pdf https://www.cs.princeton.edu/courses/archive/spring01/cs598b/papers/greene93.pdf 3D computer graphics Computer graphics algorithms