It’s a moiré sample brought on by aliasing. In your examples, the Moiré patterns happen when a repetitive sample of excessive spatial frequency is sampled at low decision.

Consider the Wikipedia instance reference picture:

The bricks kind a repetitive sample. Because there’s many bricks, the ensuing texture has a excessive spatial frequency. Here’s the identical picture with a diminished decision:

Lowering the decision has lowered our pattern price to the purpose that an apparent moiré sample happens. Because there are fewer pixels, data has been misplaced. And as a result of the brick texture is not completely aligned to the pixel grid, the data is not misplaced evenly – some bricks lose extra crimson brick pixels than their neighbors & the equally for the white mortar pixels. This places the periodic spatial sign of the brickwork out of part. The threshold for this drawback is set by the Nyquist–Shannon sampling theorem.

Mipmapping can be utilized to cut back the artifacts on moiré inclined textures. But in your Minecraft instance, the ‘texture’ is successfully made throughout a number of blocks, so it will possibly’t be mitigated by mipmaps. Spatial anti-aliasing may assist, however solely to a degree as we’re restricted by the finite nature of the display screen. Generally talking, the aim is to get one thing that is ok via some mixture of graphics methods (to reduces the artifacts), artwork / texture selections (to keep away from error inclined visuals) and sport design (to make occurrences temporary &/or much less impactful).