Bilinear filtering
Smooths magnified textures by taking a weighted average of the four nearest texels.
When a textured surface is drawn larger than its source resolution, point sampling (nearest-neighbour) gives blocky squares. This method instead takes the 2×2 block of texels around the sample point and interpolates linearly in both the horizontal and vertical directions — hence bi-linear. The result is smooth but slightly blurry, and it does nothing for minification, where distant textures still shimmer; that needs mipmaps and trilinear filtering. Standard on every GPU since the mid-1990s — the 3dfx Voodoo made it a selling point in 1996 — it is effectively free today and the default sampler state almost everywhere.