Fog along Y axis?

is there a way to apply fog along y or x axis not only z axis?

GL_EXT_fog_coord can do it. With this, you can specify fog ‘depth’ values per vertex, these are still transformed through the fog equation to produce fog blending weights. Fairly flexible stuff and supported by a wide range of hardware.

thank you i’ll try it. i thought so that it would be natural that depth coordinate would be suitable for fog naturally
much thanks

To apply “fog” based on window space x/y, try blending with an alpha textured quad.