The −C≡C− is normally drawn as linear about each C atom as that is what is found in nature for most alkyne x-ray crystal structures. We can use hybridization theory to explain this as the C atoms would be expected to adopt an sp hybridization, which gives two hybrid orbitals along the axis of the p orbital hybridized with the s to make the sp hybrids:
These orbitals will then overlap with orbitals on adjacent atoms to make two sigma bonds in a linear arrangement about each C atom, giving alkynes their overall linear shape:
Cycloalkynes tend to be strained molecules as the ideal bond angles of $180^o$ about the alkyne C atoms are not consistent with a small cyclic molecule. This causes cycloalkynes with less than 10 C atoms to have measurable strain and the strain increases as the ring gets smaller:
Chemical drawing programs will tend to keep the general shape of a cyclic structure (a heptagon in the case of molecule f) and just add the triple bond, but it does do a good job of indicating to us that the molecule will suffer from this strain as it naturally tends to deviate the angles away from $180^o$!