  By integrating across the light-cone energy, totally unintegrated,
off-diagonal quark-quark generalized parton correlation functions (GPCFs) can
yield generalized transverse-momentum dependent parton distributions (GTMDs).
We have obtained the twist-4 GTMDs for the case of proton in the light-front
quark-diquark model (LFQDM). We have decoded the quark-quark GTMD correlator
for proton and solved the parametrization equations for Dirac matrix structure
at twist-4. We have derived the explicit equations of GTMDs for the diquark
being scalar or vector leading to the results for the struck quark being a $u$
or $d$ quark. Being a multidimensional function, the dependence is studied with
two variables at a time, keeping the others fixed. Transverse-momentum
dependent form factors (TMFFs) have been obtained from GTMDs via integration
over the longitudinal momentum fraction $x$ of the quark. We have debated over
the possibility to specify the initial and final state polarizations of the
smacked quark and the nucleon in twist-4 GTMDs as well as the Wigner
distributions. Additionally, from twist-4 GTMDs, we have deduced the twist-4
T-even TMDs and found its synchronization with the already published results.
