### Convex $\mathbb{R}\mathsf{P}^2$ Structures

Hyperbolic triangle groups are * rigid*, a fact easily believed once one remembers that a hyperbolic triangle is completely determined by its angles.
However, these groups admit nontrivial deformations into $\mathsf{SL}(3;\mathbb{R})$, geometrically describing *convex real projective structures*.