The old linear profilers were a pretty crude concept, but so darn solidly built that they worked quite well and fast for heavy cuts in furniture rails and such, so would seem to be adaptable to light cuts on cues for any taper desired.
"profile shaper" seems to be the preferred description, I learned the other term long ago from an old machinery dealer
Basically a carriage that traveled lengthwise past a shaper spindle, with a top platform pivoted at one end, and either spring/air/hydraulic loaded against a collar at the shaper spindle. The top platform had provision for a pattern ("taper bar) to ride the collar. So as the carriage was automatically cycled past the shaper cutter, the blank moved in and out against the collar to according to the installed pattern (or taper bar). Feed is variable, a saw blade could be mounted on the spindle, or for furniture, shaper cutters.
Alternately, the T-slot table travels in a straight line with a pattern on one edge, and the spindle assembly pivots & is spring loaded to maintain contact with the pattern, and cuts to mirror the pattern as it goes, this seems to be more common for modern and for 2 sided machines.
http://www.irsauctions.com/popups/hirespics/?pict=389295A&lot=389295&letter=A&auc=
http://www.vintagemachinery.org/pubs/610/5100.pdf
When i started to make cues as a hobby again I set my planer up on the same principle as a profile shaper & contrived a router head in the tool slide. The platform under the powered center-set swivels on a stripper bolt at the far end, and is spring loaded to bear against a large radius (for low wear) follower bolted to the left planer column. As the table traverses, the waxed microlam plywood pattern on the edge controls the cut on the shaft.
Of course the pattern can be modified by the height of the cutter, and whether the centers are parallel in height, or shimmed to be different. As an extreme example, a hyperbolic curve can be generated on the shaft by raising the tip end, and skewing the centers to the line of travel, while just running the table in a straight line with no pattern or induced swivel motion.