Vasari’s classic opposition of line and color (disegno e colorito) melts on the canvases of Robert de Niro Sr. like gelato in a hot, hungry mouth. He drew not merely in, but with, color: Nudes and still-life motifs alike seem at once caressed and assaulted by his brush – at times pigment-loaded, at others breathily running out of juice. Even when he does seem unhealthily addicted to outline – thick black serpentine borders penning-in pulsating pockets of autonomous color – there is such painterly bravura to his line and structure to his color that the competing properties bounce back and forth.

He is the subject of a long-overdue monograph ($125) by L.A.-based former Village Voice critic Peter Frank published by Salander-O’Reilly Galleries, which represents the artist’s estate. The handsomely designed tome atones for the pompously framed and oppressively overhung (but finely chosen) selection of work at the gallery that accompanies their publication.

De Niro was a star pupil of Hans Hofmann’s legendary schools (he studied with the German expatriate both in Provincetown and New York), which produced a whole firmament of alumni: Stella, Frankenthaler, Kahn, Krasner, Matter, and Grooms, amongst others. Two others, indeed, are also shown at Salander: Paul Resika and the late Louisa Matthiasdottir. De Niro shares traits with both – chromatic hedonism with the former, intense shape consciousness with the latter – without anyone seeming less original for the commonalities.

What De Niro has that’s uniquely his own is a manic yet angst-free expressivity: At times this can be a mannerism, the compulsive need for dashed-off, late-for-the-train brushmarks. But it is remarkable how often such marks actually make perfect emotional and compositional sense. The real payoff of his bravura is the high incidence of resonant ambiguity it engenders.

Take, for instance, “Nudes on a Yellow Background” (1975), a gem from his maturity. Two nudes disport themselves in an interior. One sits legs akimbo: She is a miracle of muscle. With compelling painterly economy (or, equally, you could argue, extravagance) she is built out of a few thick, streaked strokes; one glides its way from head to shin with anatomically convincing yet pictorially gracious ease. The second nude, behind her, attends to the red vase of flowers on the deftly perfunctory occasional table that commands the right-hand side of the composition.

But if you linger as the gorgeous, breezy paintwork invites, you begin to wonder: Are there really just two of them? What passes at first as gratuitous filler, a splash of Prussian blue between the protagonists or a scumble of burnt umber in the left corner of the picture – making autonomous, compositional (abstract) sense but not demanding to be read with any precision – can actually take on tantalizingly figural possibilities.

The first loop of the Prussian blue flourish looks like arms held in supplication, after which the return drop becomes a dainty back. The umber shape then starts to frolic on the woman’s knee. Are these children, perhaps, or putti even? Better things still begin to happen with what really should just be neutral ground, the yellow of the title: Underneath the crisply painted, faintly phallic table, a prong like negative shape emerges that almost seems to pinch an area of strawberry pink behind it into significant form. There’s almost as much fleshly umph in this yellow as in the ample flesh of the nudes.

Streaks of white light give suggestive volume to what can, in fact, read like fingers, and the shape takes on psychological value: It doesn’t seem like over-reading to think of this as the presence of the artist (the scale would make optical sense), teasing out formal values from what is framed by his gaze, manipulating shape into meaning.

He may have avoided the angst that defined his existentialist generation, but De Niro was capable of pathos. It is clear from the 1954 self-portrait, and even from his 1963 transcription of “Delacroix’s Women of Algiers,” that he was in awe of Rouault, the most somber of the French expressionists. Among his later writings, reproduced in the present volume, are telling appraisals of Soutine and Munch. But in his own work, even the glorious, ambitious crucifixions sing with sensuality: Light-filled feasts of color, they are icons of redemption rather than narratives of suffering.

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If De Niro is an example of a marginal painter who gives singular pleasure, his teacher is the opposite: Hofmann is a seminal figure but there is invariably something problematic, disappointing, confusing, even aesthetically offensive about his work. This is not to deny his historic importance, but sometimes he seems major despite his painting.

Ameringer & Yohe have a selection of breakthrough Abstract Expressionist works by Hofmann from the 1940s, a few years after De Niro left his charge. The catalog publishes an unusual document: an encomium by hot-property, anime-influenced “bad girl” painter Inka Essenhigh. “I don’t know if he looked at cartoons,” she wonders, “but he might as well have.” His playful speed, she reckons, has “Warner Bros. zippiness.”

Making Hofmann a link to her own idea of Surrealist automatism is doubly curious, as unconscious doodling seems contrived and incidental to both of them. Hofmann couldn’t be more different from the squeaky, clean-machine finesse of both Warner Bros. and Ms. Essenhigh: His color is at once turgid and abrasive, and his painterly hand, even at its most expressively awkward,falls short of any convincing sense of unconscious release.

Ms. Essenhigh plays games in her work with contrasts in attention span, with pockets of fuss and fiddle isolated on deep, saturated fields of (oxymoronically) pure synthetic color. In Hofmann such games have an entirely different meaning: They contrive to dislocate a sense of scale and thus achieve the kind of push pull between two- and three-dimensionality (the actual and the optical) that he so valued. But they also conspire to deprive his compositions of both the central, organizing unity and the unconstrained expressiveness of, say, de Kooning or Pollock.

It is ironic, when you consider the quality and conservatism of Hofmann’s best pupils, that Ms. Essenhigh now has us thinking of him as a progenitor of de rigeur “Bad” painting.

Robert De Niro Sr. until February 5 (20 E. 79th Street, between Fifth and Madison Avenues, 212-879-6606). Prices: $75,000-$500,000.

Hans Hoffman until February 5 (20 W. 57th Street, between Fifth and Sixth Avenues, 212-445-0051). Prices: $2,800-$650,000.