Hello Everyone,

In Paul Auster's the Brooklyn Follies, there is one part I can't fully understand.

...Smith's work had everything. Boldness, color, energy, and
light. Figures swirled through fierce, slashing strokes of paint,
vibrating with an incandescent roar of emotion, a human cry
so deep, so true, so passionate, that it seemed to express both
joy and despair at the same time...

What does the two underlined mean here? Can you give the equivalence to me?

Thanks and Regards