Bound surface limits to a function
ConditionalExpression
Plot3D[ConditionalExpression[Sin[x y], Sin[x y] > x^3 + y],
{x, -1, 1}, {y, -1, 1}, PlotRange -> {{-1, 1}, {-1, 1}, {-1, 1}}, Mesh -> None]
To show both functions
Plot3D[{ConditionalExpression[Sin[x y], Sin[x y] > x^3 + y], x^3 + y },
{x, -1, 1}, {y, -1, 1}, PlotRange -> {{-1, 1}, {-1, 1}, {-1, 1}},
Mesh -> None, BaseStyle -> Opacity[.7]]
MeshFunctions, MeshShading
Plot3D[Sin[x y], {x, -1, 1}, {y, -1, 1},
PlotRange -> {{-1, 1}, {-1, 1}, {-1, 1}},
MeshFunctions -> {Sin[# #2] - #^3 - #2 &}, Mesh -> {{0}},
MeshShading -> {None, Automatic}, BoundaryStyle -> None]
ImplicitRegion
ir = DiscretizeRegion @ ImplicitRegion[Sin[x y] > x^3 + y, {{x, -1, 1}, {y, -1, 1}}];
Plot3D[Sin[x y], {x, y} ∈ ir, PlotRange -> {{-1, 1}, {-1, 1}, {-1, 1}}, Mesh -> None]
You can utilize the option RegionFunction
for that:
Plot3D[{Sin[x y], x^3 + y}, {x, -1, 1}, {y, -1, 1},
Mesh -> None,
RegionFunction -> ({x, y, z} \[Function] Sin[x y] > (x^3 + y))
]