This function is very similar to the
`image`

function. It works with every loon plot which
is based on the cartesian coordinate system.

l_layer_heatImage(widget, x = seq(0, 1, length.out = nrow(z)),
y = seq(0, 1, length.out = ncol(z)), z,
zlim = range(z[is.finite(z)]), xlim = range(x), ylim = range(y),
col = grDevices::heat.colors(12), breaks, oldstyle = FALSE,
useRaster, index = "end", parent = "root", ...)

## Arguments

widget |
widget path as a string or as an object handle |

x |
locations of grid lines at which the values in z are measured. These
must be finite, non-missing and in (strictly) ascending order. By default,
equally spaced values from 0 to 1 are used. If x is a list, its components
x$x and x$y are used for x and y, respectively. If the list has component z
this is used for z. |

y |
see description for the `x` argument above |

z |
a numeric or logical matrix containing the values to be plotted
(`NA` s are allowed). Note that `x` can be used instead
of `z` for convenience. |

zlim |
the minimum and maximum `z` values for which colors
should be plotted, defaulting to the range of the finite values of
`z` . Each of the given colors will be used to color an
equispaced interval of this range. The *midpoints* of the
intervals cover the range, so that values just outside the range
will be plotted. |

xlim |
range for the plotted x values, defaulting to the range of x |

ylim |
range for the plotted y values, defaulting to the range of y |

col |
a list of colors such as that generated by
`rainbow` , `heat.colors` ,
`topo.colors` , `terrain.colors` or similar
functions. |

breaks |
a set of finite numeric breakpoints for the colours:
must have one more breakpoint than colour and be in increasing
order. Unsorted vectors will be sorted, with a warning. |

oldstyle |
logical. If true the midpoints of the colour intervals
are equally spaced, and `zlim[1]` and `zlim[2]` were taken
to be midpoints. The default is to have colour intervals of equal
lengths between the limits. |

useRaster |
logical; if `TRUE` a bitmap raster is used to
plot the image instead of polygons. The grid must be regular in that
case, otherwise an error is raised. For the behaviour when this is
not specified, see ‘Details’. |

index |
position among its siblings. valid values are 0, 1, 2, ...,
'end' |

parent |
parent widget path |

... |
argumnets forwarded to `l_layer_line` |

## Value

layer id of group or rectangles layer

## Details

For more information run: `l_help("learn_R_layer.html#countourlines-heatimage-rasterimage")`

## Examples

#> loon layer "rectangles" of type rectangles of plot .l63.plot
#> [1] "layer0"