tricontour

Makie.tricontour Function

tricontour(triangulation, zs; kwargs...)
tricontour(xs, ys, zs; kwargs...)

Plots isolines of the scalar field zs at the horizontal positions xs and vertical positions ys on an unstructured triangular grid. A Triangulation from DelaunayTriangulation.jl can also be provided instead of xs and ys, otherwise an unconstrained Delaunay triangulation of xs and ys is computed.

Plot type

The plot type alias for the tricontour function is Tricontour.

source

Examples

using CairoMakie
using Random
Random.seed!(1234)

x = randn(200)
y = randn(200)
z = sin.(2π .* x) .* cos.(2π .* y)

f, ax, tr = tricontour(x, y, z; levels = 10)
Colorbar(f[1, 2], tr)
f

Setting color to a fixed value draws all isolines in that color instead of sampling from the colormap.

using CairoMakie
using Random
Random.seed!(1234)

x = randn(200)
y = randn(200)
z = sin.(2π .* x) .* cos.(2π .* y)

f, ax, tr = tricontour(x, y, z; levels = 10, color = :black, linewidth = 1.5)
f

Explicit isoline values can be passed as a vector.

using CairoMakie
using Random
Random.seed!(1234)

x = randn(200)
y = randn(200)
z = -sqrt.(x .^ 2 .+ y .^ 2) .+ 0.1 .* randn.()

f, ax, tr = tricontour(x, y, z; levels = -1.5:0.3:0.0, colormap = :plasma)
Colorbar(f[1, 2], tr)
f

Triangulation modes

A pre-built Triangulation from DelaunayTriangulation.jl can be passed as the first argument instead of xs and ys. Manual triangulations can also be passed as a 3×N integer matrix where each column specifies the vertex indices of one triangle.

using CairoMakie
using DelaunayTriangulation
using Random
Random.seed!(123)

n = 20
angles = range(0, 2pi, length = n+1)[1:end-1]
x = [cos.(angles); 2 .* cos.(angles .+ pi/n)]
y = [sin.(angles); 2 .* sin.(angles .+ pi/n)]
z = (x .- 0.5).^2 + (y .- 0.5).^2 .+ 0.5.*randn.()

inner = [n:-1:1; n]
outer = [(n+1):(2n); n+1]
boundary_nodes = [[outer], [inner]]
points = [x'; y']
tri = triangulate(points; boundary_nodes = boundary_nodes)

f, ax, tr = tricontour(tri, z; levels = 8, axis = (; aspect = 1))
Colorbar(f[1, 2], tr)
f

Attributes

alpha

Defaults to 1.0

The alpha value of the colormap or color attribute. Multiple alphas like in plot(alpha=0.2, color=(:red, 0.5)), will get multiplied.

clip_planes

Defaults to @inherit clip_planes automatic

Clip planes offer a way to do clipping in 3D space. You can set a Vector of up to 8 Plane3f planes here, behind which plots will be clipped (i.e. become invisible). By default clip planes are inherited from the parent plot or scene. You can remove parent clip_planes by passing Plane3f[].

color

Defaults to nothing

The color of the contour lines. If nothing, colors are sampled from colormap according to each isoline's level value. Otherwise all lines use this single color.

colormap

Defaults to @inherit colormap

Sets the colormap from which isoline colors are sampled when color is nothing.

colorrange

Defaults to automatic

The values representing the start and end points of colormap.

colorscale

Defaults to identity

The color transform function. Can be any function, but only works well together with Colorbar for identity, log, log2, log10, sqrt, logit, Makie.pseudolog10, Makie.Symlog10, Makie.AsinhScale, Makie.SinhScale, Makie.LogScale, Makie.LuptonAsinhScale, and Makie.PowerScale.

depth_shift

Defaults to 0.0

Adjusts the depth value of a plot after all other transformations, i.e. in clip space, where -1 <= depth <= 1. This only applies to GLMakie and WGLMakie and can be used to adjust render order (like a tunable overdraw).

fxaa

Defaults to false

Adjusts whether the plot is rendered with fxaa (fast approximate anti-aliasing, GLMakie only). Note that some plots implement a better native anti-aliasing solution (scatter, text, lines). For them fxaa = true generally lowers quality. Plots that show smoothly interpolated data (e.g. image, surface) may also degrade in quality as fxaa = true can cause blurring.

highclip

Defaults to automatic

The color for any value above the colorrange.

inspectable

Defaults to @inherit inspectable

Sets whether this plot should be seen by DataInspector. The default depends on the theme of the parent scene.

inspector_clear

Defaults to automatic

Sets a callback function (inspector, plot) -> ... for cleaning up custom indicators in DataInspector.

inspector_hover

Defaults to automatic

Sets a callback function (inspector, plot, index) -> ... which replaces the default show_data methods.

inspector_label

Defaults to automatic

Sets a callback function (plot, index, position) -> string which replaces the default label generated by DataInspector.

joinstyle

Defaults to @inherit joinstyle

Controls the rendering at corners. Options are :miter for sharp corners, :bevel for "cut off" corners, and :round for rounded corners. If the corner angle is below miter_limit, :miter is equivalent to :bevel to avoid long spikes.

levels

Defaults to 10

Can be either an Int which results in n equally-spaced isolines between the minimum and maximum of zs, or an AbstractVector{<:Real} that lists explicit isoline values from low to high.

linestyle

Defaults to nothing

Sets the dash pattern of the line. Options are :solid (equivalent to nothing), :dot, :dash, :dashdot and :dashdotdot. These can also be given in a tuple with a gap style modifier, either :normal, :dense or :loose. For example, (:dot, :loose) or (:dashdot, :dense).

For custom patterns have a look at Makie.Linestyle.

linewidth

Defaults to @inherit linewidth

Sets the width of the line in screen units

lowclip

Defaults to automatic

The color for any value below the colorrange.

miter_limit

Defaults to @inherit miter_limit

Sets the minimum inner join angle below which miter joins truncate. See also Makie.miter_distance_to_angle.

model

Defaults to automatic

Sets a model matrix for the plot. This overrides adjustments made with translate!, rotate! and scale!.

nan_color

Defaults to :transparent

The color for NaN values.

overdraw

Defaults to false

Controls if the plot will draw over other plots. This specifically means ignoring depth checks in GL backends

space

Defaults to :data

Sets the transformation space for box encompassing the plot. See Makie.spaces() for possible inputs.

ssao

Defaults to false

Adjusts whether the plot is rendered with ssao (screen space ambient occlusion). Note that this only makes sense in 3D plots and is only applicable with fxaa = true.

transformation

Defaults to :automatic

Controls the inheritance or directly sets the transformations of a plot. Transformations include the transform function and model matrix as generated by translate!(...), scale!(...) and rotate!(...). They can be set directly by passing a Transformation() object or inherited from the parent plot or scene. Inheritance options include:

• :automatic: Inherit transformations if the parent and child space is compatible

• :inherit: Inherit transformations

• :inherit_model: Inherit only model transformations

• :inherit_transform_func: Inherit only the transform function

• :nothing: Inherit neither, fully disconnecting the child's transformations from the parent

Another option is to pass arguments to the transform!() function which then get applied to the plot. For example transformation = (:xz, 1.0) which rotates the xy plane to the xz plane and translates by 1.0. For this inheritance defaults to :automatic but can also be set through e.g. (:nothing, (:xz, 1.0)).

transparency

Defaults to false

Adjusts how the plot deals with transparency. In GLMakie transparency = true results in using Order Independent Transparency.

triangulation

Defaults to DelaunayTriangulation()

The mode with which the points in xs and ys are triangulated. Passing DelaunayTriangulation() performs a Delaunay triangulation. You can also pass a preexisting triangulation as an AbstractMatrix{<:Int} with size (3, n), where each column specifies the vertex indices of one triangle, or as a Triangulation from DelaunayTriangulation.jl.

visible

Defaults to true

Controls whether the plot gets rendered or not.