Makie v0.23.0

Makie 0.23.0 is a relatively small breaking release before the big 0.24.0 ComputePipeline refactor. Its only breaking change is the arrows() refactor.

Arrows

Arrows have been refactored to address a number of issues, most importantly issues with scaling and alignment. Before 0.23, arrows did not consider the arrow tip as part of the length, which meant that arrows were always longer than they should be. This also applies to alignment, where align = :tip would align arrows to the endpoint of the shaft (called tail pre-0.23) instead of the end of the tip.

The new arrows2d and arrows3d now strictly follow the rule that the drawn arrow length must match the length derived from directions, normalize and lengthscale. To achieve this, the arrow shaft may elongate or the whole arrow may scale.

As you can see, short arrows shrink while long arrows get a longer shaft. This is controlled by minshaftlength and maxshaftlength. If the calculated shaft length falls in this range, the shaft is scaled to that length. If it does not, the length is clamped to that range and the full arrow is scaled instead. If you want just shaft length scaling, you can set minshaftlength = 0. (Scaling will still happen if the shaft length drops to/below 0.) If you want just scaling, you can set shaftlength to a fixed value.

The styling attributes arrowsize, linewidth, arrowtail, and arrowhead have been broken up and renamed. There are now three components to an arrow: the (usually 0-length) tail, shaft, and tip. Each has a length and width (2D) or radius (3D). In 2D they are given in markerspace, i.e., pixel space by default. Unlike before, they are not necessarily the true size of the final arrow, as scaling can still apply. In 3D they are given in a bounding box relative space if markerscale = automatic (default), or in data units scaled by markerscale if it is set to a number. The tail, shaft, and tip can each be set to a vector of points (2D) or mesh to change the look of the arrows.

The total arrow length follows from the direction argument, lengthscale, and normalize. If normalize = true, directions are normalized first. Then they are multiplied by lengthscale. The result is the target length of the arrow, which the drawn arrow marker must be equal to.

The align attribute has been reduced to only accepting :tail, :center, :tip, or a number. :tail (0) and :tip (1) are the two endpoints of the arrow, and :center (0.5) is the center of the full arrow. Note that you can also create a gap by setting align to a value outside the 0..1 range.

Another addition is argmode, which allows you to change the interpretation of the second argument. With argmode = :endpoint, the second argument is treated as the target position for the tip. The directions are then derived from that, with normalize and lengthscale applying afterwards. align works a bit differently in this mode. Instead of aligning a fraction of the final arrow with the origin (first argument), it aligns that fraction with the same fraction between the endpoints. So with align = :center, the center of the arrow aligns with the center of the two endpoints.

All of these concepts also apply to arrows3d:

Note that arrows2d and arrows3d can both be used in 2D and 3D space. They differ in how they represent arrows - as a 2D mesh or a 3D mesh, respectively. Note as well that we introduced Cone(origin, extremity, radius) as a GeometryPrimitive in GeometryBasics with this release.

#4925

Dendrogram

We have finally added the dendrogram recipe. Given a collection of leaf node positions and merge indices, a tree visualization is created.

#2755

Backlog

In the following sections, we want to highlight some changes that happened since the last blog post for Makie 0.22.2.

Makie 0.22.8

Annotation

There's a new annotation recipe which can be used to annotate data points with text labels and connecting arrows or other styles. If no specific label positions or offsets are given, the default behavior tries to move labels away from data points, other labels, and the figure boundary. This results in better readability for quick plots compared to a simple text annotation:

Annotation labels can be placed either in data space or relative to the target points in screen space, making it easy to achieve a consistent visual result regardless of axis scaling:

Annotations can come in a variety of styles, which will also be expanded in the future. Currently, lines and arrows of different shapes are supported:

#4891

Makie 0.22.5

Legend entries for mesh, meshscatter, image, heatmap and surface plots

Legend now has entry visualizations for mesh, meshscatter and surface in 3D and image and heatmap in 2D:

#4924

Hide/show interaction for Legend

You can now toggle the visibility of plots by left-clicking their respective Legend entries. Right-clicking will toggle all connected plots, and middle-clicking will synchronize and toggle them.

#2276

PolarAxis Ticks

PolarAxis now supports ticks (lines between tick labels and the axis frame). The related attributes are r-, rminor-, theta-, and thetaminor-:

• -ticksvisible: Are ticks shown (default false)

• -ticksize: Controls the length of ticks

• -tickwidth: Controls the width of ticks

• -tickcolor: Controls the color of ticks

• -ticksmirrored: Swaps the tick location to the opposite end of the PolarAxis if the PolarAxis doesn't span a full circle ( rmin > 0 or thetamax - thetamin < 2pi)

• -tickalign: Controls the alignment of ticks relative to the frame (default 0, point outwards)

#4902

Anisotropic marker rendering in GLMakie & WGLMakie

Rendering scatter markers (or text) with anisotropic markersize (or fontsize), e.g., markersize = Vec2f(10, 50), used to result in blurred or pixelated edges in WGLMakie and GLMakie. The reason for this is that the signed distance fields representing markers (characters) are generated at a different aspect ratio. We have now added a correction for this in shaders, which greatly reduces the blurring/pixelation:

                
using GLMakie
scene = Scene(size = (250, 250))
ms = [Vec2f(60, 10), Vec2f(60), Vec2f(10, 60)]
scatter!(scene, fill(-0.75, 3), [-0.75, 0.0, 0.75], marker = :rect, markersize = ms)
scatter!(scene, fill(0, 3), [-0.75, 0.0, 0.75], marker = :circle, markersize = ms)
scatter!(scene, fill(0.75, 3), [-0.75, 0.0, 0.75], marker = 'L', rotation = pi/3, markersize = ms)
scene
              

Before	After

#4918

Makie 0.22.3

Textlabel

We added a new textlabel recipe which plots text with a background.

#4879

space and transformation changes

space and plot transformations used to be intertwined. For example, transform functions used to consider space, essentially running:

                
function apply_transform_func(func, data, space)
    if is_data_space(space)
        apply_transform_func(func, data)
    else
        return data
    end
end
              

This meant you could never have a transform_func apply to a plot that is not in data space. It also suggested that space should control which transformations get applied, which would mean that each of the current space options should be split into four (with and without model and transform_func).

On the other hand, we were also checking space compatibility between plots and their parents during construction, only inheriting transformations if they were compatible. So a plot with space = :pixel (and a parent that isn't in pixel space) would have identity transformations unless they were explicitly passed, meaning that applying them wouldn't actually change anything. We decided to rely on this as the source of truth. As such:

• plots now always apply their transform_func

• transformations can be explicitly (not) inherited by setting plot(..., transformation = :inherit/:inherit_model/:inherit_transform_func/:nothing)

#4792

Scatter font

You can now set the font used for rendering Char markers in scatter plots.

#4832