Using themes to style 3D panels and axis labels

In ggcube, standard ggplot2 themes generally influence 3D plots as expected, including adding complete themes like ggplot2::theme_dark() and modifying theme elements like theme(panel.background = element_rect(fill = "darkblue"). However, ggcube also provides additional theme elements that control 3D-specific styling of panels and labels.

Text elements

axis.text.z: Styling for z-axis tick labels (inherits from axis.text)
axis.title.z: Styling for z-axis title (inherits from axis.title)
axis.text, axis.title: Standard styling with element_text().

Use element_text(margin = margin(...)) to adjust text padding, with left/right margins affecting axis text and top/bottom margins affecting axis titles; since placement and justification of these elements varies dynamically, no distinction is made between left and right margins, or between top and bottom margins – you can set either, and the maximum of the two will be used.

Panel elements

panel.foreground: Styling for cube faces rendered in front of data (inherits from panel.background). Foreground panels default to 20% opacity to keep them from obscuring the data; this can be overridden by setting alpha on either panel.foreground or panel.background.
panel.border.foreground: Styling for cube faces rendered in front of data (inherits from panel.border)
panel.grid.foreground: Styling for grid lines on foreground faces (inherits from panel.grid)
panel.grid.major.foreground: Major grid lines on foreground faces (inherits from panel.grid.foreground)

Background panels use standard panel.background, panel.border, panel.grid, etc., while foreground panels use the *.foreground variants listed above. Since the foreground elements inherit from the standard background and grid elements, you can use panel.background, etc. to style both background and foreground faces simultaneously. This also extends to alpha set via the enhanced element_rect() below: setting alpha on panel.background will tint both background and foreground panels (overriding the foreground's 20% default), unless an explicit alpha is also set on panel.foreground.

Enhanced elements

element_rect() extends ggplot2::element_rect() by adding an alpha parameter for transparency effects on coord_3d()'s foreground and background panels.

Examples

# example code
p <- ggplot(sphere_points, aes(x, y, z)) +
  geom_hull_3d() +
  coord_3d(panels = "all") +
  theme(panel.background = element_rect(color = "black"),
          panel.border = element_rect(color = "black"),
          panel.foreground = element_rect(alpha = .3),
          panel.grid.foreground = element_line(color = "gray", linewidth = .25),
          axis.text = element_text(color = "darkblue"),
          axis.text.z = element_text(color = "darkred"),
          axis.title = element_text(margin = margin(t = 30)), # add padding
          axis.title.x = element_text(color = "magenta"))