Compose multiple images into a single figure — compose

Arranges rendered images (from render_mesh() or render_scene()) into a grid layout and optionally appends a colorbar. All composition is done with pure R array operations.

Usage

compose_layout(
  images,
  nrow = NULL,
  ncol = NULL,
  colorbar = NULL,
  colorbar_height = 80L,
  colorbar_width = 80L,
  background = c(0, 0, 0, 0),
  colorbar_side = c("right", "left"),
  crop = FALSE
)

Arguments

images: A list of images, each a list with width, height, pixels as returned by render_mesh().
nrow: Number of rows in the grid layout.
ncol: Number of columns in the grid layout. If both nrow and ncol are NULL, a square-ish layout is chosen automatically.
colorbar: Optional colorbar array (from colorbar_horizontal() or colorbar_vertical()). Placed below if horizontal, to the right if vertical.
colorbar_height: Height of the colorbar row in pixels. Only used when appending a horizontal colorbar.
colorbar_width: Width of the colorbar column in pixels. Only used when appending a vertical colorbar.
background: Background RGBA color for padding (0-1 scale).
colorbar_side: For vertical colorbars, whether to place the bar on the "right" (default) or "left" of the brain images. Ignored for horizontal colorbars.
crop: Logical. If TRUE, transparent borders are cropped individually and images are padded to per-row height and per-column width for a tight layout with minimal white space. Default is FALSE (images must be same size).

Value

A list with width, height, pixels suitable for write_png() or image_to_array().

Examples

mesh1 <- generate_cuboid(c(-1.5, 0, 0), c(0.5, 0.5, 0.5), c(1, 0, 0, 1))
mesh2 <- generate_cuboid(c( 1.5, 0, 0), c(0.5, 0.5, 0.5), c(0, 0, 1, 1))
img1 <- render_mesh(mesh1$vertices, mesh1$triangles)
img2 <- render_mesh(mesh2$vertices, mesh2$triangles)
result <- compose_layout(list(img1, img2), nrow = 1L)
tmp_file <- tempfile(fileext = ".png")
write_png(result, tmp_file)