3D terrain graph with colour (as 4th dimension of dataset)

Specific Domains Geo
,
1

Hello,

Relatively new to Julia and enjoying it a lot! However, I would like to display data that has 4 dimensions, x, y, z (terrain) with a color that is independent of z. For context I’m trying to display geophysics on top of a terrain map. I’ve gone through Makie.jl, PlotlyJS.jl and Plots.jl and can’t quite find anything that suitable.

Do I need to transform my terrain data into an stl file and than overlay it with color using Makie.jl perhaps?

Any ideas to modules to consider would be great!
Thanks

2

See the GMT.jl module grdview. You want specifically the option drape.

3

Do you mean something like this?

using GLMakie
using DelimitedFiles


volcano = readdlm(Makie.assetpath("volcano.csv"), ',', Float64)
color = rand(size(volcano)...)

surface(volcano;
    color,
    axis=(type=Axis3, azimuth = pi/4))

image
image1424×1180 194 KB

1 Like
4

This is a PlotlyJS example. x,y are artificially added, because my data file contains only information on z.
Your color (the 4th dimension) should be assigned to surfacecolor. Here it is set surfacecolor= z.

using DelimitedFiles, PlotlyJS

z = readdlm("st-helens-before.txt", ' ')
r, c = size(z)
x = 1:c
y = 1:r

fig=Plot([surface(x=x, y=y, z=z, surfacecolor=z, 
        colorscale=colors.gist_earth, colorbar_thickness=25, colorbar_len=0.75
        ), surface(x=x, y=y, z=-1000*ones(size(z)), surfacecolor=z,
                        colorscale=colors.gist_earth,
                        showscale=false)],
Layout(width=500, height=500, font_size=10, scene_camera_eye=attr(x=1.6, y=1.6, z=1)))

St-Helens-before

1 Like
5

I’ll add this as an example of grdview plus draping an external image.

using GMT

# Get the Gulf of Guinea grid
G = grdcut("@earth_relief_01m", region=(0,10,0,10));

# Drape a photo of a cork tree trunk over it
grdview(G, shade="+nt0.5", proj=:merc, view=(145,35), drape="@wood_texture.jpg",
             zsize=5, surftype=:img, name="texture.jpg", show=true)

texture
texture1920×1262 174 KB