Simple patch drawing

[StreetLevel]

Hi,
sometimes it would be useful if one could draw 2D and 3D Matlab-like patch objects via Plots.jl:

For me it would be useful for visualizing small finite element models in Julia without using a post processing tool but I think it's useful in many other cases too.
I think it's a basic feature for a plotting library and should be implemented in Plots.jl

Best, Max

[tbreloff]

seriestype = :shape

…

On Thu, Dec 8, 2016 at 2:26 PM StreetLevel ***@***.***> wrote: Hi, sometimes it would be useful if one could draw 2D and 3D Matlab-like patch objects via Plots.jl: [image: patch] <https://cloud.githubusercontent.com/assets/12096700/21011334/12302100-bd51-11e6-9079-7864bb60c188.png> For me it would be useful for visualizing small finite element models in Julia without using a post processing tool but I think it's useful in many other cases too. I think it's a basic feature for a plotting library and should be implemented in Plots.jl Best, Max — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub <#605>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AA492jH5ETAnbJKQQoe5B3EZNMHjO_Ccks5rGAV_gaJpZM4LH0MA> .

[StreetLevel]

Ok thank you, I have to look into that.

Is it possible to interpolate nodal color data like this?

[tbreloff]

There's nothing like this built into Plots. I'm curious how you'd use this in practice (i.e. why is it useful?)

[RaulDurand]

I would find this useful in some numerical methods as for example in the Finite Element method where nodal interpolation is usually done to better visualize fields (as displacement, temperature, etc.)

[zaz1588]

I am migrating from MATLAB as well and visualizing data over an triangular mesh is paramount to my work. I made a small example that could showcase the usefulness of this. Using delaunay to create a triangular mesh over random points and and coloring each triangle with the Y position. I still did not manage to get a colorbar to show up. Any ideas? I tried to figure out how to use the seriestype = :shape tip but could not figure out how to use @recipes. To the best of my knowledge, there is no way to plot a triangular mesh in 3D. Doing that is quite straightforward with PyPlot or plotly and that is how I am doing those plots now but I would rather use Plots.

using VoronoiDelaunay
using Plots
##
N = 100
x = 1.0 + rand(N)
y = 1.0 + rand(N)
tess1 = DelaunayTessellation()
pts1 = [Point(x[n], y[n]) for n=1:N]
push!(tess1, pts1)
##
scatter(x, y,leg=false,palette=:heat)
for i in tess1
  t=Shape([geta(i)._x,getb(i)._x,getc(i)._x],[geta(i)._y,getb(i)._y,getc(i)._y])
  plot!(t,fill = (0, 0.5, RGB(geta(i)._y-1, geta(i)._y-1, geta(i)._y-1)))
end
gui()

[mkborregaard]

see also the discussion here #392

[mkborregaard]

Can't you do this with surface (or heatmap in @StreetLevel 's case above) while passing the area as a matrix, see e.g. #479 ?

[zaz1588]

#479 deals with regular grids. doesn't work with triangles.
#392 is basically the same as this.
Heatmap only works for regulars grids. doing it for unstructured triangulargrids is the issue here. as I tried to show in my example.