Color a sphere surface/polar plot axis-wise

Hi there,

I would like to produce both a sphere and a polar plot whose surface color is defined at each XYZ axis as follows:

Top-bottom (Z) = blue

Left-right (Y) = red

Anterior-posterior (X) = green

The color in the boundaries/interfaces should be an interpolation of them.

Such as here:

http://bit.ly/1WrpG8d

and here (for the polar plot):

http://bit.ly/1WrpzcP

I have been googling for a while but did not find much help to do it.

Thanks,

Jon

PS: Similar questions seem to have been asked previously with a few variants, but the answers given seem not reproduce the figures pointed above.

Answer 1

[Mike Garrity]

Something like this, perhaps?

[x,y,z] = sphere(40);
col(:,:,1) = abs(y);
col(:,:,2) = abs(x);
col(:,:,3) = abs(z);
surf(x,y,z,col,'FaceColor','interp','EdgeColor','none')
axis equal
camlight

Here's a start on the "polar" one, but I'll let you add the grid & text.

view(2)
axis off
set(gca,'CameraUpVector',[1 0 0])
delete(findobj(gca,'Type','light'))

[Jon Legarreta]

Hi Mike,

thanks for your answer. Helps a lot !

I successfully added the sticks and the text to the sphere using

[X,Y,Z] = cylinder(cylinderRadius, cylinderResolution);
Z(2,:) = -(Z(1,:) + cylinderLength/2);
Z(1,:) = Z(1,:) + cylinderLength/2;
siStick = mesh(X,Y,Z,'FaceColor','b','EdgeColor','none');

yRotAx = [0 1 0]; % rotation around y-axis
rotate(lrStick, xRotAx, angle);

text(siStick.XData(1,1),siStick.YData(1,1),siStick.ZData(1,1) + offset,'S',...
  'HorizontalAlignment','left','Color','b','FontSize',textSize);

Although it does not seem the easiest way, I did not find the way to do it thorough simpler transformations/functions.

As for the disc, I am having a hard time trying to mimic the way I set the text for the sphere case, and I am not succeeding.

Did not attempt the grid.

Any hints?

Thanks