7
$\begingroup$

I am trying to texture a sphere with a picture of myself. I don't want it to be stretched across the whole sphere but only to appear on the front. I used

SphericalPlot3D[1, {Theta, 0, Pi}, {Phi, 0, 2 Pi},
  PlotStylye -> Texture[image],
  TextureCoordinateFunction -> ({#5, 1 - #4} &)]

While this fixed the direction of the picture I cannot figure out how to shorten it so it's not stretched across the whole sphere. When I type in ImageDimensions[image,] it gives the image dimensions as {1440, 2560} if that helps at all.

$\endgroup$
7
$\begingroup$

A quick and dirty way to do this is to pad the image with pixels of some inoffensive color, so that the actual meaningful part of the image gets mapped to a smaller portion of the sphere:

image = Import["ExampleData/ocelot.jpg"];
{width, height} = ImageMeasurements[image, "Dimensions"];
image = ImagePad[image, {{2 width, 2 width}, {height, height}}, White];
SphericalPlot3D[1, {Theta, 0, Pi}, {Phi, 0, 2 Pi}, PlotStyle -> Texture[image], 
  TextureCoordinateFunction -> ({#5, 1 - #4} &), ViewPoint -> Left]

The first three lines create a new version of your image that's padded with white pixels on all sides; you'll need to play around with your values to get the aspect ratio right. Projecting this image onto the sphere then yields the following:

enter image description here

Note that I changed the ViewPoint in order to get the image on the "front" of the sphere. With the default viewpoint, you end up with the image about 3/4 of the way to the other side of the sphere.

The other way to do this would be to set TextureCoordinateScaling -> False and then rescale your TextureCoordinateFunction (put numbers in front of #5 and #4 and see what happens.) But I'm not sure if there's a way to do this without having the image repeat itself ad infinitum.

$\endgroup$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.