Reshaping a sphere with a bump map
 

Hi, could someone please tell me how to make the vertexes of a sphere form mountains and valleys from a bump map in Maya? I know how to make a sphere and texture it, but I don't know how to do the other part. Here's the bump map I want to use.

http://read.pudn.com/downloads83/sou.../earthbump.png

Bump mapping doesn't have the ability to actually change the geometry in anyway, just the shading, so they won't do well for mountains but displacement mapping will.

Here is how to apply it as a bump map. This does not actually displace the surface it only gives the illusion of depth. The default values were used.

To actually display the surface select displacement from the bump map drop down menu. I have not played with displacement much. I am not sure but you make have to increase the mesh density of the initial sphere. Experiment and see what you get. Report back.

Remember to apply the lambert shader to the sphere. I left that step out. I saved the wrong image for step 4b and I am to lazy to reload. All it has is a line pointing to the bump map folder row and says enter the path to the bump map image.

Good luck. I tossed this together very quickly I hope it is useful.

Here is what is produced:

http://i181.photobucket.com/albums/x.../th_step06.jpg

Here are the steps:

http://i181.photobucket.com/albums/x.../th_step01.jpg http://i181.photobucket.com/albums/x.../th_step02.jpg http://i181.photobucket.com/albums/x...th_step03a.jpg

http://i181.photobucket.com/albums/x...th_step03b.jpg http://i181.photobucket.com/albums/x...th_step04a.jpg http://i181.photobucket.com/albums/x...th_step04b.jpg

http://i181.photobucket.com/albums/x.../th_step05.jpg

Thank you for putting all that together for me, but unfortunately I had the wrong name. I need to make it from a height map, not a bump map. Should I use displacement? I don't want to create the illusion of depth, I want the mesh to actually change. Here's a height map I found, though I need one that has the ocean floor too.

http://earthobservatory.nasa.gov/Fea....5400x2700.jpg

Same process.

The bump map channel has three modes bump (give illusion of depth), displacement (actually displaced the geometry), and normal (once again just give illusion of depth but is based on actual geometry instead of a grey scale image).

From the height map it appears to have far less data then the other map. But the process is exactly the same. Just chose the displacement option from the bump drop down menu.

As I said I don't have any experience with displacement so I don't know if you have to already have the necessary mesh density or not. You will have to experiment with it. All the stuff I did is exactly what you have to do except select displacement instead of bump.

For the displacement map the poly count has to be high (say 250 x 250 or may be more) . I feel the file has very less data for the kind of results you have in mind.

One option of displacement is in sculpt geometry tool under Polygon menu set.

Under attribute maps import the file name. Keep Import value as luminance. You need to play with the max displacement value. start with 200. Operation will be pull.

Mahesh

Thank you, I'll try to figure it out today. The height map I got could be better, but I have to rewire a USB cable today, directly to the plug, not by wire splicing, so I probably won't have much time left over to find a better one that includes the ocean floor and has better overall definition, if that's the right word. If anyone's bored and wants to find me one like that I'd really appreciate it. It's for a gift for my father's birthday. He often says he's been around the world, because in the late 60's he went overseas for the military, so I'm making him a minigame with Blitz 3d called, second time around the world. It's like the Final fantasy 7 worldmap, exaggerated topography and all, but of our Earth.

http://www.youtube.com/watch?v=cberdd5Qses

I figured out how to do it with the YouTube video above, but I used an image file instead of the crater method he used. I still need to know how to set what the lowest and highest points will be though. In the one I made, the effect was too slight. I also ended up with a mesh that was too dense, and when I tried to reduce it, it ended up looking like a morningstar. Please help if you can.