Blender - Displacement Maps

[ODdOnLifeItself]

Normally, when we map a texture onto a plane (for example), depending on the texture, it can look quite flat. We might increase the textured look of the object with bump maps or normal maps, however, the geometry is still flat...the texturing, a simulation.

On the other hand, if we have a displacement map for our texture, then we can subdivide the original object and apply the displacement map. This will actually alter the geometry of the object and therefore, looks much more realistic. [Note: When using a bump/normal map, the shadows cast from the object are still the exact shape of the object. A sphere with bump/normal map will cast a circular/oval shadow with no alterations where the texture of the sphere is concerned. With the displacement map, there will be accurate shadows cast. In the above example, the sphere could be casting a very different shadow, depending on the displacement map.]


Below is a plane with Texture and Normal map applied...



Below is the same plane with Texture and Displacement map applied... (exaggerated for obvious effect)



Below is a cube with repetitive brick Texture and Normal map...



Below is the same cube, but with Displacement instead of Normal map... (slightly exaggerated to show effect)



So...what do you need in order to use Displacement Maps?

Well, first, the map. [Some texture libraries also have Displacement maps for their textures, so they're worth picking up at the same time.]

Second, your object will likely need to be subdivided considerably (to give it a fine enough area to displace). [I usually subdivide and set it to "10" and then subdivide once more as the starting point.]

Then, you must add a texture channel and select your map image. Uncheck Color influence and check Displace and season the amount to taste.

Note: You can also create your own Displacement maps in Xara! Use grayscale and make white the closest to you and black, the furthest. {Frances, I just know you'd be able to use this idea for a cool effect.}

Here is (a converted jpg of) the displacement map used for the 2nd image above...



Have fun!

James

[ODdOnLifeItself]

Displacement maps work best with a bit of smooth transitioning. (blurring a bit sometimes helps this)

However; below, I just took a simple contour from our favorite graphics program, Designer Pro 7, and used it as a Displacement map applied to a simple plane. (so, technically, NO ADDITIONAL MODELING)



Below you can see the simple plane with various levels of Displacement (as shown in the graphic filename)...







Or, even negative displacements...



Have fun!

James

[ODdOnLifeItself]

Here is the same idea, but applied to a sphere. (remember, there was no additional modeling... only a sphere with a texture channel applied)





James

[guyke]

A while ago, I posted this picture - the two balls in front are done with displacement, the yellow one positive and the green one a negative displacement.



James, you commented you liked the other two better

[ODdOnLifeItself]

Hello Guy,

Re: "James, you commented you liked the other two better."

Which is not to say that I didn't like all of them. [pardon the double negative]

Here is another example... a field of rocks.

The first is the rock plane with bump map: (not bad, but too flat)



And now, the same rock plane but with displacement map: (much better, anything but flat)



Though a comparison could be made, there's really no comparison.

You can see in this "rock room" that shows the same texture/displacement from various angles, that the texture really is 3-dimensional. ie. the displacement map made it come alive



Peace

James

[ODdOnLifeItself]

Here is a (surely recognizable) Xara shape that was used "as is" as a displacement map.

Think how long it would take to model it as compared to the 10 mins it took in Xara and Blender to accomplish basically the same thing...



Peace

James