Need advice on turning a 2D image into a 3D model

Question

As promised post #2 for today, all about a particular piece of furniture that i am struggling with.

as you can see from the following picture there is a sign in on the back wall of the club that reads "Fatal Addictions"

At present that is just a flat image texture on a plane.

What I am TRYING (and failing) to create is the blood spatter in 3D. not terribly prominent, but the idea is that the blood is a molded plastic relief which is maybe 6 inches deep in the real world with a backing box behind it, which would contain a light which would illuminate the blood spatter from behind (the blood being made of a plastic or glass type material).

I want it to look exactly like the original logo which I made in Photoshop for the original second life version, just all swanky and 3D and pretty

I have images of all the components (The lettering and syringe are going to be modeled separately and the whole thing put together in layers)

here is the .png file of the blood spatter behind it. I am sure there must be a way to turn something 2D into something 3D in blender, but I have yet to either find a video tutorial, or stumble across how to do it myself and it is getting quite frustrating.

Anyone with ideas or offers of help please get in touch. it would be greatly appreciated.

Answer 1

I started off by adding the image you posted as a material texture on a plane that was UV un-wrapped using the default option that shows up at the top of the list which is called Unwrap.

Then I unchecked the Color channel for this texture and used the Normal Channel instead. Sometimes when adding a color or greyscale texture as a bump map will cause the effect to look inverted so if this happens then you can use a value of -1.0 instead of 1.0

The image at the left is the Tangent map I baked that captures the bump map as surface normals.

There was some noise in the baked image so I saved it and opened it with GIMP and blurred the tangent map using Gaussian Blur set to 10 pixels. Now I reloaded this tangent map into Blender and replaced the image that you posted and changed the Mapping Type to Normal Map-> Tangent. I also changed the -1.0 to +1.0 for the Normal value.

Here is now what it looks like after the blur.

For simple planes like this, it's fine to blur the normal map but for complex objects this will not work well since the seams will become immediately obvious even for a very subtle blur.

One thing I forgot to mention is that normal maps that are saved as .png are in sRGB format and if you plan to use Cycles then they should be set to non-color format. It doesn't seem to matter for Blender Internal View-port drawing.