Monday, 17 March 2008

Creative Reading

Sometimes you just wish you could find that really useful resource from a source that is reliable, that is well designed, discusses creative issues in a professional way AND doesn't ask you to pay for it. The Adobe Magazine is one of those resources.


You can access it free at this address - http://www.adobe.com/products/adobemag/pastissues.html - and it includes a full archive right back to 1995.
I also read a plethora of other creative journals but this has to be one of the best of the free. What are you waiting for?

Saturday, 8 March 2008

Parallax Mapping

While we are on the subject of mapping images to 3D meshes, you might want to learn about parallax mapping.

Parallax mapping finally begins to overcome the problem with all the other mappings (texture, bump and normal), which is that they all look painted on and flat when viewed up close, especially at an angle.

That is because they are in effect painted on. Parallax mapping works by actually displacing the coordinates of the texture, so that bumps actually obscure dents as you move round in 3D space. Hoorah.


Comparison of mapping methods (Brown University, Rhode Island) click to enlarge.

Friday, 7 March 2008

Normal Mapping

Just a quickie tonight, I just had to tell you about this great tutorial I found for creating normal maps. A genius called Ryan Clarke is altruistic enough to share his technique free and for nothing on his site here >.

Why do I care? Basically as an interactive media blokey, I am interested in this latest method of adding detail and realism to games.

To begin with 3D games were made using very low res meshes and texture mapping. Bump mapping adds more realism by adding a little height and depth to a surface texture on the polygons - this is done using a grayscale image to represent the height of the bumps, (the lighter the pixel the higher the altitude etc.) but it still looks like blocks with textures. To remove the blockiness of the models you would expect to have to increase the number of polygons they are made up of. This is no good for games where the computer has to render 30+ fps on the fly. This is where normal maps help.

To really grasp this you need to know what a normal is >.

Normal mapping works on a similar principle to bump mapping in that it is essentially a graphic wrapped round a mesh, but it goes much further. Normal maps use an RGB image which instead of containing just height data in each pixel contains the X Y Z 3D orientation of the normal.

These then render much more realistically almost as though they were meshes themselves and have the added bonus of rendering faster. This allows PC's and games consoles to increase the apparent level of detail in the models without increasing the polygon count.

Normal mapping (above) compared to bump mapping (below) - images courtesy of Inagoni makers of a normal mapping plugin for Carrara.
Anyway, I just wanted to bring your attention to the fact that you can make your own normal maps quite easily using a torch, a digital camera, and some image editing software - take a peep >