Topology

When referring to computer graphics, 3d models and the like, topology is the wireframe of a given object. The wireframe is comprised of all the vertices (where lines meet to form a point), edges (the lines made up of two connects vertives) and from that information the faces can be made (generally have 2-3 connected edges per face). Now, as I pointed out in a previous blog I said that optimization was immportant for computer graphics. Today, I will go over "proper" topology.

Proper Topology?

Proper topology is the arrangement of the wireframe so that enough detail is present in the model while also keeping the polygon (faces) count to a manageable number (as low as possible while keeping necessary detail). In animation, proper topology goes one step further because it allows the model to deform more naturally when moving. (Bad topology example) (Good topology example)

Of course, there are no guides to proper topology for every single object that can be created but there is often discussion of maintaining edge flows/loops which are ringes of vertices/edges that can circle features of models. Human faces has more documentation for this and typically have the similar edge loops. This doesn't mean edge loops are not applicable to other models. See a few edgeflows in the Purple Page Eater. Even though he lacks a nose and a second eye, I still tried to keep edgeloops around his mouth and eyeball as seen in human facial wireframes.

Controling Topology

As I have been learning, these are some common methods used when dealing with topology in meshes.

1. Edgeflows, as stated previously, these are flows of vertices/edges that can circle areas but can terminate early just forming a line. The purpose of this is to provide more natural deformation. Notice here, that the loops around the eyes follow the muscles under the skin.

2. Poles, or where 3 or 5 edgeflows meet to terminate. These are general places where no animation occurs or where the mesh naturally crinkles as seen in this image.

3. Tri's (when still working with topology). These are basically triangles and often used to terminate edgeflows they tend to be hidden, like behind ears. The purpose of these is to preserve polygon count and often are used instead of adding an extra edgeloop that would create many more quads (square faces). In short, having 1 tri and is better than adding 8 or more quads. But note, tris are still used and seem to be a finalizing process, particularly in games (game model example).

Conclusion

To surmise, having proper topology is a good thing for the computer (less render time!) and animation (as well as some other processes like UV mappning). However, this adds anothing layer for me and others to think about when creating 3D models.

Interested in this topic? Then go here! He does a fairly good job in explaing the subject, I even used some of his images as reference.He also mentions a few workflows.

Faking 3d

One important aspect to 3D art is optimization. What I mean by this is that, if you make something appear the same or similiar to a more detailed object then that greatly decreases rendering/computing time. This is certainly paramount in video games since the computer must make calculations on the fly but still important in movies because it cost money that is usually determined by rendering time. Without further ado, I will briefly introduce one method to "Faking It."

Normal Mapping

To surmise what normal mapping is, it is basically a texture image that tells how light should effect the object to simulate bumps, dents and other details. My emphasis is on texture because the deficient way to create surface details is to actually model them out using more polygons. Again, the key here is optimization, adding more polys tends to be more taxing on the computer as opposed to a simple texture image that is wrapped around an object. Moving onward, here is an example I made both the outcome and the actual sphere model I used without the normal maps. The illusion to the ripples on the sphere is created through a normal map instead of polygons allowing this image to be created in relatively no time at all!

These were created in blender, if you wanted to use blender to make your own, click here! (Assuming you have some knowledge of blender)

Short Intro of myself

For the past couple months while working with the College of Arts and Sciences I have been doing 3D animation and some 2D artwork.  This blog will be specifically discussing my 3D endeavors in Blender.

Onto the 3D

To start, I will be using a 3D text model I made for an A&S Wired background. What you see in the picture is an optimized representation of the object and its material for easy editing purposes. That means, when the scene is rendered its appearance will be drastically different. My case and point. You will notice that its just an outline and this is because of its material and lack of light. In short, material means its shine, color, transparency, mirror, etc. will be shown when rendered. In this case, my object is emitting a glow around its contour and is transparent. With no light source, you will only see its glowing contour when rendered. If I were to simply add a light source that would be rather boring, so I want to fiddle around with particle effects to make the text appear in a more interesting way.

One way blender handles particles is by emitting them from the faces of a mesh or a 3D object (a plane in this scenario). Leaving it as the default particles means they will appear as fireflys that are visible even without light and give off their own light. I do not want the particles to be seen floating from bottom to the top of the screen so I will be deviating from the default settings. Instead, I replace the normal halo (fire flys) particles with light source objects. I do this because they do not have a structure that is directly seen but still give off light that will affect the Wired text.

With everything in place, I now start rendering or the “magic” whereby the computer can take long periods of time ray tracing each frame at 24 frames per second over an 8 second period.  At such a low resolution (and other settings) I was able to get the render time down to 1 minute for this test render. (First Animation)

It’s way too fast, after a few more test renders and modifications to speed I was able to get this render which took about 10 minutes to render at the same resolution but to 16 seconds. (Final animation)

This result was closer to my liking. Perhaps too slow in the first few seconds but rendering can try your patience. Despite the loading, the outcome is worth the wait. See ya next time!

Note: I was having trouble getting my images to appear and so I apologize for having them hyperlinked.