Unit 69
For this unit I have to create one asset that is going to be a main feature of the game I am building for unit 18, it has to be below 8,000 trails, fully textured and have a high to low poly bake as well.
Before I start to design my assets model for unit 69, I decided to research about good topology, what is the correct topology for my model and what is not correct. Topology is the components that are connected and flow around the 3D objects, these are usual faces, edges and vertexes. As I’m making a game model I should optimised it to create a good silhouette, good edge loops for better deformation (mainly for characters) and for subdividing, extreme changes between surface normals (also known as vertex normals) and good UV seams. For good topology I want my model to be quads and little as possible triangles and avoid N-gons N-gons are shapes with more than four edges, these cannot be subdivided and would break the model when tried to be generated. N-Gons are also bad for games as well when put into a game engine as the engine tries to process the n-gon and puts more strain onto the graphics card and computer. The engine turns a quad into two triangles that it can render a N-gon will require more tingles and the more triangles the more time it takes for the engine to render causing a bottle neck known as lag or fps drops. Triangles are bad when trying to subdivide as it would not be able to subdivide the triangle and causes more errors Quads are more ideal as there are four edges and can connect easily to the next face, can be subdivided with out error and can be deformed with extra edges in the area e.g. bends or limbs References: http://blog.digitaltutors.com/ngons-triangles-bad/
Other type (manifold Surfaces) of bad topology I need to avoid to get good topology is: T-Vertices are when you have two edges connected and form a T-shape with the edges leaving a vertex, this can cause errors if not used correct. if a T-Vertices connects into a quad I can create an N-gon and won’t have edge flow and cause bad subdivision. Best used when the model edges are flowing around a corner and T-Vertices is connected to a triangle and this created a quad. But these should be avoided if possible. References: http://blog.turbosquid.com/2013/09/05/checkmate-pro-v2-specification-t-vertices/ Doubled faces usually caused by extruding twice and causes faces to overlap or when vertices / edges are target welded to other parts of the model and causes overlapping and double faces. Holes are usually created when faces have been deleted and existing faces have not been connected via vertex or edges as shown in the photos below. Reversed faces happen when the surface normals flip to show the black underside of the face and can be easily fixed by reserving the surface normals back. Unseen faces are internal faces that we forget to delete when connecting two parts of the mesh together via mirroring, extruding or combining Reference: https://accad.osu.edu/~sconroy/accad5002/notes_geo_problems.html Floating vertices are when an edge has been deleted and vertexes have been left and are not connected to any other edges. these cause errors when subdividing and texturing and can cause problems when imported into the game engine. T-vertices can also be classed as this as well. High-valence Vertex also known as poles is when 5 or more edges converge at a single vertexs, most commonly found when making a cylinder and the cap has all the edges going to one vertex. Having poles in a model will cause problems when applying a smooth or subdividing. Best way to get around this removing any poles and turn it into quads and tringles as show in the photos below, one photo with a pole and another with quads and triangles Now if add a smooth/subdivide to each of these, the pole will only subdivide so far while the quad model subdivided perfectly. These are all the different types of bad topology that I need to look out for when i am creating my model. Surface normals I also researched about surface normals so I could get soft and hard edges in my model. Every polygon includes information about how light will bounce of the face of the polygon, by changing the direction of the surface normals we can change how the light bounces of the surface creating face that look more soft or have hard crisp edge lines. Maya has lots of tools to change the surface normals, I will only be using two of these tools: mesh display > Hard edge and soft edge. In the photos below show a face with default surface normals and once that have been edited In the photos below show a model been effect by hard and soft edge
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1/16/2024 08:17:45 am
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