Basic Game Art Concepts - Game Character Creation with Blender and Unity - page 15

A fourth factor in how many polygons something can have—a factor so important that
it deserves its own paragraph—is the power of the engine and console. Gears of War was
built on the Unreal engine, which in its various forms has pushed the envelope on visual
quality in video games. Additionally, the game is on the Xbox 360, a modern home con-
sole. Not every engine or console is as powerful as those for commercial games, however.
It is important to know that models like the one for Marcus may be difficult to work with
if you are not launching onto similar hardware.
Since Unity is capable of delivering content both to powerful modern consoles and to
less powerful mobile devices, it is important to practice using lower poly counts. In ear-
lier model iPhones, for example, a budget of 7,000 visible polygons on the screen was the
maximum for optimum performance. This is an incredibly light number compared to the
hundreds of thousands possible on consoles. This might require even main characters to
be around 1,000 to 2,000 polygons. Link from The Legend of Zelda: Twilight Princess on
the Wii, on the other hand, is about 6,900 polys and is shown among some very detailed
environments. Therefore, the polygon budget for Wii games is much higher than on some
mobile platforms, though not as high as high-definition consoles.
Model Topology
In addition to polygon count, it is incredibly important to note that the polygons should
be arranged properly on a model so they can animate smoothly. The arrangement of poly-
gons on a 3D model is commonly called topology , and is something that many new 3D
artists struggle with.
Novices whose background is in other forms of art where the final product is key—
especially those who have worked in animation with smoothing modifiers—often model
wildly, trying to get the best outcome possible on their characters without giving con-
sideration to topology. When they switch out of smooth mode, they are often shocked to
find that their polygons are overlapping one another and entire body parts are awkwardly
sticking up through each other. In order for your model to properly function, you must
lay out the topology properly. Here are the three most important rules to follow:
• Make sure that all polygons are quads (polygons with four sides).
• Joints on extremities should have at least three edge loops.
• Lay out facial geometry with loops around openings (Figure 1.17).
You'll practice this later in the topic, but for now, keep in mind that quads are what
3D animation programs know how to properly distort for animation. Triangles (polygons
with three vertices) are possible in Blender but will not deform properly when moving.
Any polygon with more than four vertices is known as an ngon, with “n” represent-
ing a variable number. You should avoid these altogether when modeling if you want to