Introducing To 3D Modeling George Atanasov Telerik Corporation

 3D Modeling process  Representing any 3 dimensional surface  Automatic or Manual 2

 The product is called 3D model  3D model can be:  Rendered to 2D image  Printed to realistic object with 3D printer  Used in 3D games with real-time rendering 3

 Vector design is better for industrial goals  Hands of the Craftsman vs. CPU Lathe 4

 Polyhedral object  Best for games and physical simulations 5

 Polygon mesh sub-object level  Vertex  Edge  Face  Polygon 6

 Why Mesh is better for game development?  More calculations == less FPS  Nowadays GPU’s are designed to perform faster with VBO’s (Vertex Buffer Objects)  Mesh objects can be easy represented in VBO  The absolute accuracy of the objects is not basic goal in the Games  In game developing the basic goal is to create best possible representation of object with by less possible resources 7

 Three dimensional coordinate system  Represents uniquely all the points in it by three parameters – values for each axis  Contain sub-coordinate systems  Each object has his own local coordinate system local coordinate system 8

Explaining High-Poly Design

 We can understand the idea of high-poly modeling just by its name  The more triangles in the mesh, the more detailed the object is  It is 10

Explaining Low-Poly Design

 Low poly mesh is a mesh which has small amount of polygons  Commonly used in real-time applications  In theory polygons can have infinite number of sides, but in 3D graphics they are broken down into triangles 12

 Why we need to create low-poly models when there is so many smooth modifiers?  In general the more triangles in a mesh the more  detailed the object is  computationally intensive it is to display  To decrease render time it is better to use low poly models 13

 A combination of game engine and the computer being used defines the polygon budget  It is equal to the number of polygons which can appear in a scene and still be rendered with acceptable frame rate  It vary depending on the  speed of the render engine  the amount of polygons  The speed of the hardware 14

 There is no defined threshold for a mesh to be low poly  This term is relative and its definition depends on other factors:  The time the meshes were designed and for what  The detail required in the final mesh  The shape and properties of the object 15

 Super Mario 2 – 1996  In 1996 rendering an objects created by 240 polygons was a huge success  All the environment is created by textured extremely low polygon objects  Crysis 2 – 2011  At 2011 rendering objects created by polygons is not a big deal  The environment is created by averagely resolute objects 16

 Low poly objects does not always has to look bad  You can “lie” the viewer that the object has better resolution with techniques such as  Normal mapping  Bump mapping  Etc. 17

Smoothing techniques

 There is many methods to create a smooth objects  Normal smoothing  Mesh smoothing  Etc.  It is important to understand haw to use each one of them  You have to pick the best for your goals 19

 Normal smoothing affects only the way that the light is reflected by the objects surface  That is better for games, because the triangle count stays the same 20  Ends of the object remain edgy  Performs better on dark colors

 Mesh smoothing affects directly the geometry of the object  Can be used many times on the same objects  Iteration value  With each iteration increase, the resolution of the object increases by square 21

Understanding Lightning in 3D

 Modeling the 3D object is just a little part of the whole design process  The light makes the object to look as 3D object 23

 For full realistic light simulation you would need a “NASA” computer  The lighting in 3D graphics is not exact representation of the real light  In most 3D engines the light appearance is decayed to separate effects independent each other 24

 The light is composed by several abstract components  Diffuse, Ambient, Specular, Emissive, Reflection, Refraction  Each light component can has its own color  It is important to understand how to deal with each type of them  And it is more than important to understand how the real light affects the objects 25

 When sun ray hit an object it reflects from it  The ambient light is the emission of all light sources  The result is averagely brightening whole object  3D object with only ambient light channel applied to it looks 2D 26

 Diffuse light represents a directional light cast by a light source  It can be explained as a light from light bulb placed on specific location in the space  A diffuse light of red color, coming from the left of a black object defining its 3D shape 27

 For more realistic result we can apply the both diffuse and ambient light channels  The diffuse light represents a light from a light bulb and flashing the front side of the object  The ambient light brightens the entire object 28

 The specular light channel represents the brightest area of the object (the highlight area)  The position and the amount of specular highlight is depending on  Viewers position  The angle between the viewer and the source 29

 Emissive light is working a little different than the explained before types of lights  It is responsible for the object material ability to absorb or reflect light  Below is the result of object emitting green light with red light source applied 30

 The use of reflections helps to create more realistic objects  Remember... You wont see the reflection effect if you don’t have another objects to reflect  Reflection looks better on round objects  Do not overdo with the reflection effect reflection effect  Reflection mapping saves time 31

 The refraction property defines how much light goes through the object  In simple language it controls the opacity of the object  Refraction color # == full opacity  Refraction color #FFFFFF == full transparency 32

Learn Texturing Essentials

 Textures are just simple raster pictures  JPEG  PNG  TGA  GIF  TIFF  Widely used in 3D game modeling 34

 If you are developing a car racing game you do not need to model all the details on the buildings behind  By texturing your object you can add a lot of details on the model without adding any more resolution to it  For example you can use a texture of window instead of modeling it 35

 There is several ways to texturize an object  Which one is better depends on the object which is going to be texturized  In game developing process the basic texturing methods are  UVW Mapping  Tiling  UVW Unwrapping 36

 Tiling is another trick which saves a lot of resources  To understand it, imagine that you have to represent the facade of a huge building by texturing  The idiotic way is to draw a huge texture with a lot and the same windows in it  The right way is to draw a texture with only one window on it and multiply it 37

 Creating details with textures instead of polygons saves render time  Do not flood your 3D scene with huge amount of textures  Do not use bigger textures than you need  Manage balance between quality and size  When it is possible use texture modulation 38

 Useful for level editing (creating environment)  You want to model brown one and the same roof tiles, but in different colors  Use white (or bright) roof tile texture and modulate it with the color of its object  You can create many different looking models with the use of one and the same resource 39

 OK… We have to create a metal fence  But how many polygons we need?  First way is to create it as a polygon mesh  polygons for 1 meter wide fence ?!?  The trick to do that is to use a texture of metal fence with transparency at the empty spaces  2 polygons and the result looks the same 40

 Projects a texture map to 3D object  Assigns pixels of the image on the polygons  Allows you to texturize more complex shapes 41

 A very useful technique for texturing game characters and other complex objects 42

What Software To Use

 Your goals are ?  Making super cool 3D game models  Making very detailed models for commercials, magazine covers, movies, etc.  Making 3D models for an industrial goals  Level editing for games  You are learning 44

Questions?