1. Textures and Maps MCC 1013- Computer Modelling Trimester 1 – 2015/2016

2. Learning Objective Materials and surfaces Understanding textures and mapping © Juhanita 2015

3. Materials and surfaces In the real world, materials or elements have three natural phases: Solid Liquid Gas Each phase has unique properties that define it, and characterize its look. © Juhanita 2015

4. Surfaces in all phases share common characteristics or properties: colour Shininess Bumpiness Transparency etc Materials are also known as shaders Materials and surfaces © Juhanita 2015

5. In the real world, materials have surfaces that determine how much light the material absorbs or reflects. In 3D, materials are defined by several groups of visual properties, like colour, shininess, and transparency, which you can mimic real world or fantasy surfaces. Visual components of materials © Juhanita 2015

6. Visual components of materials Colour Bumpiness Shininess – specular highlights, anisotropic highlights Transparency Luminosity – self-illumination © Juhanita 2015

7. An object’s rendered appearance is influence by three different sources of colour and value: Ambient – is the hue an object reflects if it’s not directly illuminated by light source (shadow areas) Diffuse – hue assigned to the object Specular – hue of any highlights that appear on the object Colour and Value of Objects © Juhanita 2015

8. Colour in 3D is represented in: RGB(Red, Green, Blue) or HSV(Hue, Saturation, Value) values to define a surface colour or you can map a texture or file texture to a material. Colour and Value of Objects © Juhanita 2015

9. © mcyuen 2008 If a surface is shiny it can have highlights, or hard reflectivity values. The less shiny it is, the softer is its reflectivity and less it will reflect other surfaces. Shininess © Juhanita 2015

10. © mcyuen 2008 These are not round highlights – the specular highlights so far commonly seen. Anisotropic are ecliptical, directional types of highlights seen probably in hair, velvet, brushed metal and the data side of the CD. Anisotropic Highlights © Juhanita 2015

11. Bumpiness A surface can appear bumpy or it actually can have displacements in its surface values. Visual components & materials © Juhanita 2015

13. cyuen 2008© m© m Transparency A surface can be transparent or opaque. When ray-tracing a transparent surface, light rays that penetrate the surface bend, and the light is refracted. Visual components & materials © Juhanita 2015

14. Self-illumination Sometimes when light strikes a surface, the surface appears to be lit from within, or it appears to have a glowing halo. Visual components & materials © Juhanita 2015

15. Texture mapping is a method, pioneered by Edwin Catmull, of adding detail, surface texture, or colour to a computer-generated graphics or 3D models. A texture map is applied (mapped) to the surface of a shape. Texture mapping © Juhanita 2015

16. The process of assigning material attributes to an object. Mapping © Juhanita 2015

17. Before textures are applied, all objects in a 3d package have a default plastic appearance, usually gray or in some range of colours. Mapping enables the user to give the object a specific colour, adjust whether it’s shiny or matte, and apply a pattern and so on. Mapping © Juhanita 2015

19. Map Channels © Juhanita 2015

20. The common ones are: Diffuse maps Bump maps Reflection maps Opacity maps Maps © Juhanita 2015

21. Simply said, these maps are generally in Colour and are used to alter the object’s colouraway from that defined by the coloursetting into a pattern or image. Diffuse Map © Juhanita 2015

22. Bump maps vary the surface roughnness by manipulating the object’s normals according to a grayscale image. Bump maps does not distort the mesh, they adjust the normals’ vector angle. These maps use the light and dark of the map to determine a section’s protrusion, flush and indent. Bump maps are often used in games assets where details are put on the map rather than on the mesh. Bump Map © Juhanita 2015

23. These are often known as ‘environment mapping’ because reflection maps are used to provide an “environment” for the object to “reflect”. Reflection Map © Juhanita 2015

24. Opacity maps are grayscale images that override the material’s transparency settings and allow for an object to vary from opaque to transparent. Similarly, an opacity map uses the grayscale values to control the transparency limits. An example is putting holes in an object without resorting to mesh changes. Opacity Map © Juhanita 2015

26. Mapping coordinates are a set of coordinates that specify location, orientation and scale of any textures applied to an object. Similar to the function of coordinates in 3d space, mapping coordinates can affect the map’s orientation accurately and effectively. Mapping coordinates © Juhanita 2015

27. The mesh coordinate system for mapping is called the UV coordinate system. UVW coordinates can be positioned to provide much more accurate positioning. Mapping coordinates UVW © Juhanita 2015

28. There are 4 common mapping types for mapping projections: Planar Cylindrical Spherical Cubic Mapping coordinates UVW © Juhanita 2015

29. Planar projections are flat, useful for mapping objects like walls, doors or book. Planar Projection © Juhanita 2015

31. Cylindrical projections wrap the image around on of the objects’ axes. This may result in a seam which can easily be corrected with some tiling measures. Cylindrical Projection © Juhanita 2015

33. Spherical projections wrap the image around the object in a cylindrical manner and then pinch the top and bottom closed to surround it. Spherical Projection © Juhanita 2015

35. Cubic projections also known as box coordinates map from six different directions. Cubic Projection © Juhanita 2015

36. There are several different shaders. Some are named for what they do; others are named for their creators. Shading Modes © Juhanita 2015

38. Texture mapping is a method, of adding detail, surface texture, or colour to a computer-generated graphic or 3D model to mimic real world or fantasy surface attributes of materials. Lesson Summary © Juhanita 2015

39. http://www.3dlinks.com/Links.cfm?http://www.3dlinks.com/Links.cfm?categoryid=13&subcategor yid=105&subsubcategoryid=47 http://www.mobilefish.com/tutorials/3dsmax/3dsmax_quickgui de_materials.html Principles of Three-Dimensional Computer Animation, Michael O’Rouke 3d graphics & Animation, Mark Giambruno http://www.mayang.com/textures http://www.3dtotal.com/tutorials/ http://highend3d.com/3dsmax/ Referrences © Juhanita 2015

40. Thank You! And A Very Special Thank You to Ms May Chan for The Content of This Lecture.