UFCEKT-20-33D Modelling and Animation 3D Modelling & Animation Materials and Textures Maps.

UFCEKT-20-33D Modelling and Animation

3D Modelling & Animation

Materials and Textures Maps


Agenda

Purpose of Materials and Texture Maps Material Types and Attributes Texture Maps The Hypershade Classic Shading Algorithms


Materials and Texture Maps

Geometry is only one aspect of creating a realistic object or environment Apply materials and textures is an essential aspect of creating realism in a

scene Using materials and textures can create attributes such as colour, transparency,

and shininess of an object. Materials are referred to as shaders in Maya Materials control how the light interacts with the an object’s surface Material nodes may be combined to create a shading group Shading group applied to an object to achieve desired surface characteristic Textures are image files that can act as input nodes for the various material

attributes including a relief texture node that defines its surface as a bump map Properties of materials and texture nodes can be viewed in an interface called

the Hypershade


Materials Types

Anisotropic. This material has elliptical specula highlights Blinn. Provides soft circular highlights and is good for metallic surfaces Lambert. This material has no highlights and is useful for cloth and non-

reflective surfaces Layered Shader. Combines several shaders into one single shading object Phong. Provides hard circular highlight and is good for glass surfaces Phong E. Similar to Phong, but optimised to render faster Shading Map. This material allows for colour changes to the rendering which

provides cartoon shading Surface Shader. Provides a connection to a surface material attributes Used Background. Allows for adjustment and control of an objects shadows and

reflections


Materials - Basics

Anisotropic - surfaces with micro faceted grooves and specula highlights, e.g hair stain and CDs have anisotropic highlights

Lambert - matt surfaces - no specula highlights good for matt surfaces - e.g paper

Blinn - good specula highlights - Good for glass and metal surfaces

Phong - good specula highlights - Good for plastic surfaces


Classic Shading Algorithms

Gouraud Shading, named after Henri Gouraud, is a method to simulate the differing effects of light and color across the surface of an object. Gouraud shading is used to achieve smooth lighting on low-polygon surfaces without the heavy computational requirements of calculating lighting for each pixel. Gouraud first published the technique in 1971.

Gouraud Shading


Classic Shading Algorithms

The Phong interpolation method works better than Gouraud shading when applied to the Phong reflection model or to any reflection model that has small specula highlights.

This methods were developed by Bui Tuong Phong, who published them in his 1973 Ph.D Thesis at the University of Utah.

Phong Shading


Texture Maps

Image files can be ‘mapped’ to geometry to provide authentic surface detail and characteristics.

Mapping is controllable through the attribute editor for placing textures on objects.

Texture maps are also useful for providing a look for an object where a high level of detail is not required for an objects geometry - brick walls, guitar fret board for example.

Texture maps can also be used to replace distant geometry where level of detail (LOD) is such that it permits the substitution of the geometry with a textured primitive object.

Texture maps can themselves be combined with other shader nodes to provide layered texturing characteristics to achieve the desired modelling effect


U V Mapping

UV Mapping is the process of mapping a 2D coordinate grid to a 3D model the U maps in the x plane and the V maps to the y plane

The 2D grid is associated with a corresponding image file to place on the model

A single image can contain several component images which ‘map’ to regions on the 3D model

Maya provides facilities to create a Photoshop .psd within the Maya environment which can then be edited within Photoshop to create the desired image map and then view the updated image inside Maya

UV mapping is often used within games to apply the artwork to polygon geometry within the game environment


UV Texture Mapping Example


Environment Mapping

Environment mapping is where an image is used to map onto a surface to give the effect of the surface reflecting the surrounding environment.

Image to be used as an environment map


Environment Mapping

surface

image to use as environment map


Environment Mapping Result

Renderer: Maya SoftwareFormat: .tga 1024 x 768


Environment Mapping Result

Renderer: Mental RayFormat:.tga 1024 x 768

UFCEKT-20-33D Modelling and Animation 3D Modelling & Animation Materials and Textures Maps.

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Transcript of UFCEKT-20-33D Modelling and Animation 3D Modelling & Animation Materials and Textures Maps.