Graphics Graphics Korea University cgvr.korea.ac.kr Lighting, Fogging, Alpha Blending & Progressive Meshes Byeong-Seon Jeong

CGVR Graphics Korea University cgvr.korea.ac.kr Contents Lighting Fogging Alpha Blending Progressive Meshes Demo

CGVR Graphics Korea University cgvr.korea.ac.kr Lighting Ambient Light is effectively everywhere in a scene a general level of light that fills an entire scene has no position or direction, only color and intensity Direct Light Point  give off light equally in all directions  have color and position within a scene, but no single direction

CGVR Graphics Korea University cgvr.korea.ac.kr Lighting(directional) Directional  emit parallel light  have only color and direction, not position  a light source at near infinite distance, such as the sun

CGVR Graphics Korea University cgvr.korea.ac.kr Lighting(spot) Spot  is made up of a bright inner cone and a larger outer cone  have color, position, and direction in which they emit light

CGVR Graphics Korea University cgvr.korea.ac.kr Lighting(global illumination) Global Illumination Formula

CGVR Graphics Korea University cgvr.korea.ac.kr Lighting(ambient) Lighting Model Ambient  provides constant lighting for a scene  lights all object vertices the same  Formula

CGVR Graphics Korea University cgvr.korea.ac.kr Lighting(ambient)  Scene

CGVR Graphics Korea University cgvr.korea.ac.kr Lighting(ambient) Source Code

CGVR Graphics Korea University cgvr.korea.ac.kr Lighting(diffuse) Diffuse  comes from one direction  is scattered equally in all directions once it hits a surface  Formula

CGVR Graphics Korea University cgvr.korea.ac.kr Lighting(diffuse)  Attenuation Factor

CGVR Graphics Korea University cgvr.korea.ac.kr Lighting(diffuse)  Spotlight Factor

CGVR Graphics Korea University cgvr.korea.ac.kr Lighting(diffuse)  Scene

CGVR Graphics Korea University cgvr.korea.ac.kr Lighting(diffuse)  Source Code

CGVR Graphics Korea University cgvr.korea.ac.kr Lighting(specular) Specular  comes from a particular direction  tends to bounce off the surface in a preferred direction  Shiny metal, plastic  Formula

CGVR Graphics Korea University cgvr.korea.ac.kr Lighting(specular)  Scene

CGVR Graphics Korea University cgvr.korea.ac.kr Lighting(specular)  Source Code

CGVR Graphics Korea University cgvr.korea.ac.kr Lighting(emissive) Emissive  is emitted by an object  Glow  Formula

CGVR Graphics Korea University cgvr.korea.ac.kr Lighting(emissive)  Scene

CGVR Graphics Korea University cgvr.korea.ac.kr Lighting(emissive)  Source Code

CGVR Graphics Korea University cgvr.korea.ac.kr Fogging Adding fog to a 3-D scene can enhance realism provide ambiance or set a mood, and obscure artifacts Formula

CGVR Graphics Korea University cgvr.korea.ac.kr Fogging(factors) Factors  Linear

CGVR Graphics Korea University cgvr.korea.ac.kr Fogging(factors)  Exp

CGVR Graphics Korea University cgvr.korea.ac.kr Fogging(factors)  Exp2

CGVR Graphics Korea University cgvr.korea.ac.kr Fogging(graph) The Illumination graph of the formula

CGVR Graphics Korea University cgvr.korea.ac.kr Fogging(scene) Scene

CGVR Graphics Korea University cgvr.korea.ac.kr Fogging(source code) Source code

CGVR Graphics Korea University cgvr.korea.ac.kr Alpha Blending combines the color value of the processed polygon pixel with the pixel already stored in the frame buffer Formula

CGVR Graphics Korea University cgvr.korea.ac.kr Alpha Blending(scene) Scene

CGVR Graphics Korea University cgvr.korea.ac.kr Alpha Blending(source code) Source Code

CGVR Graphics Korea University cgvr.korea.ac.kr Progressive Meshes A progressive mesh is one in which the vertex information is stored internally in a special tree that can be accessed to render the mesh with any number of vertices. This procedure is fast, so progressive meshes are ideal for level-of-detail scenarios, where objects in the distance are rendered with fewer polygons.

CGVR Graphics Korea University cgvr.korea.ac.kr Progressive Meshes(diagram) Progressive Mesh Flow Diagram Graphic files Ex. *.3DS, *.ASE etc Dynamic LOD User input Ex: Distance *.X file load Material & Texture setup Progressive Mesh creation Progressive Mesh Level Control Rendering Initialization Update frame

CGVR Graphics Korea University cgvr.korea.ac.kr Progressive Meshes(scene) Scene

CGVR Graphics Korea University cgvr.korea.ac.kr Demo