Unity Lighting Models

Unity Lighting Models. There are two builtin lighting models Lambert for diffuse lighting and BlinnPhong for specular lighting The Lightingcginc file inside Unity defines these models (Windows /Data/CGIncludes/Lightingcginc macOS /Applications/Unity/Unityapp/Contents/CGIncludes/Lightingcginc ).

Introduction to Lighting and Rendering 1 If you are using Unity 20193 or above click here Modern game lighting makes extensive use of ‘global illumination’ Choosing a Lighting Technique 1 Broadly speaking lighting in Unity can be considered as either ‘realtime’ or ‘precomputed’ in some way and both techniques can be used in combination to create immersive scene lighting The Precompute Process 0 In Unity precomputed lighting is calculated in the background either as an automatic process or it is initiated manually Choosing a Rendering Path 0 Unity supports a number of rendering techniques or ‘paths’ An important early decision which needs to be made when starting a project is which path to use.

Unity Manual: Custom lighting models in Surface Shaders

Lighting Models In Unity Jordan Stevens Lighting Models are methods/algorithms used to determine the light at the surface of a model There are many varying methods of computing lighting with shaders Artists and programmers choose them depending on the level of realism/stylization/performance implications of the model.

Lighting Models In Unity Jordan Stevens

Create A New ShaderHow It WorksConclusionStart by carrying out the following steps 1 Create a new shader and give it a name (SimpleLambert) 2 Create a new material give it a name (SimpleLambertMat) and assign thenew shader to its shaderproperty 3 Then create a sphere object place it roughly in the center of the sceneand attach the new material to it 4 Finally create a directional light to cast some light on your object if oneisn’t created already 5 When your assets have been set up in Unity you should have a scene thatresembles the following screenshot Achieving the Lambertian Reflectance The Lambertian reflectance canbe achieved with the following changes to the shader Begin by replacing theshader’s Properties block with the following  Since you are removing all of the other properties removethe _Glossiness _Metallic and _Colordeclarations insidethe SubShader section Change the #pragma directive of the shader so that it uses your custom lightingmodel instead of Standard If you try to run the scrip SimpleLambert forces Cg to look for a function called LightingSimpleLambert()Note the Lighting at the beginning which is omitted in the directive The Lighting function takes three parameters the surface output (which containsphysical properties such as the albedo and transparency) the direction thelight is coming from and its attenuation According to the Lambertian reflectance the amount of light a surface reflectsdepends on the angle between the incident light and the surface normal If youhave played pool or billiards you may surely be familiar with this concept thedirection of a ball depends on its incident angle against the wall If you hit a wall at a 90degree angle the ball will come back at you if youhit it with a very low angle its direction will be mostly unchanged TheLambertian model makes the same assumption if the light hits a triangle at a90degree angle all the light gets reflected back The lower the angle theless light is reflected back to you This If you found this article interesting you can exploreUnity 2018 Shaders and Effects Cookbook Third Editionto bring realism to your games by mastering postprocessing effects and advancedshading techniques in Unity 2018 Since their introduction to Unity shadershave been seen as notoriously difficult to understand and implement in gamesUnity 2018 Shaders and Effects Cookbook Third Editionchanges that by giving you a recipebased guide to creating shaders using Unity.