PointLight attenuation

andreasplesch · November 5, 2021, 1:14am

I am looking for PointLight falloff for standard (phong) material, and could not find much in the doc.

BabylonJS/Babylon.js/blob/5e6321d887637877d8b28b417410abbbeb651c6e/src/Shaders/ShadersInclude/lightsFragmentFunctions.fx#L22

    
      
          

          lightingInfo computeLighting(vec3 viewDirectionW, vec3 vNormal, vec4 lightData, vec3 diffuseColor, vec3 specularColor, float range, float glossiness) {

          	lightingInfo result;

          

          	vec3 lightVectorW;

          	float attenuation = 1.0;

          	if (lightData.w == 0.)

          	{

          		vec3 direction = lightData.xyz - vPositionW;

          

          		attenuation = max(0., 1.0 - length(direction) / range);

          		lightVectorW = normalize(direction);

          	}

          	else

          	{

          		lightVectorW = normalize(-lightData.xyz);

          	}

          

          	// diffuse

          	float ndl = max(0., dot(vNormal, lightVectorW));

          #ifdef NDOTL

has

attenuation = max(0., 1.0 - length(direction) / range);

eg. linear falloff with distance relative to range, and 0 beyond range.

Am I looking at the correct place ?

sebavan · November 5, 2021, 11:10am

yup this is exactly it for the standard material.

Topic		Replies	Views
Light Illumination Modes Questions	5	1749	October 16, 2023
Questions about .babylon file conventions Questions	4	290	February 20, 2020
Changing Light Falloff Physics Scale Questions lighting	3	726	November 17, 2021
Disabling specific light, or light type for a specific material/mesh Questions lighting , material	2	933	May 18, 2021
Surface color based on normals not working Questions	8	560	April 7, 2020

PointLight attenuation

Related Topics