Rasagar/Library/PackageCache/com.unity.render-pipelines.high-definition/Documentation~/convert-from-built-in-convert-lighting-and-shadows.md

Convert lighting and shadows

HDRP uses physical Light units to control the intensity of Lights. These units don't match the arbitrary units that the Built-in render pipeline uses.

For light intensity units, Directional Lights use Lux and all other Light types can use Lumen, Candela, EV, or simulate Lux at a certain distance.

To set up lighting in your HDRP Project:

1. To add the default sky Volume to your Scene and set up ambient lighting go to GameObject > Volume > Sky and Fog Global Volume.

2. Set the Environment Lighting to use this new sky:

   1. Open the Lighting window (menu: Window > Rendering > Lighting Settings).
   2. In the Environment tab, set the Profile property to the same Volume Profile that the Sky and Fog Global Volume uses.
   3. Set the Static Lighting Sky property to PhysicallyBasedSky.
   4. Optionally, if you don't want Unity to re-bake the Scene's lighting when you make the rest of the changes in this section, you can disable the Auto Generate checkbox at the bottom of the window.

3. Currently, the shadows are low quality. To increase the shadow quality:

   1. Create a new Global Volume GameObject (menu: GameObject > Volume > Global Volume) and name it Global Settings.

   2. To create a new Volume Profile for this Global Volume:

      1. Open the Global Volume's Inspector window and go to the Volume component.
      2. Go to Profile and select New.

   3. To add a Shadows override:

      1. Go to Add Override > Shadowing > Shadows.
      2. Enable Max Distance.
      3. Set Max Distance to 50.

4. Configure your Sun Light GameObject.

   1. Select your Light GameObject that represents the Sun in your Scene to view it in the Inspector.
   2. Go to Emmision and set the Intensity to 100000.
   3. Set Light Appearance to Color.
   4. Set Color to white.
   5. To see the sun in the sky, go to Shape and set Angular Diameter to 3.

5. The Scene is now over-exposed. To fix this:

   1. Select the Global Settings GameObject you created in step 3.
   2. Add an Exposure override to its Volume component (menu: Add Override > Exposure).
   3. Enable Mode and set it to Automatic.
   4. To refresh the exposure, go to the Scene view and enable Always Refresh.

   

6. HDRP supports colored light cookies, whereas the Built-in light cookies use a texture format that only contains alpha. To correct the Light cookie:

   1. In the Project window, select your Light cookie from your Assets folder.
   2. In the Inspector, change the import type from Cookie to Default.
   3. Set the Wrap Mode to Clamp.

7. Correct spot lights:

   1. In the Hierarchy, select a Spot Light and view the Light component in the Inspector.
   2. Go to Emission and set Intensity to 17000 Lumen to represent two 8500 Lumen light bulbs.
   3. In the Emission, select the More menu (⋮) and enable additional properties.
   4. Enable Reflector checkbox. This simulates a reflective surface behind the spot Light to adjust the visual intensity.

8. Make the light bulb Material emissive:

   1. In the Project window, select Assets/ExampleAssets/Materials/Lightbulb_Mat.mat.
   2. In the Inspector, go to Emission Inputs and enable Use Emission Intensity.
   3. Set Emissive Color to white, and set the Emission Intensity to 8500 Luminance.

9. If you disabled Auto Generate in step 2, go to the Lighting window and press the Generate Lighting button. You can also re-enable Auto Generate.