colinleung-nilocat/unityurp-mobilescreenspaceplanarreflection

Reusable RendererFeature of MobileScreenSpacePlanarReflection

UnityURP-MobileScreenSpacePlanarReflection

A simple and fast ScreenSpacePlanarReflection(SSPR) as a standalone reusable RendererFeature in URP.
Can run on PC/console/vulkan android, other platforms not tested but should work if compute shader is supported.

• See runtime video here: https://youtu.be/Cy46A8EyX4Q
• download pre-built .apk here: https://drive.google.com/file/d/14Z_Gjb1ADz8RhcBgAFpa96dm-oQuOyQx/view?usp=sharing

SSPR ON SSPR OFF SSPR ON SSPR OFF

On Adreno630 GPU android mobile device(almost all 2018/2019 flagship android mobiles), Toggle SSPR ON/OFF:

• cost <1ms to update 128 height SSPR RT
• cost <1ms to update 256 height SSPR RT
• cost 1~2ms to update 512 height SSPR RT

On Adreno612 GPU android mobile device(Samsung Galaxy A70), Toggle SSPR ON/OFF:

• cost <1ms to update 128 height SSPR RT
• cost 1~2ms to update 256 height SSPR RT
• cost 4~5ms to update 512 height SSPR RT

On Adreno506 GPU android mobile device(Lenovo S5), Toggle SSPR ON/OFF:

• cost ~1ms to update 128 height SSPR RT
• cost 3~4ms to update 256 height SSPR RT
• cost 8~9ms to update 512 height SSPR RT

Where are the important files?

There are only 4 important code files, all inside a folder "Assets \ _MobileSSPR \ ReusableCore".
https://github.com/ColinLeung-NiloCat/UnityURP-MobileScreenSpacePlanarReflection/tree/master/Assets/_MobileSSPR/ReusableCore
Other files are for demo only, not important.

Can it run on mobile?

Tested on ~10 android devices(all support Vulkan). If your android device support Vulkan, result should be correct and rendering should be fast enough. (OpenGLES3.2 is not enough, must support Vulkan!)

*We have received a report that this SSPR is not working on MaliT760 GPU android (Galaxy S6), but we don't have this device to reproduce it

How to try this inside my own URP project?

• copy "Assets \ _MobileSSPR \ ReusableCore" folder to your project (contains 4 important code files)

• turn on "Depth Texture" in all your project's URP's setting

• turn on "Opaque Texture" in all your project's URP's setting

• Add MobileSSPRRendererFeature(RendererFeature) to your forward renderer asset

• create a new plane game object in your scene (set world space pos y = 0.01)

• create a material using MobileSSPRExampleShader.shader

• assign this material to your new plane

• DONE! You should see correct reflection both in scene and game window

I can see some small flickering in reflection / can't see any reflection

It is not expected! Please report your device name in Issues, thanks!

Notes

It is not safe to use InterlockedMin() and RenderTexture color format "RInt" on android/iOS compute shader(see -> https://zhuanlan.zhihu.com/p/150890059). Instead, we will use RenderTexture color format RFloat / ARGBHalf to produce similar result.

Editor

2020.3.33f1 LTS

Implementation reference

• http://remi-genin.fr/blog/screen-space-plane-indexed-reflection-in-ghost-recon-wildlands/
• http://advances.realtimerendering.com/s2017/PixelProjectedReflectionsAC_v_1.92_withNotes.pdf
• https://zhuanlan.zhihu.com/p/150890059
• https://github.com/Steven-Cannavan/URP_ScreenSpacePlanarReflections
• UE4 source - PostProcessPixelProjectedReflectionMobile.usf (UE4 4.26)

Change log

• 2020-08-23: add iOS/OSX support (with the help of MusouCrow)
• 2022-05-02: upgrade project to Unity2020.3.33f1, merged a bug fix in MobileSSPRComputeShader.compute

unityurp-mobilescreenspaceplanarreflection's Issues

No reflection on macOS (Metal)

@ColinLeung-NiloCat Thank you very much for fixing the reflection when changing the height of the plane. Reflections now work perfectly on Windows and Android with Vulkan.

Unfortunately reflections are missing on the M1 MacBook Air using Metal. Enabling them gives this error:

CommandBuffer: temporary render texture _MobileSSPR_PackedDataRT not found while executing SSPR (SetComputeTextureParam)
UnityEngine.GUIUtility:ProcessEvent (int,intptr,bool&)

I get the same error in my own project as well as a clone of this repo. The error occurs in the latest Unity 2021 LTS (2021.3.15f1) as well as the latest Unity 2020 LTS (2020.3.42f1).

How to use SSPR in AR scene?

Now Unity URP project of AR Foundation works well and Unity URP SSPR project works well too. But when I add the two Renderer Features in Pipeline_Renderer, there is no reflection of the ground. Do you know why? Are the two Renderer Features conflict? How to reslove this?

on Untiy2020.2 reflection is up side down and with many flickering in reflection

on Untiy2020.2 reflection is up side down and with many flickering in reflection

No reflections in 2022.1.17f1

Hi! Cant get reflections in 2022.1.17f1.
Some errors here.
Can you help please?

Does not work for webgl

Great work, but after downloading same project and just building for webgl whole screen turns black when mobile screen space reflections are turned on.

Black texture and low quality

I have a 50*4 scale plane. I added this script to it, but the quality is very poor and the base texture become black.

Does not work correctly in Unity 2020.1

After upgrading to Unity 2020.1.3f1 the results are not the same as Unity 2019.4

Transparency will render under reflective surface

Hi! I tried to use the reflection shader on a flat surface, and it worked well, but as soon as I popped some particles on top of it they were rendered behind the reflective surface. Is there any way to fix that? Thanks!

Unity 219.4.16f1 (LTS)

Horizontral Rection Plane Height WS is not Correct

When I change the SSRPGround's world pos Y to 1, and change the Horizontral Rection Plane Height WS in settings to 1.
The Reflection is not work correctly.

Depth bug when using OpenGLES graphics API

If change the graphics API whatever in editor or android runtime, the effect will be like this.

which height looks like not correct ,but the real reason is the depth is not corrct.
Because the depth range in opengl i [-1,1], dx and vulkan is [0,1].
so add this code is enough.

Have transparency support in the shader

Hi, Is it possible to have base texture as transparent one, so it will blend with background color, like floor/plane edges will be blended with background color due to the smooth transparency in the edge of texture/base map.