How we optimized our Game - Jake & Tess' Finding Monsters Adventure

How we optimized our Game – Jake & Tess’ Finding Monsters Adventure

Phil Lira Sr. Staff Engineer (Graphics) @phi_lira

RELEASE TRAILER

https://www.youtube.com/watch?v=STzdj04n7dc

TECHNICAL CHALLENGES

Technical challenges

Many custom shaders and effects

Technical challenges

Many custom shaders and effects

Technical challenges

Multiple characters with complex skinning

Our budget is the limit

• Push as much content as possible with smooth gameplay and no overheat– Can we get the same quality

with a similar approach?– Are we doing something we

don’t need to?

What if we hit our budge

• What happens when we fail?– Either gameplay or visual quality

will be impacted

• When it comes to remove effects, trust is important

OPTIMIZATION PROCESS

Optimization Process

• Do not make any assumptions. • A profiler will tell you where the bottleneck is.

Profile Optimize Test

Optimization Process

• Rewrite code to use resources more efficiently• Often we can fake or simplify effects • Experience comes into play here.

OptimizeProfile Test

Optimization Process

• Guarantee your tests have same conditions• Did you work reduced overall gpu ms?

TestProfile Optimize

How to find our bottleneck?

• Unity comes with a built-in profiler that does most of the work

• We wanted to have more detailed GPU info

– Adreno Profiler – Snapdragon GPUs– Mali Graphics Debugger (MGD) and

DS-5 Streamline – Mali GPUs

Adreno GPU Profiler

How to find our bottleneck?

Disable GL

Frame rate increased?

No Yes

CPU Bound GPU Bound

Vertex Frag Memory

How to find our bottleneck?

• Vertex– #triangles– Vertex shader– Per-vertex lighting

• Fragment– Fragment Shader (instruc. / sample)– Blend Ops– Per-Pixel light (forward rendering)

• Bandwidth– Large textures– Dependent Texture Reads– Block Resolve (ReadPixels)

CASE STUDY – ROYAL MOON

Case Study – Royale Moon

• Triangles 106k• Drawcalls 87• Overdraw 2.51x• Shader Stats:

– Up to 160 ALU/Frag– Up to 7 texture samples

• Adreno %Time Shading Fragment - max– Fragment bound

Overdraw Debug

Case Study – Royale Moon

• Early Z-Test Discards occluded fragments

• Render Order Matters

• Optimized Render Order– Opaques – Front to Back– Skybox– Transparent – Back to Front– Overlay (UI / HUD)

We need to improve this

How to assign object to sorting layers?• Per Shader

– Have to duplicate shader files. Hard to maintain because we have to make changes individually to each duplicate.

• Per Mesh– Not scalable, requires lot of work. – Risky! May break batches by mistake.

• Per Material– YES!– In that case do not use same material for different scene

• While you fix sort for one might break for the other.

Custom Material Inspector

• Created an editor script BRSMaterialEditor to set Material.renderQueue

• Add CustomEditor “BRSMaterialEditor”

to the end of shader file.

Character and Props

Camera Island Top

Outer Islands

Skydome

Before and After Improving Sort

Reduced from 2.51 to 1.91

Z-Reject

FRAGMENT SHADER

Shader hotzone (% time shading)

Shader hotzone (ALU per frag)

• Improving Shader Instructions– Model: ops that can be done once per drawcall

• Use scripts to compute and pass values to shader• Input Vector Normalization (ex. Rim Light)• Scroll Offset

– Vertex: Ops that can be done per vertex• Uniform texture tile & offset

– Fragment: Ops that needs to be done per pixel• Equation simplification• Half & Fixed precision for better thermal• Saturate vs max(0.0, dot)

Fragment

Vertex

Model

COM

PLEX

ITY

How to optimize fragment shader

Optimizing Shaders

• Many custom shaders done in ShaderForge– ShaderForge does heavy work on fragment

• Many variants and not exactly the same code structure

• How to optimize them all?– 1st pass optimizing in ShaderForge– 2nd pass optimizing in Code

1st Pass: ShaderForge

• Identify core changes to lighting model– BlinnPhongWrapped– BlinnPhongRamp

• Created custom code node– Artist helped with the process to replace for this code– This made shader code common and more organized

1st Pass: ShaderForge

Custom Lightmap in ShaderForge

• One major art complain was the lack of support for lightmap in custom lighting

• Created a Lightmap node for them• Problem1: Need to enable lightmap in config shader header.• Problem2: ShaderForge does not exposes interpolated data.

2nd Pass: Shader Code

Created a cginc file with macros for optimized code• ShaderForge follows name convention for

input data

The results - Ground Shader

After optimization:

Before optimization:

• Avg ALU/Frag – ~21% reduction• Fragments Shaded – ~45% reduction Overall Improvement: ~7ms• Fragment Instructions – ~64% reduction

Further Improvements

• Fallback Shader– We came across some problems

with shaders not being supported for some configurations

– Vertex Animation with a noise texture (tex2dlod) is not supported on OpenGL ES 2.0 profiles

– Fallback shader to standout in those cases

– Makes it easy to differentiate from other errors

ASTC

TEXTURE TEXTURE COMPRESSIONCOMPRESSION

ASTC

• Optimal performance with high quality

• Improves bandwitdh and power consuption

• Galaxy Note 4, Galaxy S6 and above support it

• Supported with OpenGL 3 Unity profile

ASTC

ASTC 4x4 ASTC 6x6 ETC 2

ASTC

Format RGB RGBA Normal MapCodec ASTC 6x6 ASTC 4x4 ASTC 4x4BPP 3.56 8 8

Size vs Uncompressed

14.8% 50% 50%

Size vs ETC2 89% 100% 100%

Recommended Settings:

Review

• Do not make assumptions, use a profiler.• GPU profilers will give you in-depth data per drawcall• One can assign objects to sorting layers at material

level for best workflow• Reduce amount of work to optimize shader by

creating means to reuse optimized code. • ASTC texture compression is best option available

for quality but only supported in a few devices.

Phil Liraf.lira@samsung.com @phi_lira

Q&A

CONTACTS

www.blackriverstudios.net@BlackRvrStudios/blackrivergames

Phil Liraf.lira@samsung.com @phi_lira

THANKS!

CONTACTS

www.blackriverstudios.net@BlackRvrStudios/blackrivergames