URP vs SRP in Unity: Key Differences

Unity’s rendering architecture has evolved significantly to provide developers with more control, flexibility, and performance optimizations. A major step in this evolution is the Scriptable Render Pipeline (SRP)—a system that allows developers to customize and control the rendering process. URP (Universal Render Pipeline) is Unity’s ready-to-use pipeline built on top of SRP.

What is Scriptable Render Pipeline (SRP)?

The Scriptable Render Pipeline is a foundational rendering architecture introduced in Unity to replace the built-in pipeline with something more customizable and modular. It allows developers to write their own rendering logic in C#, tailoring how scenes and assets are rendered.

🧠 Key Features of SRP

• Full control over rendering: You define how cameras, lights, shadows, post-processing, and materials are rendered.
• Written in C#: The rendering logic is scripted, enabling version control, debugging, and better team collaboration.
• Modular and customizable: You can write a lightweight renderer for mobile or a high-end one for desktop and console.

🎯 Use Case

Ideal for AAA studios and advanced teams who need fine-grained control over every step of the rendering process, such as custom shading models, lighting pipelines, or performance-optimized rendering for specific hardware.

What is Universal Render Pipeline (URP)?

The Universal Render Pipeline (formerly LWRP) is a ready-to-use implementation of SRP, designed by Unity to be scalable and performant across a wide range of platforms, from mobile to VR to consoles.

🧰 Key Features of URP

• Out-of-the-box rendering solution: Built on top of SRP but pre-configured with optimized rendering features.
• Cross-platform: Runs efficiently on mobile, PC, WebGL, VR, and consoles.
• Improved performance: Uses forward rendering, scriptable culling, and renderer features to reduce draw calls and overdraw.
• Renderer Features: Extend URP functionality with custom passes, post-processing effects, or lighting tweaks without creating a whole new pipeline.

🎯 Use Case

URP is ideal for indie devs, studios, and teams looking for great visuals + optimized performance without needing to write a custom renderer.

 Key Differences Between URP and SRP

Feature	URP (Universal Render Pipeline)	SRP (Scriptable Render Pipeline)
Definition	A prebuilt render pipeline using SRP	A framework to build custom render pipelines
Purpose	Provides a general-purpose solution	Offers deep control over rendering logic
Customization	Limited to shader graphs, renderer features, and basic extensions	Full control via C# scripting; can rewrite entire pipeline
Complexity	Beginner to Intermediate	Advanced (requires graphics programming knowledge)
Performance	Optimized and balanced for most platforms	Depends on implementation; can be ultra-optimized or heavy
Rendering Path	Mostly forward rendering (with deferred support from Unity 2022.2+)	Customizable: forward, deferred, clustered, hybrid, etc.
Usage Scenario	Games, mobile apps, VR apps with standard needs	Cinematics, proprietary engines, experimental graphics
Example Projects	Mobile games, VR apps, multiplatform games	Custom engines, high-end desktop/console games

Real-world Analogy

Think of SRP as a professional-grade kitchen with every tool and ingredient where you build your recipe from scratch. Meanwhile, URP is like a meal kit—ingredients are pre-measured and the recipe is tested, but you can still tweak it to suit your taste.

Technical Comparison: Under the Hood

Component	URP	SRP
Shader Model	Uses HLSL with Shader Graph or handwritten shaders compatible with URP	Completely open to custom shaders and pipelines
Post-Processing	Integrated with URP package	Requires custom implementation or integration
Lighting	Real-time and baked lighting with options for 2D lights	Fully configurable lighting pipelines
Custom Renderer	Through Renderer Features	Build everything from scratch (camera stack, culling, etc.)

When to Use URP vs SRP

✅ Choose URP if

• You want fast development and optimized visuals out-of-the-box.
• You're building mobile, web, or cross-platform games.
• You don’t want to spend time writing a renderer from scratch.

✅ Choose SRP if

• You need custom rendering logic (e.g., non-standard shading, hybrid rendering).
• You are developing an in-house engine or tool.
• You want ultimate performance tuning on specific hardware.

Transition from Built-in Pipeline to URP/SRP

Moving to URP or SRP from Unity’s Built-in Render Pipeline requires:

• Material and shader conversion (built-in shaders won't work in URP).
• Lighting adjustments (URP handles lighting and post-processing differently).
• Camera and post-processing setup updates.
• Script adjustments if you were using built-in rendering functions.

Unity Roadmap & Future

Unity is moving towards fully supporting SRP-based pipelines and plans to deprecate the Built-in Render Pipeline in the future. URP and HDRP (High Definition Render Pipeline) are Unity's main supported pipelines under SRP.

If you’re starting a new project in 2025, using URP or a custom SRP is highly recommended.

Final Thoughts

The key difference between URP and SRP in Unity lies in customizability vs convenience. URP is a flexible, general-purpose pipeline ideal for most use cases. SRP, on the other hand, is a blank canvas for developers who want full control over how scenes are rendered.