Unity Shader Coordinate Spaces (Cheat Sheet)

This mini note maps out the coordinate spaces in Unity shaders and the built-in matrices/macros that convert between them. Handy when you need to remember how positions travel from model space to the screen.

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Space overview

Vertices typically go through:

• Model/Object space – the mesh’s local coordinates
• World space – positions after applying the object transform
• View/Camera space – camera as origin and axes
• Clip space – after applying the projection matrix; ready for clipping

Think of it as multiplying by M, V, then P to reach clip space.

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Matrices & macros

• Model → World: unity_ObjectToWorld / UNITY_MATRIX_M
• World → View: unity_MatrixV / UNITY_MATRIX_V
• View → Clip: glstate_matrix_projection / UNITY_MATRIX_P

Combos:

• Model → View: UNITY_MATRIX_MV
• World → Clip: UNITY_MATRIX_VP
• Model → Clip (MVP): UNITY_MATRIX_MVP or helper UnityObjectToClipPos

Model → World

float4 worldPos = mul(unity_ObjectToWorld, v.vertex);

World → View

float4 viewPos = mul(unity_MatrixV, worldPos);

View → Clip

float4 clipPos = mul(UNITY_MATRIX_P, viewPos);

World → Clip

float4 clipPos = mul(UNITY_MATRIX_VP, worldPos);

Model → View

float4 viewPos = mul(UNITY_MATRIX_MV, v.vertex);

Model → Clip (MVP)

float4 clipPos = mul(UNITY_MATRIX_MVP, v.vertex);
// or
o.pos = UnityObjectToClipPos(v.vertex);

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Typical vertex shader

struct appdata {
    float4 vertex : POSITION;
};

struct v2f {
    float4 pos : SV_POSITION;
};

v2f vert (appdata v) {
    v2f o;
    o.pos = UnityObjectToClipPos(v.vertex);
    return o;
}

Need world space for lighting or projection? Compute worldPos and pass it through the interpolator.

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Summary

• Remember the chain: Model → World → View → Clip
• Know the Unity matrices (M, V, P, MV, VP, MVP)
• UnityObjectToClipPos hides the multiplications but understanding them makes custom effects easier

Original article (Chinese) on CSDN “uniGame”, CC BY-SA 4.0.
https://blog.csdn.net/alla_Candy/article/details/121176275