Babylon.js/materialsLibrary/src/background/backgroundVertexDeclaration.fx

uniform mat4 view;
uniform mat4 viewProjection;
uniform float shadowLevel;

#ifdef DIFFUSE
uniform mat4 diffuseMatrix;
uniform vec2 vDiffuseInfos;
#endif

#ifdef REFLECTION
    uniform vec2 vReflectionInfos;
    uniform mat4 reflectionMatrix;
    uniform vec3 vReflectionMicrosurfaceInfos;
#endif

#ifdef POINTSIZE
uniform float pointSize;
#endif