z

The z attribute defines the location along the z-axis for a light source in the coordinate system established by the primitiveUnits attribute on the <filter> element, assuming that, in the initial coordinate system, the positive z-axis comes out towards the person viewing the content and assuming that one unit along the z-axis equals one unit in x and y.

Two elements are using this attribute: <fePointLight> and <feSpotLight>

html, body, svg {
  height: 100%;
}

<svg viewBox="0 0 420 200" xmlns="http://www.w3.org/2000/svg">
  <filter id="diffuseLighting1" x="0" y="0" width="100%" height="100%">
    <feDiffuseLighting in="SourceGraphic">
      <fePointLight x="60" y="60" z="10" />
    </feDiffuseLighting>
  </filter>
  <filter id="diffuseLighting2" x="0" y="0" width="100%" height="100%">
    <feDiffuseLighting in="SourceGraphic">
      <fePointLight x="60" y="60" z="50" />
    </feDiffuseLighting>
  </filter>

  <rect x="0" y="0" width="200" height="200" style="filter: url(#diffuseLighting1);" />
  <rect x="0" y="0" width="200" height="200" style="filter: url(#diffuseLighting2); transform: translateX(220px);" />
</svg>

fePointLight

For <fePointLight>, z defines the location along the z-axis for the light source in the coordinate system established by the primitiveUnits attribute on the <filter> element.

feSpotLight

For <feSpotLight>, z defines the location along the z-axis for the light source in the coordinate system established by the primitiveUnits attribute on the <filter> element.

Specifications