SVG - dégradé

[Wells]

Juste pour un test :

<circle cx="{$placer_x}" cy="{$placer_y}" r="10" style="filter:url(#dropshadow);"/>

Code :

<filter id="dropshadow">
                    <feFlood        flood-color="#ff0000"            result="glowcolor"/>
                    <feFlood        flood-color="transparent"    result="fillcolor"/>
                    <feFlood        flood-color="#0000ff"               result="strokecolor"/>
        
                    <feGaussianBlur    stdDeviation="40"    in="SourceGraphic"    result="glow0"/>
                    <feComposite    in="glow0"            in2="SourceAlpha"    operator="in"    result="glow1"    />
                    <feColorMatrix    in="glow1"             values="0 0 0 0 1 0 0 0 0 1 0 0 0 0 1 1 1 1 0 0"    result="glow2"/>
                    <feComposite    in="glowcolor"        in2="glow2"        operator="in"    result="glow"/>
        
                    <feComposite    in="fillcolor"        in2="SourceGraphic"    operator="in"    result="fill"/>
                    <feColorMatrix    in="SourceGraphic"    type="luminanceToAlpha"             result="strokealpha"/>
                    <feComposite    in="strokecolor"        in2="strokealpha"    operator="in"    result="stroke"/>
                    <feMerge>
                        <feMergeNode     in="fill"/>
                        <feMergeNode    in="glow"/>
                        <feMergeNode     in="stroke"/>
                    </feMerge>
                </filter>

Rien ne s'affiche. je pense que ca ne fonctionne pas sur un element circle :'(