llSetLinkAlpha

void llSetLinkAlpha(integer LinkNumber, float Opacity, integer Face)

If a prim exists in the link chain at LinkNumber, set Face to Opacity.

Sets the Face, on the linked prim specified, to the Opacity.

Parameters

LinkNumber (integer)
Opacity (float)
Face (integer)

Technical Details

Return Type: void
Energy: 10

llSetLinkAlpha will have no visible effect on faces with a PBR material. To work on faces both with and without a PBR material, use one of these snippets:

To make faces invisible:

llSetLinkAlpha(LINK_THIS, 0.0, ALL_SIDES);
llSetLinkPrimitiveParamsFast(LINK_THIS, [PRIM_GLTF_BASE_COLOR, ALL_SIDES, "", "", "", "", "", 0.0, PRIM_GLTF_ALPHA_MODE_MASK, 1.0, ""]);

To make faces visible:

llSetLinkAlpha(LINK_THIS, 1.0, ALL_SIDES);
llSetLinkPrimitiveParamsFast(LINK_THIS, [PRIM_GLTF_BASE_COLOR, ALL_SIDES, "", "", "", "", "", "", "", "", ""]);

Examples

Make the entire object disappear for 5 seconds

default
{
    touch_start(integer num_detected)
    {
        // transparent
        llSetLinkAlpha(LINK_SET, 0.0, ALL_SIDES);
        llSetTimerEvent(5.0);
    }

    timer()
    {
        // opaque
        llSetLinkAlpha(LINK_SET, 1.0, ALL_SIDES);
        llSetTimerEvent(0.0);
    }
}

Fade in and out on touch

default
{
    touch_start(integer num_detected)
    {
        // fade out
        float alpha = 1.0;
        while (alpha >= 0.0)
        {
            llSetLinkAlpha(LINK_SET, alpha, ALL_SIDES);
            alpha -= 0.001;
        }

        // fade in
        while (alpha < 1.0)
        {
            alpha += 0.001;
            llSetLinkAlpha(LINK_SET, alpha, ALL_SIDES);
        }
    }
}

Toggle prim visibility by name via chat commands

list PrimList = ["ALL"];
// Start our prim list with a dummy entry, so that the index into this list will correspond directly to the link number
// By making the dummy entry 'ALL' we provide a match for that option too

default
{
    changed (integer change)
    {
        if (change & CHANGED_LINK)
            llResetScript();
    }

    state_entry()
    {
        integer PrimCount = llGetNumberOfPrims();
        llListen(37, "", NULL_KEY, "");
        integer i;
        for (i = 1; i <= PrimCount; ++i)
            PrimList += llToUpper(llGetLinkName(i));
    }

    listen(integer channel, string name, key id, string msg)
    {
        list TempList = llCSV2List(llToUpper(msg));
        integer ListLen = llGetListLength(TempList);
        integer alpha = (llList2String(TempList, 0) == "SHOW");
        // 'SHOW' sets selected prims visible, otherwise set them transparent
        // e.g.  HIDE,PLATE,SPOON,NAPKIN            <---- makes named prims invisible
        // e.g.  SHOW,ALL                             <---- makes all prims visible

        integer i;
        for (i = 1; i < ListLen; ++i)
        {
            string ThisPrim = llStringTrim(llList2String(TempList, i), STRING_TRIM);
            integer LinkNumber = llListFindList(PrimList, [ThisPrim]);
            if (~LinkNumber)    // i.e. if LinkNumber != -1
            {
                if (!LinkNumber)
                    LinkNumber = LINK_SET;
                llSetLinkAlpha(LinkNumber, alpha, ALL_SIDES);
            }
        }
    }
}

llSetLinkAlpha

Examples

See Also