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llSetAlpha

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function
Function syntax
llSetAlpha(
  1. float alpha,// Transparency value to set, from 0.0 (clear) to 1.0 (solid; clamped to a minimum of 0.1).
  2. integer face// Face number or ALL_SIDES. Values: Faces
);
Energy
10

Sets the diffuse texture alpha (opacity) of face. If face is ALL_SIDES, applies to all faces. Values are clamped between 0.1 and 1.0 (where 1.0 is fully opaque).

Sets the Blinn-Phong alpha on face

How to use
llSetAlpha(0.0, 0);

Caveats

Section titled “Caveats”

  • llSetAlpha 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:

  • invisible

    if (llIsLinkGLTFMaterial(LINK_THIS, ALL_SIDES)) {
        llSetLinkGLTFOverrides(LINK_THIS, ALL_SIDES, [OVERRIDE_GLTF_BASE_ALPHA_MODE, PRIM_GLTF_ALPHA_MODE_BLEND, OVERRIDE_GLTF_BASE_ALPHA, 0.0]);
    } else {
        llSetAlpha(0.0, ALL_SIDES);
    }

  • visible

    if (llIsLinkGLTFMaterial(LINK_THIS, ALL_SIDES)) {
        llSetLinkGLTFOverrides(LINK_THIS, ALL_SIDES, [OVERRIDE_GLTF_BASE_ALPHA_MODE, "", OVERRIDE_GLTF_BASE_ALPHA, ""]);
    } else {
        llSetAlpha(1.0, ALL_SIDES);
    }

Examples

Section titled “Examples”
Example 1
8 collapsed lines
float cloakSpeed = 0.1;


default
{
    touch_end(integer total_number)
    {
        float alpha = 1.0;
        while(alpha > 0.0)
        {
            alpha -= 0.1;
            llSetAlpha(alpha, ALL_SIDES);
            llSleep(cloakSpeed);
        }
10 collapsed lines
        state cloaked;
    }
}


state cloaked
{
    touch_end(integer total_number)
    {
        float alpha;
        while (alpha < 1.0)
        {
            alpha += 0.1;
            llSetAlpha(alpha, ALL_SIDES);
            llSleep(cloakSpeed);
        }
        state default;
    }
}

Notes

Section titled “Notes”

In practical terms, “alpha” means “transparency” or “visibility”.

To be clear, llSetAlpha will only affect the prim that the script it is in. It will not affect any linked prims. To set the alpha state for those, use llSetLinkAlpha

See also

Section titled “See also”

Functions

Section titled “Functions”

Events

Section titled “Events”
Original wiki source

Some wiki templates and tables need their original context. View this article on the Second Life Wiki. Technical wording and examples are retained from the source; historical guidance may differ from current behavior.