PRIM ALPHA MODE

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Description

Constant: integer PRIM_ALPHA_MODE = 38;

The integer constant PRIM_ALPHA_MODE has the value 38

Used to specify how the alpha channel of the diffuse texture should affect rendering of a prim’s face.

llSetPrimitiveParams

[ PRIM_ALPHA_MODE, integer face, integer alpha_mode, integer mask_cutoff ]
• integer face a face number or ALL_SIDES
• integer alpha_mode PRIM_ALPHA_MODE_* flag
• integer mask_cutoff when the alpha rendering mode is PRIM_ALPHA_MODE_MASK, sets the alpha value above which a pixel renders as fully opaque, in the range 0 to 255

When used with llSetPrimitiveParams & llSetLinkPrimitiveParams

llGetPrimitiveParams

llGetPrimitiveParams([ PRIM_ALPHA_MODE, integer face ]);

Returns the listinteger alpha_mode, integer mask_cutoff ]

• integer face a face number or ALL_SIDES

• integer alpha_mode PRIM_ALPHA_MODE_* flag
• integer mask_cutoff when the alpha rendering mode is PRIM_ALPHA_MODE_MASK, sets the alpha value above which a pixel renders as fully opaque, in the range 0 to 255
alpha_mode Flags V Description Notes
PRIM_ALPHA_MODE_NONE 0 Render the diffuse texture as though the alpha channel were nonexistent The viewer’s build tool sets this by default when a face has a material and no alpha channel is present in the diffuse texture.
PRIM_ALPHA_MODE_BLEND 1 Render the diffuse texture with alpha-blending. This value is also used as the default to clear the materials settings from a prim face.
PRIM_ALPHA_MODE_MASK 2 Render the prim face in alpha-masked mode. Diffuse texture pixels which are more opaque than mask_cutoff will be rendered as fully opaque, while the other pixels will be fully transparent.
PRIM_ALPHA_MODE_EMISSIVE 3 Render the prim face in emissivity mode. Diffuse texture pixels opacity maps to their emissivity when rendered. Fully opaque pixels will effectively be rendered as ‘full bright’.

Caveats

Important Issues

~ All Issues ~ Search JIRA for related Bugs
   We need PRIM_ALPHA_MODE_DEFAULT to revert alpha to old "if the texture has an alpha mask, use alpha. If not, don't" behavior.

Examples

llSetPrimitiveParams([ PRIM_ALPHA_MODE, ALL_SIDES, PRIM_ALPHA_MODE_NONE, 0 ]);
llSetPrimitiveParams([ PRIM_ALPHA_MODE, ALL_SIDES, PRIM_ALPHA_MODE_MASK, 130 ]);

Notes

Deep Notes

All Issues

~ Search JIRA for related Issues
   We need PRIM_ALPHA_MODE_DEFAULT to revert alpha to old "if the texture has an alpha mask, use alpha. If not, don't" behavior.

Signature

integer PRIM_ALPHA_MODE = 38;