Hello LSL masters, So I'm trying to create a mesh animated object. The most common way to make this is to use llSetLinkAlpha and to switch from 0/100 visibility etc. The problem is that llSetLinkAlpha is using 'alpha blending' even if it's set to 100% invisible. This makes viewer to still try to sort the alphas and kills the framerate. So my plan was to use PRIM_ALPHA_MODE_MASK which must switch to 'alpha testing' mode and it should ease the rendering. my code: llSetLinkPrimitiveParamsFast(LINK_THIS,[ PRIM_TEXTURE, face-1, TEXTURE_TRANSPARENT, <1.0, 1.0, 0.0>, ZERO_VECTOR, 0.0, PRIM_ALPHA_MODE, face-1, PRIM_ALPHA_MODE_MASK, 255, PRIM_TEXTURE, face , "some non alpha texture uuid", <1.0, 1.0, 0.0>, ZERO_VECTOR, 0.0, PRIM_ALPHA_MODE, face, PRIM_ALPHA_MODE_NONE, 0]); As you can see I'm animating texture faces instead of objects. If I use llSetLinkAlpha everything works and It's very reliable. But if use the code above a random face decide not to change parameters or PRIM_ALPHA_MODE is not changed at all. It's very weird and I'm just not sure if it's a bug or I'm doing something wrong? Is there a clever workaround this ? Thank you very much for spending time reading this. Regards