Kommentar
Åtkomst till den här sidan kräver auktorisering. Du kan prova att logga in eller ändra kataloger.
Åtkomst till den här sidan kräver auktorisering. Du kan prova att ändra kataloger.
Partial precision logp₂(x).
Syntax
| logp dst, src |
|---|
where
- dst is the destination register.
- src is a source register. Source register requires explicit use of replicate swizzle, that is, exactly one of the .x, .y, .z, .w swizzle components (or the .r, .g, .b, .a equivalents) must be specified.
Remarks
| Vertex shader versions | 1_1 | 2_0 | 2_x | 2_sw | 3_0 | 3_sw |
|---|---|---|---|---|---|---|
| logp | x | x | x | x | x | x |
The following code fragment shows the operations performed.
float f = abs(src);
if (f != 0)
dest.x = dest.y = dest.z = dest.w = (float)(log(f)/log(2));
else
dest.x = dest.y = dest.z = dest.w = -FLT_MAX;
This instruction provides logarithm base 2 partial precision, up to 10 bits.
Related topics