---
title: simd_incircle
framework: simd
role: symbol
role_heading: Function
path: simd/simd_incircle-8iogb
---

# simd_incircle

Tests if a double-precision point lies inside, on, or outside a circle.

## Declaration

```occ
static double simd_incircle(simd_double2 __x, simd_double2 __a, simd_double2 __b, simd_double2 __c);
```

## Parameters

- `__x`: The point that the function tests.
- `__a`: The first point that determines the circle.
- `__b`: The second point that determines the circle.
- `__c`: The third point that determines the circle.

## Return Value

Return Value A value that indicates whether the point lies inside, on, or outside the specified circle.

## Discussion

Discussion If the points a, b, and c describe a positively- or counterclockwise-oriented circle, the function returns: A positive value if x is inside the circle Zero if x is on the circle A negative value if x is outside the circle The function flips sign of the return value if the circle is negatively- or clockwise-oriented.

## See Also

### Geometry Functions

- [simd_cross](simd/simd_cross-1dixl.md)
- [simd_dot](simd/simd_dot-3r1vl.md)
- [simd_normalize](simd/simd_normalize-9fo1c.md)
- [simd_fast_normalize](simd/simd_fast_normalize-9wy6m.md)
- [simd_precise_normalize](simd/simd_precise_normalize-54dru.md)
- [simd_orient](simd/simd_orient-9fgki.md)
- [simd_orient](simd/simd_orient-9b2wf.md)
- [simd_project](simd/simd_project-1mg5p.md)
- [simd_fast_project](simd/simd_fast_project-6c68k.md)
- [simd_precise_project](simd/simd_precise_project-7t3qn.md)
- [simd_reflect](simd/simd_reflect-7c8f9.md)
- [simd_refract](simd/simd_refract-4ani9.md)