---
title: "ray(to:forViewPort:)"
framework: modelio
role: symbol
role_heading: Instance Method
path: "modelio/mdlcamera/ray(to:forviewport:)"
---

# ray(to:forViewPort:)

Returns a point, in 3D world coordinates, corresponding to the specified 2D view coordinates.

## Declaration

```swift
func ray(to pixel: vector_int2, forViewPort size: vector_int2) -> vector_float3
```

## Parameters

- `pixel`: A point in the 2D pixel coordinate system of a possible renderer’s view.
- `size`: The pixel dimensions of a possible renderer’s view.

## Return Value

Return Value A set of 3D world coordinates.

## Discussion

Discussion This method projects a ray from the camera’s location in the direction of the specified view coordinates, returning the world coordinates where that ray intersects a plane at a distance of 1.0 units (of world coordinate space) away from the camera.

## See Also

### Managing Camera Perspective

- [projectionMatrix](modelio/mdlcamera/projectionmatrix.md)
- [projection](modelio/mdlcamera/projection.md)
- [MDLCameraProjection](modelio/mdlcameraprojection.md)
- [nearVisibilityDistance](modelio/mdlcamera/nearvisibilitydistance.md)
- [farVisibilityDistance](modelio/mdlcamera/farvisibilitydistance.md)
- [fieldOfView](modelio/mdlcamera/fieldofview.md)
- [worldToMetersConversionScale](modelio/mdlcamera/worldtometersconversionscale.md)