# Projects a PVector onto camera

**URL:** <https://discourse.processing.org/t/projects-a-pvector-onto-camera/7908>\
**Category:** Coding Questions\
**Created:** [January 28, 2019, 8:09pm UTC](https://discourse.processing.org/t/projects-a-pvector-onto-camera/7908 "2019-01-28T20:09:29Z")\
**Posts on this page:** 1\
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**Author:** ![jeremydouglass](https://yyz2.discourse-cdn.com/flex036/user_avatar/discourse.processing.org/jeremydouglass/32/20_2.png) [@jeremydouglass](https://discourse.processing.org/u/jeremydouglass)\
**Post date:** [February 11, 2019, 9:31pm UTC](https://discourse.processing.org/t/projects-a-pvector-onto-camera/7908/4 "2019-02-11T21:31:07Z")

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I’m not seeing Camera.project in the three.js documentation, so I’m not totally clear on what the function does – [three.js docs](https://threejs.org/docs/#api/en/cameras/Camera) – can you link to the documentation?

**Edit – found it: Vector3.project()**: [three.js docs](https://threejs.org/docs/#api/en/math/Vector3.project)

**and**

> <https://github.com/mrdoob/three.js/blob/master/src/math/Vector3.js#L315-L319>

I think perhaps you should look at the reference

> **[Reference](https://processing.org/reference/)**
>
> Find further documentation of the Processing language

and specifically the Camera section functions and the Matrix functions, such as:

> **[camera() / Reference](https://processing.org/reference/camera_.html)**
>
> Sets the position of the camera through setting the eye position, the center of the scene, and which axis is facing upward. Moving the eye position and the direction it is pointing (the center of the …

> **[perspective() / Reference](https://processing.org/reference/perspective_.html)**
>
> Sets a perspective projection applying foreshortening, making distant objects appear smaller than closer ones. The parameters define a viewing volume with the shape of truncated pyramid. Objects near …

> **[applyMatrix() / Reference](https://processing.org/reference/applyMatrix_.html)**
>
> Multiplies the current matrix by the one specified through the parameters. This is very slow because it will try to calculate the inverse of the transform, so avoid it whenever possible. The equivalen…

Is your question related to this?

> [@Planar equation from camera image](https://discourse.processing.org/t/planar-equation-from-camera-image/8164):
>
> Hi, I’m new to the forum. I’ve appended a jpeg to illustrate my question, sorry for its amateurish appearance. My question: in the given setup, how do I calculate the equation of the image plane from 3 points – pp1, pp2, pp3? I understand how to solve for the 3D plane in real world points that are behind the projected points but not from its projected points.

See also PMatrix3D.invert:

> **[Matrix.Invert ? .. - Processing Forum](https://forum.processing.org/one/topic/matrix-invert.html)**
>
> Processing Forum

[http://processing.github.io/processing-javadocs/core/processing/core/PMatrix3D.html#invert--](http://processing.github.io/processing-javadocs/core/processing/core/PMatrix3D.html#invert--)

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