Raycaster.setFromCamera is incorrect for back half of OrthographicCamera frustum.

It appears to be failing here

Correct calculation, to start the ray from back of the frustum I think should be:

this.ray.origin.set( coords.x, coords.y, camera.near / ( camera.near - camera.far ) ).unproject( camera ); 

Notice the sphere position is not updated in back half of the frustum in live example:

• jsfiddle (dev branch)

Three.js version

• Dev

Browser

• All of them

OS

• All of them

[WestLangley]

The three.js examples should not be using a negative near plane. Rendering objects that are behind the camera can be confusing to users and can cause objects to be back-lit. Raycasting from the near clipping plane when the near clipping plane is behind the camera will result in the returned distance to the the intersected object being incorrect.

[arodic]

@Mugen87 right now I used negative plane for convenience. For example if I wanted to rotate OrthographicCamera around a point and see entire scene, I could simply put the camera there, set near/far to encompass the scene and rotate (no target/lookAt required).

However, I think this boils down do how we think about cameras. Perspective camera is kind of like a real world camera. Its projection geometry is a frustum and it shoots things in front of its center.

Orthographic camera, on the other hand, has a cuboid projection geometry and restricting it to front of the camera center seems arbitrary. Moreover, threejs examples use negative near plane and rendering a scene with negative near plane results with a perfectly fine and expected result…