Techniques for accurate and faithful projections in an outdoor augmented reality view

1. A method for projecting information onto a surface in an augmented reality view of a physical environment, comprising:

pre-capturing topography of the surface by

capturing images of the physical environment that include the surface with a camera,

generating a three dimensional (3D) reality mesh using the camera-captured images, the 3D reality mesh being a 3D polygon mesh representation of the surface generated using the camera-captured images that indicates topography of the surface;

pre-projecting information onto the pre-captured topography by

aligning the 3D reality mesh with a 3D model or 2D drawing,

projecting information based on the 3D model or 2D drawing onto the topography indicated in the 3D reality mesh; and

subsequent to the pre-capturing and pre-projecting, generating an augmented reality view on an augmented reality device by

capturing a live view of the physical environment,

aligning the 3D reality mesh and pre-projected information with the live view, and

combining the live view with the pre-projected information to produce the augmented reality view that is displayed on the augmented reality device.

2. The method of claim 1 , wherein the generating uses structure-from-motion (SfM) photogrammetry.

3. The method of claim 1 , wherein surface is a road surface and the pre-projected information represents subsurface features.

4. The method of claim 3 , wherein the subsurface features comprise subsurface utilities.

5. The method of claim 1 , wherein the pre-projecting further includes:

scaling the 3D reality mesh to a same scale as the 3D model or 2D drawing.

6. The method of claim 1 , wherein the pre-projecting further comprises:

maintaining the pre-projected information and the 3D reality mesh with a same georeference.

7. The method of claim 1 , wherein the generating the 3D reality mesh, the aligning the 3D reality mesh with the 3D model or 2D drawing and the projecting information are performed on one or more electronic devices separate from the augmented reality device, and the method further comprises pre-loading the 3D reality mesh and the pre-projected information on the augmented reality device.

8. The method of claim 1 , wherein aligning the 3D reality mesh with the live view further comprises:

manually or automatically establishing points of correspondence between features in the 3D reality mesh and corresponding features in the live view of the physical environment.

9. The method of claim 1 , wherein the 3D reality mesh is not displayed in the augmented reality view.

10. A method for projecting information onto a surface in an augmented reality view of a physical environment, comprising:

pre-capturing topography of the surface by generating a three dimensional (3D) reality mesh that indicates topography of the surface, the 3D reality mesh being a 3D polygon mesh representation of the surface generated using camera-captured images;

pre-projecting information onto the pre-captured topography;

subsequent to the pre-capturing and pre-projecting, generating an augmented reality view on an augmented reality device by

capturing a live view of the physical environment,

aligning the 3D reality mesh and pre-projected information with the live view, and

combining the live view with the pre-projected information to produce the augmented reality view that is displayed on the augmented reality device.

11. The method of claim 10 , wherein the pre-capturing further comprises:

generating the 3D reality mesh using the camera-captured images using structure-from-motion (SfM) photogrammetry.

12. The method of claim 10 , wherein the pre-projecting further comprises:

aligning the 3D reality mesh with a 3D model or 2D drawing; and

projecting information based on the 3D model or 2D drawing onto the topography indicated in the 3D reality mesh.

13. The method of claim 10 , wherein the surface is a road surface and the pre-projected information represents subsurface features.

14. The method of claim 13 , wherein the subsurface features comprise subsurface utilities.

15. The method of claim 10 , wherein the pre-capturing topography and pre-projecting information are performed on one or more electronic devices separate from the augmented reality device, and the method further comprises pre-loading the 3D reality mesh and the pre-projected information on the augmented reality device.

16. The method of claim 10 , wherein aligning the 3D reality mesh with the live view further comprises:

manually or automatically establishing points of correspondence between features in the 3D reality mesh and corresponding features in the live view of the physical environment.

17. The method of claim 10 , wherein the 3D reality mesh is not displayed in the augmented reality view.

18. A non-transitory electronic device readable medium having instructions stored thereon, the instructions when executed by one or more electronic devices operable to:

generate a three-dimensional (3D) reality mesh by applying structure-from-motion (SfM) photogrammetry to camera-captured images of the physical environment that include a surface, the 3D reality mesh being a 3D polygon mesh representation of the surface generated using the camera-captured images that indicates topography of the surface;

align the 3D reality mesh with a 3D model or 2D drawing;

project information based on the 3D model or 2D drawing onto the topography indicated in the 3D reality mesh;

align the 3D reality mesh and pre-projected information with a live view of the physical environment; and

combine the live view with the pre-projected information to produce an augmented reality view that is displayed.

19. The non-transitory electronic device readable medium of claim 18 , wherein the surface is a road surface and the pre-projected information represents subsurface features.

20. The non-transitory electronic device readable medium of claim 18 , wherein the instructions when executed by the one or more electronic devices are further operable to:

maintain the projected information and the 3D reality mesh with a same georeference.