Method and apparatus for rendering a 3-dimensional scene
Provided herein are methods and systems to provide for parallax correction for multiple eye-points in a single viewpoint within a Homogeneous 3-Dimensional (3D) virtual environment. In preferred embodiments, the systems and methods are used as part of a virtual training environment where multiple participants are participating simultaneously. The methods and systems render multiple objects from multiple eye-points by creating custom projection matrix for each eye-point. Each rendered object is overlaid over the background and other images rendered with the standard eye-point projection matrix. Preferred embodiments use the same view matrix for all renderings.
1. A method for rendering a scene comprising:
rendering a background scene;
rendering a first model from an eye-point of a first viewer location using a standard projection matrix to form a first image;
identifying a second model to be rendered independently from the background scene and from an eye-point other than the eye-point of the first viewer location;
identifying an eye-point of a second viewer location that is different from the first viewer location to render the second model from;
computing an asymmetric projection matrix to render the second model from the eye-point of the second viewer location wherein the asymmetric projection matrix has an asymmetry to compensate for the eye-point of the second viewer location;
rendering the second model independently from the background scene using the asymmetric projection matrix to form a second image; and,
forming a composite image by overlaying the second image, the first image and the background scene.
2. The method of claim 1 , wherein the second model is tagged.
3. The method of claim 1 , wherein eye-points of five different viewer locations are used to render five different models.
4. The method of claim 1 , wherein a single view matrix is used to render both the first model and the second model.
5. The method of claim 1 , wherein the eye-point of a first viewer location is centered along a horizontal axis of the scene.
6. The method of claim 1 , further comprising an eye-point of a third viewer location wherein each eye-point is evenly spaced along a horizontal axis of the scene.
7. The method of claim 6 , wherein a horizontal spacing of a homogeneous screen space is used to evenly space each eye-point along the horizontal axis of the scene.
8. The method of claim 1 , wherein the identifying a second model step is performed by comparing a screen location of the second model relative to the eye-point of the first viewer location.
9. The method of claim 1 , further comprising moving the second model to a position that is a same distance from the eye-point of the first viewer location as the first model.
10. The method of claim 1 , wherein the background scene is rendered simultaneously with the first model and from the eye-point of the first viewer location using the standard projection matrix.
11. A non-transitory computer readable medium containing program instructions for rendering a three dimensional scene, wherein execution of the program instructions by one or more processors causes the one or more processors to carry out the method comprising:
rendering a background scene;
rendering a first model from an eye-point of a first viewer location using a standard projection matrix to form a first image;
identifying a plurality of models to be rendered independently from the background scene and from eye-points other than the eye-point of the first viewer location;
identifying a plurality of eye-points, each eye-point in the plurality of eye-points associated with a different viewer location than any other eye-point, to render the plurality of models from;
computing an asymmetric projection matrix for each eye-point in the plurality of eye-points wherein each asymmetric projection matrix has an asymmetry to compensate for a different eye-point in the plurality of eye-points;
rendering each model in the plurality of models independently from the background scene and from its respective identified eye-point with its respective asymmetric projection matrix to form a plurality of images; and,
forming a composite image by overlaying the plurality of images, the first image and the background scene.
12. The computer readable medium of claim 11 , wherein each model in the plurality of models is tagged.
13. The computer readable medium of claim 11 , wherein the plurality of eye-points is five or more.
14. The computer readable medium of claim 11 , wherein a single view matrix is used to render the first model and each model of the plurality of models.
15. The computer readable medium of claim 11 , wherein the eye-point of the first viewer location is centered along a horizontal axis of the scene.
16. The computer readable medium of claim 11 , wherein each eye-point is evenly spaced along a horizontal axis of the scene.
17. The computer readable medium of claim 16 , wherein a horizontal spacing of a homogeneous screen space is used to evenly space each eye-point along the horizontal axis of the scene.
18. The computer readable medium of claim 11 , wherein the identifying a second model step is performed by comparing a screen location of the second model relative to the eye-point of the first viewer location.
19. The computer readable medium of claim 11 , further comprising moving at least some of the models in the plurality of models to a position that is a same distance from the eye-point of the first viewer location as the first model.
20. The computer readable medium of claim 11 , wherein the background scene is rendered simultaneously with the first model and from the eye-point of the first viewer location using the standard projection matrix.