Push-tumble three dimensional navigation system

A method of three-dimensional viewing or navigating, comprising:

• generating a two-dimensional input;
• panning a view of a model according to the two-dimensional input;
• automatically zooming the view according to the two-dimensional input;
• and
• automatically tumbling the view according to the two-dimensional input, where said panning, zooming, and tumbling are relative to a fixed point in the space of the model.

A data structure used to view or navigate a surface of a three-dimensional model in a three-dimensional space, comprising:

• a moving view vector comprising a view direction in the three-dimensional space and having a constant view length;
• a moving view point defining a position of the view vector in the three-dimensional space;
• and
• a moving focus point constrained to the surface, defined by said moving view point and said view vector, where said view vector ends at the focus point and said focus point and said view position are the constant view length apart.

A method of interactively navigating or manipulating a view of a three-dimensional model, comprising:

• viewing a surface of the model from an initial view point with an initial view direction;
• generating a single two-dimensional vector by moving a mouse;
• translating, according to the vector, the initial view point to a next view point in a plane normal to the view direction and intersecting the initial view point;
• automatically finding a point of the surface that is closest to the next view point;
• and
• automatically setting a next view direction to a direction from the next view point to the closest surface point.

A method of interactively navigating or manipulating a view of a three-dimensional model, comprising:

• viewing a surface from an initial view point with an initial view direction;
• generating a single two-dimensional vector by moving a mouse;
• automatically translating, according to the vector, the initial view point to a next view point in a plane normal to the view direction and intersecting the initial view point;
• automatically finding a point of the surface that is closest to the next view point by casting rays from the next view point with a three-dimensional spread in the direction of the initial direction, determining intersection points where the rays intersect the surface, finding distances between the intersection points and the next view point, and selecting the point with the smallest distance;
• automatically setting a next view direction to a direction from the next view point to the closest surface point, wherein the next view direction is set to the direction of a ray corresponding to the point with the smallest distance;
• and
• automatically translating the next view point toward or away from the closest surface point, along the next view direction, to a location that is a same distance from the surface as the initial view point.

An apparatus for interactively manipulating a view of a three-dimensional model, comprising:

• a viewing unit viewing a surface from an initial view point with an initial view direction;
• an input unit generating a single two-dimensional vector;
• and
• a computing unit performing a process comprising:
• translating, according to the vector, the initial view point to a next view point in a plane normal to the view direction and intersecting the initial view point;
• finding a point of the surface that is closest to the next view point;
• setting a next view direction to a direction from the next view point to the closest surface point;
• and
• translating the next view point along the next view direction.

A method, comprising:

• moving a mouse in two dimensions;
• translating a three dimensional view to a new position in accordance with the mouse movement;
• determining an average distance from the new position to points of a model surface;
• and
• automatically orienting the view towards the model surface based on the average distance.

An apparatus for three-dimensional viewing or navigating, the apparatus comprising:

• a processing unit performing a process, the process comprising:
• automatically moving a camera, according to interactively generated two-dimensional data, from a current position relative to the model, to a new position relative to the model;
• and
• automatically facing, at both positions, the camera to the model at a distance from a surface of the model.