Method and apparatus for evaluating sight distance

A method of sight distance analysis comprising:

• acquiring a scene-graph representation comprising three dimensional entities;
• acquiring at least one three dimensional object representation within the environment of said scene graph;
• acquiring a target object representation;
• selecting at least one camera position;
• positioning said acquired target object representation in said scene graph representation at a distance from said selected at least one camera position;
• computing an axis aligned bounding box for said positioned target object;
• enlarging said computed bounding box by a buffer value to define an area;
• rendering a photorealistic image of the defined area with said positioned target object turned on;
• rendering a photorealistic image of the defined area with said positioned target object turned off;
• and
• calculating an RGB pixel difference between said rendered photorealistic image with said target object turned on and said rendered photorealistic image with said target object turned off, thereby determining a visibility factor for said positioned target object.

A method of sight distance analysis comprising:

• acquiring a scene-graph representation comprising three dimensional entities;
• acquiring at least one three dimensional object representation within the environment of said scene graph;
• acquiring a target object representation;
• selecting at least one camera position;
• positioning said acquired target object representation in said scene graph representation at a distance from said selected at least one camera position;
• computing an axis aligned bounding box for said positioned target object;
• enlarging said computed bounding box by a buffer value to define an area;
• rendering a photorealistic image of the defined area with said positioned target object turned on;
• calculating a spatial frequency of said photorealistic image of the defined area with said positioned target object turned on;
• rendering a photorealistic image of the defined area with said positioned target object turned off;
• calculating a spatial frequency of said photorealistic image of the defined area with said positioned target object turned off;
• and
• generating a spatial frequency visibility factor responsive to the difference between said calculated spatial frequency with said target object turned on and said target object turned off, thereby determining a visibility factor for said positioned target object.

A computing system for sight distance analysis comprising a computer and a monitor in communication therewith, said computer arranged to:

• acquire a scene-graph representation comprising three dimensional entities;
• acquire at least one three dimensional object representation within said scene graph environment;
• acquire a target object representation;
• select at least one camera position;
• position said acquired target object representation in said scene graph representation at a distance from said selected at least one camera position;
• render said target object without rendering said at least one three dimensional object representation intervening between said observer and said target object;
• calculate a metric of said target object rendered without said intervening at least one three dimensional object representation;
• render said target object while rendering said at least one three dimensional object representation intervening between said observer and said target object;
• calculate a metric of said target object rendered with said intervening at least one three dimensional object representation;
• and
• determine a visibility factor as a function of the difference between said calculated metric of said target object rendered without said intervening at least one three dimensional object representation and said calculated metric of said target object rendered with said intervening at least one three dimensional object representation.

A computing system for sight distance analysis comprising a computer and a monitor in communication therewith, said computer being operative to:

• acquire a scene-graph representation comprising three dimensional entities;
• acquire at least one three dimensional object representation within said scene graph environment;
• acquire a target object representation;
• select at least one camera position;
• position said acquired target object representation in said scene graph representation at a distance from said selected at least one camera position;
• compute an axis aligned bounding box for said positioned target object;
• enlarge said computed bounding by a buffer value to define an area;
• render a photorealistic image of the defined area with said positioned target object turned on;
• render a photorealistic image of the defined area with said positioned target object turned off;
• and
• calculate an RGB pixel difference between said rendered photorealistic image with said target object turned on and said rendered photorealistic image with said target object turned off to thereby determine a visibility factor for said positioned target object representation.

A computing system for sight distance analysis comprising a computer and a monitor in communication therewith, said computer being operative to:

• acquire a scene-graph representation comprising three dimensional entities;
• acquire at least one three dimensional object representation within said scene graph environment;
• acquire a target object representation;
• select at least one camera position;
• position said acquired target object representation in said scene graph representation at a distance from said selected at least one camera position;
• compute an axis aligned bounding box for said positioned target object;
• enlarge said computed bounding box by a buffer value to define an area;
• render a photorealistic image of the defined area with said positioned target object turned on;
• calculate a spatial frequency of said photorealistic image of the defined area with said positioned target object turned on;
• render a photorealistic image of the defined area with said positioned target object turned off;
• calculate a spatial frequency of said photorealistic image of the defined area with said positioned target object turned off;
• and
• generate a spatial frequency visibility factor responsive to the difference between said calculated spatial frequency with said target object turned on and said target object turned off to thereby determine a visibility factor for said positioned target object representation.