# US 2011/0267342 A1 · Method and apparatus for evaluating sight distance > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2011/0267342 A1 - Document ID: US20110267342A1 - Status: Published application - Kind: A1 - Application number: 13/179,527 - Filed: 2011-07-10 - Published: 2011-11-03 - Earliest claimed: 2005-10-04 - Assignees: Rdv Systems Ltd. - Inventors: Nathan ELSBERG; Alex HAZANOV - Web page: https://patentgrep.com/patent/US20110267342A1 ## CPC - G06F 30/13: Architectural design, e.g. computer-aided architectural design [CAAD] related to design of buildings, bridges, landscapes, production plants or roads - G06T 15/00: Three-dimensional [3D] image rendering - G06T 17/05: Geographic models - G06T 19/003: {Navigation within 3D models or images} - G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N) - G06T: IMAGE DATA PROCESSING OR GENERATION, IN GENERAL ## Abstract 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 scene graph environment; acquiring a target object representation; selecting at least one camera position; positioning the acquired target object representation in the scene graph representation at a distance from the selected at least one camera position; and determining a visibility factor for the positioned target object representation. ## Claims ### Claim 1 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; and determining a visibility factor for said positioned target object representation. ### Claim 2 (depends on 1) A method of sight distance analysis according to claim 1, wherein said acquired at least one three dimensional object representation is constituted of a light detection and ranging (LIDAR) model. ### Claim 3 (depends on 1) A method of sight distance analysis according to claim 1, wherein said determining a visibility factor comprises: counting the number of pixels attributed to said positioned target object representation when said target object representation is rendered alone; counting the number of pixels attributed to said positioned target object representation when said three dimensional entities are rendered; and determining the difference between said counted pixels when said target object representation is rendered alone and when said three dimensional entities are rendered. ### Claim 4 (depends on 1) A method according to claim 1 further comprising: animating said selected camera position along a path; and generating a report for a plurality of points along said path, said report comprising observer position, target position and visibility factor for said target object at each of said plurality of points, wherein said visibility factor is a function of transparency of said acquired at least one three dimensional object representation within said scene graph environment. ### Claim 5 (depends on 4) A method of sight distance analysis according to claim 4, wherein said scene-graph representation is of an infrastructure, and said distance is dynamically calculated along said animation path responsive to at least one of a current speed, incline of said infrastructure and braking coefficient. ### Claim 6 (depends on 1) A method of sight distance analysis according to claim 1, wherein said distance is user determined. ### Claim 7 (depends on 1) A method of sight distance analysis according to claim 1, wherein said distance is calculated responsive to at least one of a defined speed and a parameter of said representation. ### Claim 8 (depends on 1) A method of sight distance analysis according to claim 1, wherein said determining a visibility factor for said positioned target object representation comprises: rendering said target object representation without rendering said at least one three dimensional object representation intervening between said observer and said target object representation; calculating a metric of said target object representation rendered without said intervening at least one three dimensional object representation; rendering said target object representation while rendering said at least one three dimensional object representation intervening between said observer and said target object representation; calculating a metric of said target object representation rendered with said intervening at least one three dimensional object representation; and determining a visibility factor as a function of the difference between said calculated metric of said target object representation rendered without said intervening at least one three dimensional object representation and said calculated metric of said target object representation rendered with said intervening at least one three dimensional object representation. ### Claim 9 (depends on 1) A method of sight distance analysis according to claim 1, wherein said determining a visibility factor for said positioned target object comprises: 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. ### Claim 10 (depends on 1) A method of sight distance analysis according to claim 1, wherein said determining a visibility factor for said positioned target object comprises: 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. ### Claim 11 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; and determine a visibility factor for said positioned target object representation. ### Claim 12 (depends on 11) A computing system for sight distance analysis according to claim 11, wherein said acquired at least one three dimensional object representation is constituted of a light detection and ranging (LIDAR) model. ### Claim 13 (depends on 11) A computing system for sight distance analysis according to claim 11, wherein said determine a visibility factor comprises: count the number of pixels attributed to said positioned target object when said target object is rendered alone; count the number of pixels attributed to said positioned target object when said three dimensional entities are rendered; and determine the difference between said counted pixels when said target object is rendered alone and when said three dimensional entities are rendered. ### Claim 14 (depends on 11) A computing system for sight distance analysis according to claim 11, wherein said computer is further operative to: animate said selected camera position along a path; and generate a report for a plurality of points along said path, said report comprising observer position, target position and visibility factor for said target object at each of said plurality of points, wherein said visibility factor is a function of transparency of said acquired at least one three dimensional object representation within said scene graph environment. ### Claim 15 (depends on 14) A computing system for sight distance analysis according to claim 14, wherein said scene-graph representation is of an infrastructure, and said distance is dynamically calculated along said animation path responsive to at least one of a current speed, incline of said infrastructure and braking coefficient. ### Claim 16 (depends on 14) A computing system for sight distance analysis according to claim 14, wherein said scene-graph representation is of an infrastructure and wherein said computer is further operative to: dynamically calculate said distance along said animation path responsive to at least one of a current speed, incline of said infrastructure and a braking coefficient. ### Claim 17 (depends on 11) A computing system for sight distance analysis according to claim 11, wherein said determining a visibility factor for said positioned target object comprises: 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. ### Claim 18 (depends on 11) A computing system for sight distance analysis according to claim 11, wherein said determining a visibility factor for said positioned target object comprises: 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. ### Claim 19 (depends on 11) A computing system for sight distance analysis according to claim 11, wherein said determine a visibility factor for said positioned target object comprises: 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. ### Claim 20 A method of sight distance analysis comprising: acquiring an infrastructure as a scene-graph comprising three dimensional entities; acquiring a nominal location for a moving observer in relation to a path on said infrastructure; acquiring a distance to a target, said target being maintained at said distance from said moving observer; calculating for a plurality of points along said path on said infrastructure a straight line between said moving observer and said target; defining a 2 dimensional polyline representation of a visual intrusion zone; and projecting said visual intrusion zone on a representation of said scene-graph.