Object visibility control for ray tracing

• US 6,956,570 B2
• Filed: 06/27/2001
• Issued: 10/18/2005
• Est. Priority Date: 06/27/2001
• Status: Expired due to Term

• Current Assignee: Mind Fusion, LLC (Ascend Innovation Management, LLC)
• Original Assignee: Believe, Inc.
• Inventors: Munshi, Aaftab A.
• Primary Examiner(s): Nguyen, Phu K.
• Application Number:
  US09/894,225
• Publication Number:
  US 20030001842A1
• Time in Patent Office: 1,574 Days
• Field of Search: 345/156, 345/179, 345/419, 345/426, 345/505, 345/536, 345/810, 345/835, 345/427, 345/441, 345/584, 345/589, 345/615, 345/629, 710/5
• US Class Current: 345/426
• CPC Class Codes: G06T 15/06 Ray-tracing
• CPC Class Codes: G06T 15/40 Hidden part removal

Abstract

A computer graphics method and apparatus allows designer control over the rendering of objects and scenes, in a rendering system using ray tracing for example. A modeling system is adapted to accept rules for controlling how certain objects affect the appearance of certain other objects. In a ray tracing implementation, rules are specified by ray type and can be specified as either “including” all but certain objects or “excluding” specific objects for any given object. A rendering system extracts these rules from a bytestream or other input including other graphics data and instructions, and populates lists for internal use by other components of the rendering system. A ray tracer in the rendering system is adapted to consult the list when performing ray tracing, so as to enforce the rendering control specified by the content creator when the objects and scene are rendered.

Claims

1. A graphics apparatus, comprising:

a rendering system that renders an object in response to a graphics input, the graphics input including object visibility rules, the rendering system constraining the rendering of the object in accordance with the object visibility rules, wherein the object visibility rules allow a graphics designer to control how certain objects or lights, or both, affect the appearance of other objects or lights, or both,

wherein a rendering system includes a ray tracer, the object visibility rules specifying a relationship between light sources and certain rays, the ray tracer looking up a rule associated with one of the light sources when processing the certain rays for the light source.

2. A graphics apparatus according to claim 1, wherein the certain rays include rays originating from the light source and potentially intersecting the object.

3. A graphics apparatus, comprising:

a rendering system that renders an object in response to a graphics input, the graphics input including object visibility rules, the rendering system constraining the rendering of the object in accordance with the object visibility rules, wherein the object visibility rules allow a graphics designer to control how certain objects or lights, or both, affect the appearance of other objects or lights, or both,

wherein the rendering system includes a ray tracer, the object visibility rules specifying a relationship between the object and certain rays, the ray tracer looking up a rule associated with the object when processing the certain rays for the object, and

wherein the ray tracer constructs a ray tree associated with the object in accordance with the object visibility rules.

4. A plug-in application for a modeling system that constructs object visibility rules in response to user input, the object visibility rules being supplied to a rendering system in a graphics input from the modeling system, the rendering system rendering an object in response to the graphics input, the rendering system constraining the rendering of the object in accordance with the object visibility rules, wherein the object visibility rules allow a graphics designer to control how certain objects or lights, or both, affect the appearance of other objects or lights, or both,

wherein the rendering system includes a ray tracer, the object visibility rules specifying a relationship between light sources and certain rays, the ray tracer looking up a rule associated with one of the light sources when processing the certain rays for the light source.

5. A plug-in application according to claim 4, wherein the certain rays include rays originating from the light source and potentially intersecting the object.

6. A plug-in application for a modeling system that constructs object visibility rules in response to user input, the object visibility rules being supplied to a rendering system in a graphics input from the modeling system, the rendering system rendering an object in response to the graphics input, the rendering system constraining the rendering of the object in accordance with the object visibility rules, wherein the object visibility rules allow a graphics designer to control how certain objects or lights, or both, affect the appearance of other objects or lights, or both,

wherein the ray tracer constructs a ray tree associated with the object in accordance with the object visibility rules.

7. A graphics apparatus comprising:

a scene server that receives a graphics input specifying a plurality of objects and extracts object visibility rules from the graphics input; and

a ray tracer coupled to the scene server that determines intersections of rays with

certain of the plurality of objects included in a scene, the ray tracer receiving the object visibility rules and constraining the ray intersection determination in accordance therewith, wherein the object visibility rules allow a graphics designer to control how certain objects or lights, or both, affect the appearance of other objects or lights, or both,

wherein the ray tracer constructs ray trees associated with the certain objects and the intersections, the ray tracer constraining objects to be included in the ray trees in accordance with the object visibility rules.

8. A graphics apparatus according to claim 7, further comprising a shader coupled to the ray tracer for determining colors associated with the ray trees.

9. A graphics apparatus comprising:

means for receiving a graphics input specifying a plurality of objects;

means for extracting object visibility rules from the graphics input; and

means for determining intersections of rays with certain of the plurality of objects in a scene, the determining means including means for receiving the object visibility rules and means for constraining the ray intersection determination in accordance therewith, wherein the object visibility rules allow a graphics designer to control how certain objects or lights, or both, affect the appearance of other objects or lights, or both,

wherein the determining means further includes means for constructing ray trees associated with the certain objects and the intersections, the constraining means constraining objects included in the ray trees in accordance with the object visibility rules.

10. A graphics apparatus according to claim 9, further comprising means for determining colors associated with the ray trees.

11. A graphics method comprising:

receiving a graphics input specifying a plurality of objects;

extracting object visibility rules from the graphics input; and

determining intersections of rays with certain of the plurality of objects in a scene, the determining step including receiving the object visibility rules and constraining the ray intersection determination in accordance therewith, wherein the object visibility rules allow a graphics designer to control how certain objects or lights, or both, affect the appearance of other objects or lights, or both,

wherein the determining step further includes constructing ray trees associated with the certain objects and the intersections, the constraining step including constraining objects included in the ray trees in accordance with the object visibility rules.

12. A graphics apparatus according to claim 11, further comprising determining colors associated with the ray trees.