Invalidity dossier
US 6624811
System, method and article of manufacture for decomposing surfaces using guard curves and reversed stitching
Current assignee: Nvidia Corp
Added 9/23/2026, 1:47:13 PM
Active provider: DeepSeek · deepseek-flash
Patent summary
Title, assignee, inventors, filing/issue dates, abstract, and a plain-language overview of the claims.
Patent Overview — US 6624811 B1
Title: System, method and article of manufacture for decomposing surfaces using guard curves and reversed stitching
Patent number: US 6624811 B1
Application number: US09/652,866
Inventors: Henry P. Moreton; Justin Legakis
Assignee: Nvidia Corp (original assignee); listed current assignee Nvidia Corp
Priority/filing date: 2000-08-31
Publication (grant) date: 2003-09-23
Legal status (as listed): Expired – Lifetime, adjusted expiration 2021-05-17. Google notes legal status is an assumption, not a legal conclusion.
Classification: G06T17/20 (finite element generation, e.g. wire-frame surface description, tessellation), under G06T17/00 (3D modelling for computer graphics)
Purpose: The invention relates to computer graphics, specifically constructing primitives for rendering in a graphics pipeline. Tessellation decomposes a surface into simpler primitives (triangles or quadrilaterals) for rendering. A stated problem with conventional forward differencing is accumulation of round-off error, causing mismatched values along shared patch edges and rendering artifacts such as pixel dropouts, double hits and/or cracking.
Plain-language scope: A patch is received; strip curves are defined in a first predetermined direction, defining areas to be decomposed into primitives. At least one guard curve is generated along the ends of the strip curves, in a second predetermined direction perpendicular to the first in parameter space, so the guard curve is determined consistent with curves on edges/boundaries of adjacent patches. This is said to prevent vertex mismatches and ensure decomposition consistent with an adjacent patch. Areas may be decomposed using forward differencing. A reversed strip curve may be generated in a third direction parallel and opposite the first, with the resulting area tessellated using reverse stitching. Guard curve count, spacing and length may depend on vertex memory size; guard curves may carry position, normal, color or texture values. The excerpt also describes a forward differencing engine with memory banks, adders, optional cross-product module and guard curve memory banks, plus triangular-patch handling.
Source: https://patents.google.com/patent/US6624811/en
What the excerpt does not establish: The complete claim set, full specification text, tables, drawings, examiner citations, or any prior-art references are not reproduced here, so claim scope cannot be fully verified. No litigation, ownership-transfer, validity, or prior-art conclusions are drawn. Text is excerpted; details may be omitted.
Generated 10/1/2026, 9:52:49 PM
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Litigation summary
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PTAB challenges
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Assignment history
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Prior art
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Obviousness
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Extensions
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Derivative works
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