{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2023,10,25]],"date-time":"2023-10-25T16:11:41Z","timestamp":1698250301221},"reference-count":12,"publisher":"Wiley","issue":"1","license":[{"start":{"date-parts":[[2006,10,31]],"date-time":"2006-10-31T00:00:00Z","timestamp":1162252800000},"content-version":"vor","delay-in-days":5051,"URL":"http:\/\/onlinelibrary.wiley.com\/termsAndConditions#vor"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["J. Visual. Comput. Animat."],"published-print":{"date-parts":[[1993,1]]},"abstract":"<jats:title>Abstract<\/jats:title><jats:p>A three\u2010dimensional surface is a useful graphic representation of a two\u2010dimensional function which has been sampled on a regular grid. Shading the surface to simulate the effects of direct lighting makes visible small changes in the surface orientation, and enhances realism when the data represents a physical surface such as terrain. Shading interpolation calculations and surface patch generation techniques require the specification of a surface normal vector (or related slope information) at each sample point. These normal vectors are usually generated by averaging local data such as the normal vectors of the surfaces of a triangular mesh connecting the points. This paper describes a technique which uses Fourier filtering to generate normal vectors for two\u2010dimensional sampled data. Images and analysis of frequency spectra are included to show how this technique preserves detail which is lost using the averaging method. Performance figures show that this enhancement of detail in the final image can be achieved for only a small increase in computation time.<\/jats:p>","DOI":"10.1002\/vis.4340040106","type":"journal-article","created":{"date-parts":[[2006,11,17]],"date-time":"2006-11-17T14:28:14Z","timestamp":1163773694000},"page":"33-49","source":"Crossref","is-referenced-by-count":0,"title":["Normal vector generation for sampled data using fourier filtering"],"prefix":"10.1002","volume":"4","author":[{"given":"Michael E.","family":"Goss","sequence":"first","affiliation":[]},{"given":"Ivor P.","family":"Page","sequence":"additional","affiliation":[]}],"member":"311","published-online":{"date-parts":[[2006,10,31]]},"reference":[{"key":"e_1_2_1_2_2","doi-asserted-by":"publisher","DOI":"10.1109\/T-C.1971.223313"},{"key":"e_1_2_1_3_2","doi-asserted-by":"publisher","DOI":"10.1145\/360825.360839"},{"key":"e_1_2_1_4_2","volume-title":"Fundamentals of Three\u2010Dimensional Computer Graphics","author":"Watt Alan","year":"1989"},{"key":"e_1_2_1_5_2","volume-title":"Computer Graphics: Principles and Practice","author":"Foley James D.","year":"1990"},{"key":"e_1_2_1_6_2","volume-title":"Digital Signal Processing","author":"Oppenheim Alan V.","year":"1975"},{"key":"e_1_2_1_7_2","volume-title":"Digital Filters: Analysis and Design","author":"Antoniou Andreas","year":"1979"},{"key":"e_1_2_1_8_2","volume-title":"Mathematics for Scientists and Engineers","author":"Jeffrey Alan","year":"1990"},{"key":"e_1_2_1_9_2","unstructured":"William H.Press Brian P.Flannery Saul A.TeukolskyandWilliam T.Vetterling Numerical Recipes in C: The Art of Scientific Computing Cambridge UP Cambridge England 1988."},{"key":"e_1_2_1_10_2","doi-asserted-by":"publisher","DOI":"10.1007\/978-1-4612-3784-6_1"},{"key":"e_1_2_1_11_2","volume-title":"The FFT: Fundamentals and Concepts","author":"Ramirez Robert W.","year":"1985"},{"key":"e_1_2_1_12_2","volume-title":"Digital Elevation Models","author":"Elassal Atef A.","year":"1983"},{"key":"e_1_2_1_13_2","unstructured":"United States Geological Survey Crater Lake West Quadrangle Oregon\u2010Klamath Co. 7.5 minute series topographic map 1 : 24000 scale 1985."}],"container-title":["The Journal of Visualization and Computer Animation"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/api.wiley.com\/onlinelibrary\/tdm\/v1\/articles\/10.1002%2Fvis.4340040106","content-type":"unspecified","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/pdf\/10.1002\/vis.4340040106","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2023,10,24]],"date-time":"2023-10-24T18:48:57Z","timestamp":1698173337000},"score":1,"resource":{"primary":{"URL":"https:\/\/onlinelibrary.wiley.com\/doi\/10.1002\/vis.4340040106"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1993,1]]},"references-count":12,"journal-issue":{"issue":"1","published-print":{"date-parts":[[1993,1]]}},"alternative-id":["10.1002\/vis.4340040106"],"URL":"https:\/\/doi.org\/10.1002\/vis.4340040106","archive":["Portico"],"relation":{},"ISSN":["1049-8907","1099-1778"],"issn-type":[{"value":"1049-8907","type":"print"},{"value":"1099-1778","type":"electronic"}],"subject":[],"published":{"date-parts":[[1993,1]]}}}