{"id":66,"date":"2006-08-06T18:00:23","date_gmt":"2006-08-06T17:00:23","guid":{"rendered":"http:\/\/www.ozone3d.net\/blogs\/lab\/?p=66"},"modified":"2009-07-22T16:56:47","modified_gmt":"2009-07-22T15:56:47","slug":"depth-map-filtering-ati-vs-nvidia","status":"publish","type":"post","link":"https:\/\/www.ozone3d.net\/blogs\/lab\/20060806\/depth-map-filtering-ati-vs-nvidia\/","title":{"rendered":"Depth Map Filtering &#8211; ATI vs NVIDIA"},"content":{"rendered":"<p>Really ATI has some problems with OpenGL. Now I&#8217;m working on soft shadows and my tmp devstation has a Radeon X700 (not the top-notch I know but an enough powerful CG). With my X700 (Catalyst 6.6) the soft shadow edges are rendered as follows:<\/p>\n<p><center><img decoding=\"async\" src=\"public\/200608\/ATIX700_5x5_1024dmap_linear_partial.jpg\" \/><\/center><\/p>\n<p>And on my second CG, a nVidia 6600gt (forceware 91.31), the soft shadows are as follows:<\/p>\n<p><center><img decoding=\"async\" src=\"public\/200608\/nv6600gt_5x5_1024dmap_linear_partial.jpg\" \/><\/center><\/p>\n<p>The GLSL shaders are the same, a 5&#215;5 bluring kernel, with a shadow map (or depth map as you want) of 1024&#215;1024 (via a FBO) with a linear filtering. Now if I set the nearest filtering mode, I get the following results for the X700:<\/p>\n<p><center><img decoding=\"async\" src=\"public\/200608\/ATIX700_5x5_1024dmap_nearest_partial.jpg\" \/><\/center><\/p>\n<p>and for the 6600gt:<\/p>\n<p><center><img decoding=\"async\" src=\"public\/200608\/nv6600gt_5x5_1024dmap_nearest_partial.jpg\" \/><\/center><\/p>\n<p>It seems as if the Radeon GPU has a bug in the filtering module when the gpu has to apply a linear filter on a depth map. Very strange.<br \/>\nI&#8217;m not satisfied by this explanation but it&#8217;s the only I see for the moment.<\/p>\n<p>This kind of problem shows how it&#8217;s important for a graphics developer to have at least 2 workstations, one with a nVidia board and the other with an ATI CG. I tell you, realtime 3D is made of blood, sweat and screams! :winkhappy:<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Really ATI has some problems with OpenGL. Now I&#8217;m working on soft shadows and my tmp devstation has a Radeon X700 (not the top-notch I know but an enough powerful CG). With my X700 (Catalyst 6.6) the soft shadow edges are rendered as follows: And on my second CG, a nVidia 6600gt (forceware 91.31), the soft shadows are as follows: The GLSL shaders are the &hellip; <a href=\"https:\/\/www.ozone3d.net\/blogs\/lab\/20060806\/depth-map-filtering-ati-vs-nvidia\/\" class=\"more-link\">Continue reading <span class=\"screen-reader-text\">Depth Map Filtering &#8211; ATI vs NVIDIA<\/span> <span class=\"meta-nav\">&raquo;<\/span><\/a><\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[9,8],"tags":[22,202,203,51,201],"class_list":["post-66","post","type-post","status-publish","format-standard","hentry","category-opengl","category-programming","tag-ati","tag-depth-map","tag-filtering","tag-nvidia","tag-soft-shadow"],"aioseo_notices":[],"views":784,"_links":{"self":[{"href":"https:\/\/www.ozone3d.net\/blogs\/lab\/wp-json\/wp\/v2\/posts\/66","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.ozone3d.net\/blogs\/lab\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.ozone3d.net\/blogs\/lab\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.ozone3d.net\/blogs\/lab\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.ozone3d.net\/blogs\/lab\/wp-json\/wp\/v2\/comments?post=66"}],"version-history":[{"count":0,"href":"https:\/\/www.ozone3d.net\/blogs\/lab\/wp-json\/wp\/v2\/posts\/66\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.ozone3d.net\/blogs\/lab\/wp-json\/wp\/v2\/media?parent=66"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.ozone3d.net\/blogs\/lab\/wp-json\/wp\/v2\/categories?post=66"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.ozone3d.net\/blogs\/lab\/wp-json\/wp\/v2\/tags?post=66"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}