{"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 – ATI vs NVIDIA"},"content":{"rendered":"

Really ATI has some problems with OpenGL. Now I’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

<\/center><\/p>\n

And on my second CG, a nVidia 6600gt (forceware 91.31), the soft shadows are as follows:<\/p>\n

<\/center><\/p>\n

The GLSL shaders are the same, a 5×5 bluring kernel, with a shadow map (or depth map as you want) of 1024×1024 (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

<\/center><\/p>\n

and for the 6600gt:<\/p>\n

<\/center><\/p>\n

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.
\nI’m not satisfied by this explanation but it’s the only I see for the moment.<\/p>\n

This kind of problem shows how it’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":"

Really ATI has some problems with OpenGL. Now I’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 … Continue reading Depth Map Filtering – ATI vs NVIDIA<\/span> »<\/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":[],"aioseo_head":"\n\t\t\n\t\n\t\n\t\n\t\n\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t\n\t\t