{"comment":{"created_at":"2011-10-09T20:37:40Z","body":"[mar_rud] I don't see how #506 would help here, because still resolution would be computed based on variable bbox. As I understand it's value it is rendered map units per pixel and if image width/height doesn't change while BoundsClipping, used extend in equation should be also based on requested bounds, not after clipping. Also query passed to gdal input would still contain buffer in its bbox extend, because it generally should (in vector layers it is needed to catch near edge features), but raster doesn't need this and adding unbuffered bbox to query could increase a little rendering speed for those using buffer_size (probably not more than 1-2%).\r\n\r\nAlso in agg_renderer.cpp destination raster size after scaling is computed using something like that (removed inconsistent rounding double->int for clarity):\r\n{{{\r\nt_(m.getWidth(),m.getHeight(),m.getCurrentExtent(),offset_x,offset_y).\r\n....\r\nEnvelope<double> ext=t_.forward(raster->ext_);\r\nImageData32 target(ext.width(),ext.height());\r\n}}}\r\nand in gdal_featureset.cpp it is estimated as:\r\n{{{\r\nint im_width = q.resolution() * intersect.width();\r\nint im_height = q.resolution() * intersect.height();\r\n}}}\r\nand for this to work, resolution should be equal m.getWidth()/m.getCurrentExtent().width() (in trunk same but for both x/y like shown earlier). Besides only gdal plugin is using this property for anything.","updated_at":"2011-10-09T20:37:40Z","url":"https://api.github.com/repos/artemp/trac2github/issues/comments/2340221","id":2340221,"user":{"avatar_url":"https://secure.gravatar.com/avatar/941f68386168a8a6b60f2529a7830af7?d=https://a248.e.akamai.net/assets.github.com%2Fimages%2Fgravatars%2Fgravatar-140.png","url":"https://api.github.com/users/artemp","id":59056,"login":"artemp"}},"action":"created","issue":{"number":503,"created_at":"2011-10-09T20:37:37Z","pull_request":{"diff_url":null,"patch_url":null,"html_url":null},"body":"Near the scale where we reach the resolution limits of an input raster we avoid having GDAL pre-scale the image, so that upsampling can be done within the RasterSymbolizer.\r\n\r\nThis is currently done here: http://trac.mapnik.org/browser/trunk/plugins/input/gdal/gdal_featureset.cpp#L139\r\n\r\nBut when map buffers are used it is likely that`im_width != width` is at, or past, the resolution limit of the image and a GDAL pre-scaled image is chosen that is too small.","comments":4,"title":"Map buffer_size not accounted for within GDAL plugin scaling logic","updated_at":"2011-10-09T20:37:40Z","url":"https://api.github.com/repos/artemp/trac2github/issues/503","id":1858739,"assignee":null,"milestone":{"number":10,"created_at":"2011-10-09T19:01:24Z","due_on":"1970-01-01T09:21:08Z","title":"0.7.1","creator":{"avatar_url":"https://secure.gravatar.com/avatar/941f68386168a8a6b60f2529a7830af7?d=https://a248.e.akamai.net/assets.github.com%2Fimages%2Fgravatars%2Fgravatar-140.png","url":"https://api.github.com/users/artemp","id":59056,"login":"artemp"},"url":"https://api.github.com/repos/artemp/trac2github/milestones/10","open_issues":1,"closed_issues":5,"description":"= Mapnik 0.7.1 =\r\n\r\nThe 0.7.1 is a bugfix release, but also includes some new PNG output features.\r\n\r\nUntil tagging, source is here (after which this branch will be removed):\r\n{{{\r\nsvn co http://svn.mapnik.org/branches/0.7.1-dev/\r\n}}}\r\n\r\nRelease page: wiki:Release0.7.1\r\n\r\nCHANGELOG: source:tags/release-0.7.1/CHANGELOG\r\n\r\nUsage, either via Python or XML stylesheets should be fully compatible with the 0.6.x series.\r\n\r\n== Plugins ==\r\n * #500 - postgis: fixing full support for schemas in postgis plugin\r\n * #502  - gdal: bug in gdal scaling when using map buffer leading to poor image scaling\r\n * #504  - shapefile: support for pointz\r\n\r\n== Python ==\r\n * No changes\r\n\r\n== Core ==\r\n * #508 - image symbolizers: made optional use of width/height/type attributes in LinePatternSymbolizer and PolygonPatternSymbolizer to match PointSymbolizer\r\n * #512 - gamma: preservation of AA across symbolizers if gamma modified on PolygonSymbolizer\r\n * #484  - scons: applied preferential sorting to lib/inc directories to ensure linking first to source compiled libs in /usr/local/lib (like icu and boost) if duplicate libraries are in /usr/lib\r\n * Raster Fixes/Enhancements\r\n  * #522 - fix colors in huge png256 output\r\n  * #475 - fixed small shift in raster output\r\n  * #477 - added new hextree based quantization\r\n  * #477 - new png image compression options","state":"open"},"closed_at":null,"user":{"avatar_url":"https://secure.gravatar.com/avatar/941f68386168a8a6b60f2529a7830af7?d=https://a248.e.akamai.net/assets.github.com%2Fimages%2Fgravatars%2Fgravatar-140.png","url":"https://api.github.com/users/artemp","id":59056,"login":"artemp"},"html_url":"https://github.com/artemp/trac2github/issues/503","labels":[{"name":"GDAL_Input_Driver","url":"https://api.github.com/repos/artemp/trac2github/labels/GDAL_Input_Driver","color":"FFFFFF"}],"state":"open"},"legacy":{"issue_id":1858739,"comment_id":2340221}}