Stefan wrote: "mhm.. the idea was to put in "Generate" tools that generate new features using (pure??) geometry operations. Here, one should only optain geometries - i.e. features without attributes.
The analysis section should involve more complex functions that generate new and modify features which also include attribute operations/analysis." and Stefan also wrote: "excactly. the primary idea is to select/extract features from an existing set." Would anyone object to having a written policy for developers based on what Stefan said? (I'm not talking about forcing developers to follow this policy, I'm just saying the policy could be a suggestion for developers.) The Sunburned Surveyor On 8/27/07, Stefan Steiniger <[EMAIL PROTECTED]> wrote: > thanx for your comments Michael and Martin. > > now my points below > > Michaël Michaud schrieb: > > Hi Uwe, > > > > Classifying plugins under Tools menu is really a hard job and some > > inconsistencies may come from a lack of coordination among developpers. > > I'll try to help with my limited knowledge of those functions > > > >> 1. What is the different between Tools>Analysis and Tools>Queries? > >> > >> > > I think queries never modify features, only select some of them. > excactly. the primary idea is to select/extract features from an > existing set. > > > > >> 2. Buffer is (one time) under Tools>Generate but Union (one Layer) is > >> under Tools>Analysis? > >> > >> > > IMHO, this is not very consistent > mhm.. the idea was to put in "Generate" tools that generate new features > using (pure??) geometry operations. Here, one should only optain > geometries - i.e. features without attributes. > > The analysis section should involve more complex functions that generate > new and modify features which also include attribute operations/analysis. > > SIGLE had actually a nice approach with a menu for "one-layer" and > "two-layer" ops. But this may also lead to some duplications. > > on the D-P question had Martin already a good answer. (Note, another > term for the Douglas Poiker (or Peucker) Simplification would be Point > Removal, but D-P specifies the algorithm. Other point removal > algorithms exists as well such as the Visvalingam algorithm or Bend-Simplfy) > > [wow.. when google-ing for bend-simplify i found this presentation on > GIS for military analysis... > http://www.dodccrp.org/events/12th_ICCRTS/CD/html/presentations/006.pdf > ..scarry.. ] > > stefan > > > > >> 3. Is there a reason why we have different notations (for example): > >> Source, source layer, Layer A, Layer, Source Layer? > >> > >> > > I saw that where A and B are used, they are referred in the explanation > > panel "select A.*, B.*..." which may be the reason. There may be some > > situations where layers have symmetric roles (like overlays), and others > > where a layer has a special role (source, target, reference), like > > attribute transfer. > > > >> 4. What is "Simplify D - P"? > >> > >> > > Simplify Douglas Peucker : a simplification algorithm (Stefan can > > surely explain that better than I) > > > >> 5. What is "Simplify (preserve topology)"? > >> > >> > > Simplify (preserve topology), applied to a network, preserve connections > > between linestrings (maybe Simplify D-P don't, I did not try). > > Sadly, topology is not preserved for a planar graph represented as > > polygons touching each others > > > >> 6. Thank you for your help! > >> > >> > >> > >> 1 = Tools>Analysis>Geometry Functions (Source, Function, Parameter, Mask) > >> 2 = Tools>Analysis>Join Attributes Spatially (target layer, source > >> layer, ...) > >> 3 = Tools>Analysis>Overlay > >> 4 = Tools>Analysis>Spatial Join of Geometries (Layer A, Relation, > >> Parameter, Layer B) > >> 5 = Tools>Analysis>Union > >> 6 = Tools>Analysis>Union by Attribute Value > >> 7 = Tools>Generate>Buffer > >> 8 = Tools>Generate>Convex Hull > >> 9 = Tools>Generate>Convex Hull on Layer > >> 10 = Tools>Generate>Create Thiessen Polygons > >> 11 = Tools>Queries>Simple Query (Layer, Operator, Value) > >> 12 = Tools>Queries>Spatial Query (Source Layer, Relation, Mask Layer, > >> Parameter) > >> > >> > >> > > Hey, seems there is a lot of redundancy :-( > > It will be hard to clean up as many functions are close to each others, > > but not strictly the same. > > May be a solution could be to propose some of them for removal (or to be > > packaged in a special extension) and vote. > > Anyway, you did an excellent job, and I'll try to spend a little more > > time to see the difference between all those function and to tell which > > one are better for me. > > > > Regards > > > > Michael > > > >> Boundary 1 > >> Buffer 1, 7 : first can > >> Centroid of Source 1 > >> Contains 2, 4, 11, 12 > >> Convex Hull 1, 8, 9 > >> Covers 4, 12 > >> Crosses 4, 11, 12 > >> Difference A -- B 1 > >> Difference B -- A 1 > >> Disjoint 4, 12 > >> Envelope 1 > >> Equals 4, 12 > >> Is Covered by 2, 4, 12 > >> Is Disjoint 11 > >> Is Includet in 11 > >> Is Within Distance 4, 11, 12 > >> Interior Point 1 > >> Intersects 1, 2, 3, 4, 11, 12 > >> Line Merge 1 > >> Line Sequence 1 > >> Overlaps 4, 11, 12 > >> Polygonize 1 > >> Reverse Line Direction 1 > >> Simplify D -- P 1 > >> Simplify (preserve topology) 1 > >> Similar 4, 12 > >> Symmetric Difference 1 > >> Thiessen Polygon 10 > >> Touches 4, 11, 12 > >> Union with one Layer 5 > >> Union with two Layers 1 > >> Within 4, 12 > >> > >> > >> > >> Regards, > >> > >> Uwe > >> > >> > >> ------------------------------------------------------------------------- > >> This SF.net email is sponsored by: Splunk Inc. > >> Still grepping through log files to find problems? Stop. > >> Now Search log events and configuration files using AJAX and a browser. > >> Download your FREE copy of Splunk now >> http://get.splunk.com/ > >> _______________________________________________ > >> Jump-pilot-devel mailing list > >> Jump-pilot-devel@lists.sourceforge.net > >> https://lists.sourceforge.net/lists/listinfo/jump-pilot-devel > >> > >> > >> > >> > > > > > > ------------------------------------------------------------------------- > > This SF.net email is sponsored by: Splunk Inc. > > Still grepping through log files to find problems? Stop. > > Now Search log events and configuration files using AJAX and a browser. > > Download your FREE copy of Splunk now >> http://get.splunk.com/ > > _______________________________________________ > > Jump-pilot-devel mailing list > > Jump-pilot-devel@lists.sourceforge.net > > https://lists.sourceforge.net/lists/listinfo/jump-pilot-devel > > > > > > ------------------------------------------------------------------------- > This SF.net email is sponsored by: Splunk Inc. > Still grepping through log files to find problems? Stop. > Now Search log events and configuration files using AJAX and a browser. > Download your FREE copy of Splunk now >> http://get.splunk.com/ > _______________________________________________ > Jump-pilot-devel mailing list > Jump-pilot-devel@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/jump-pilot-devel > ------------------------------------------------------------------------- This SF.net email is sponsored by: Splunk Inc. Still grepping through log files to find problems? Stop. Now Search log events and configuration files using AJAX and a browser. Download your FREE copy of Splunk now >> http://get.splunk.com/ _______________________________________________ Jump-pilot-devel mailing list Jump-pilot-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/jump-pilot-devel
