Logo TIB AV-Portal Logo TIB AV-Portal

Postgis Topology will replace simple feature.

Video in TIB AV-Portal: Postgis Topology will replace simple feature.

Formal Metadata

Postgis Topology will replace simple feature.
Title of Series
Part Number
Number of Parts
CC Attribution 3.0 Germany:
You are free to use, adapt and copy, distribute and transmit the work or content in adapted or unchanged form for any legal purpose as long as the work is attributed to the author in the manner specified by the author or licensor.
Release Date
Production Place

Content Metadata

Subject Area
Postgis Topology is a must if correct and up to date maps are important for you. 1) Normalize data, for instance shared edges should only be represented once. Why : Avoid the possibility for gaps , overlaps, spikes and other error in the result. 2) Must be simple to expand or reduce a polygon surface even if the border line contains thousands of points. Why : Moving many points on a screen is difficult and time consuming and its's often is easier just to draw a new line. 3) Only the actual changes should be written to the database. Why : Or else you may get problems because of projections, different number off decimals in client, protocol and server. 4) Removing lines should cause old surfaces reappear with original borders for layers that has 100% coverage. Why : We want end users update our maps because they know best what is like there, but then we must accept errors and then it should easy to correct these error in a efficient way. 5) Generalize and simplify on the fly. Why : To reduce the amount bytes on wire it's important to give the user a good end user experience. We have now made a simple web client for updating topology layers of type surface, line and points where we are using a simple generic protocol based on JSON.
Keywords The Norwegian Institute of Bioeconomy Research
point degree management Void's directions Normierte Räume arrow distances systems engineering form Gravitationsgesetz
polygons topological meter screens server lines point polygons projects UTM clients Databases Databases Axonometrie degree Folding mathematics degree terms single different archive Cats simulation
point meter polygons topological states time sheaf water shape Axonometrie mathematics degree Formula testing systems area meter mapping formating point projects moment UTM maximal lines bin degree particle Formula Computer animation orders iterations Windows
point polygons topological server time component sheaf clients part versions naturally level testing position exception form tasks user interfaces meter topological binding projects polygons moment lines bin applications particle Location processes case buffer
area topological Computer animation point basis theoretical perspective
point topological Computer animation point lines applications perspective
point topological server implementation lines time forty sets Databases water clients part Coloured computational different structure errors mature area default topological server forces point polygons law Databases completion particle category Computer animation orders input objects sort
point topological server time surface Databases clients lines generic operations arrow extent systems
area point polygons topological server Actions multiple surface time point polygons clients clients attitudes part attributes Computer animation Em's input extent
point pulse topological mapping user interfaces time acidication clients versions geometric different reduce testing errors topological server surface point storage clients bits indicators particle data streaming errors Computer animation chain life reduce record
point standards Meeting/Interview Lecture/Conference time conic infinity
point topological multiple topological user interfaces time forces point polygons plan instance clients several elements Computer animation Lecture/Conference different level Right procedure geometric WAN
choice topological Open Source Software information Meeting/Interview Development extent part systems
point Types topological Meeting/Interview different uniformity level Right geometric elements
topological Meeting/Interview plan Transactional Databases
sheaf lies
topological Meeting/Interview Lecture/Conference classes
Computer animation
but but this is about how to store
Britain In the 1st is that the base it on the depicting borders no common borders and having drifting around this is a picture this shows distinct points in projecting from degrees the red arrows to quite a few of those are placed at a distance after seeing the direction between once a points that are not not just if I that how to solve these problems we look at widest forms have been going when details about these problems but the 1st lady need that ejection like in Norway see the overlaps indeed
there is no way we have used to different projections to get the accuracy of the the so you have to spilled them up into different folds utensils utensil . 2 in 33 and 38 5 databases started painted degrees this is cat affect the data from the Greece to meet their when the users have to see them on the on the screen 1 thing a lot has made it easy to handle polygons across the borders of the term sounds and you can have 1 single archive users prefer to
repeat this so we do the projection from the year from degrees on to meet them this is just a change in the transformed back to Greece and send it back to the database the data that the
test it is that you can solve 33 there this dataset contains order as you know listen In these tests have transferred from little binding to post his there is no protection in all in this very Hall at 68 quality of about 6 thousand points the so let's see what happens project from degrees 2 meters is that point is that the high cost 400 places existed as a simple projection from Greece to the only thing about 6 and window that has not interested the green points are located in the middle of the utensils that's very farmers most accurate there must movement is about 4 mm but very much they talk about maps for all holler so what's the problem of points moving 4 mm there if for some reason is the shape if all play changed before and after that I used to update is impossible because the systematic changes needed 90 per cent all the points so if if a user by system change like the Persepolis system possible to check good place of the sections on these points are extracted from the water was abundant so what happens to the particles and actually uses these borders the after the reprojection 99 per cent of the particles overlap with many of the other particles so before we started yet 0 % now we have 99 per cent of the this is in red areas there you know the less where there's the deciduous lines because our episode tiny like it'll have a formula where this is the formula for women not that this is the new node in this and the red lines and that's because there are some green points there which have been the state of the place but this is all we have but they are not able to calculate and the area because all of is so times the only had lines and points so what happens if it is 100 times that what really much but only the max moment this increase forming that this 2 point for me so and the point that monetization subsisted and that's when the thing what has refused to renew themselves here we see
the borders of overlapping various middle which the data after 100 iterations using the format for North knowledge on the data for it is often the the next together after 100 iterations but the Postal 6 centimeters there actually able to see the calculated and the users who see as a problem for
a popular former former for transporting data from a server to client Jason used in other applications so let's test when the transfer for from adjacent to bind them back the and projections this is really
about it that 99 percentage the points that actually transferred to activities that always so this is just 1 fund-raising to buy a new and better Jason 99 per cent have lost their original positions so if a user for some resources said home and was and this token possible the the told luminance is not repeated it's about 8 nominee that's the biggest moment the total movement is about they're attempting to lead the attending equally there I think that's about that what the half the size of this my hair this is so so that was the problem with this exactly the same form as it had it's there for the at MIT in the 2nd so before and by the end In this section we will do that the judge back again and all the participants there there's also on the problems close by monuments here we have component of the overlap with close to nothing it is not possible to see these 11 and applications that the Board of Trade but this in the future the board in between these 2 particles are oppressed supplies as the nature of simple features the subproblems in the future please all 15 those 2 polygons it's lines and along time the level the problem like W and there's a picture of they see that applications seems to have more problems but having data this way and here's an example of if on an application the last thing is the user that has to be going on there set lectures in 6 to that all border of all those 2 . of and the the of the exception aside location conflict but understand that occasional because the from that have 5 courses the pieces that you get the half of the status of my here I do understand the process and the case of it is possible to decide whether point should be some it is difficult task it is decreased a buffer on the part of the them 1 micrometre there and an application before we did another test and therefore in the to the part of the database it'll make we can make that so the points was the leaders of the 2 political sentiment that also right so just shows that like having the the time no equals a probeset applications and I think what of have seen the topology exceptions so let's the 1st technique we can look at the user interface with simple feature
and here we have an end-user and we want to their increased the theory on the dark side so you get more dopamine area basically what do is to be able to move this line what they get a new line allegedly line and so they're but as
the basis of the basic problem is
feature is that moving that long line take someone the if you could judge each point you can of optimizing still simple to do and what actually what I wanted to draw new lines that this is the fixed the rest so the problem is in the
fisheries at have distinct points are not alone and the other application common 1 the some
talking to solve this problem because of the sort distinct point follows by like using it this but the law that's what the supercoset don't have only single we solve that covers all our it is rounding the role can be done in area that that should have been put forward but is a single the costs to really is not on the you get 0 . 0 3 easy to make errors and actually try to change the input data in a simple way some there novel way to try to solve the problems to get around the problem but some solve the from just walk around it so let's see what what's causing distinct points the problem the main reason for distant points is that the actually send data all to the client and this and that they come back again that's and doesn't happen so if you we don't send the data back from the client to the server the distant point problem is not there so that there the is policy that because there is no simple way by reference using the feature points and put them before so that whole that actually say that only point was changed simple statistical structure if so for is for a point of the kind greatest or part of the sensor to the server is no weighted x simply say that only cheese 1 maturity of 4 points so that's a problem basic problem with simple feature salt the more natural way to do it follows that the drawn in you realize if they want to there later this particles smaller it adopted will lie and say hey these because of the part the capital then the only thing that might impact the server the rest of the data on are the server they don't need so this database takes this line complete computes the new polygons and ask the user what to do with that they were told weighted the distinction problems the there it of course the latest familiar with this but nobody notice of distal formerly with their and it only happened long time the multiple times the but what about the 2nd problem modification wars he said pointed out the border here is actually represented in 6 different objects 1st at the red 21 they are a complete copy of all the points in the border and you see the blue light particles are they also have a copy all the points for you so that all the pieces so all the points in his forties duplicated and implicational data is complicated i is behind this distinction some of course was the default this is these point some of the red color points to the water and the blue polygon points his piece of order and place the same set of data straightforward solution solutions and Sanderson Canada has done this implementation apology the use point that is at accepted that doing this so the
properties that we don't have an existing data back to the service and forces topology and read all different points and underidentification they but so
that we have this system presented to Buddhism from the server to the client this we have at the client all and new lines or points back to the server better to get this to work you have to make extension of posters topology with so that have from some isn't only need to make a package is actually takes a lot of time on the applied to this is the data let them impossible to do without them from some something in the the this is only a there's so this the client that looks like that the
but and other lines the burden and it alone you see the black black arrows there so these disjoint aligned you don't care about what's there before I had visited by new line yes I did a lot people and that line is centered at the so you actually have to use the service but from the database the user decide what to do those 2 surfaces right no nothing happens to database the only thing that happened is that that is created a new surface although all nice like who was making currently all licensees or there no they some of the next operation is this is the doctor this is a way of thinking that send Elijah databases you get it back to the client this helping you if you try altered and also have to be stored in the database that means there's no dissaving you get a totally accurate picture it was the only
user and some new area to existing policy he draws a line that goes starch inside the polymer goes outside and inside the probability of the server computers the surface and it also picks up the some selected attributes from the water column that and activities that have to do something for because by by accident he wanted the same extension on the same attributes there the main to not nice like this from before like last going did not go between those particles from but that's what the important like those can be hidden away or whatever so the input stuff is that he actually change the existing policy of the destroying any and all data and if these actions they had of all that is part of the so there are beginning to move together and everything is back to started isn't that fish that even possible because they had extended the polygon and everything much better
not some notable client examples but I don't have the time to to go through those directly scandal justifies multiplication yeah he's he's found from another research and the idea that history and have given role that of points another thing is to Buddhism so what is the what is there
was adjacent think about urban those a little bit of this and what fixed efficiently to store data the Spitzer indicators is 7 . 6 megabytes the stupid reason 0 0 . 3 megabytes 50 depended 80 % reduction as kind of some it makes sense to use them but this was very interesting future when using tool produces on topology data because it seems that feature simplify it is simplified to particles that are close to each other you get different simplification of the common border so you get a new gaps overlaps than doing simplification with simple features but the topology the line the surface of the only 1 point this means that the common life continues the borders are only is defined once and they always specifically designed to so you don't get any overlaps or get some this example this a wonderful thing difference between those bodies 90 80 % less this also quite important that this like presently because this 1 pieces of that and delivery chain that a do control and that's what kind of alignments from the into the client so it's important to reduce the amount of data going into decline but crime I sitting on the who will normalized by whatever it better capacitance saw that to reduce the size of those data stream portant Saul but this
topology some tend to say that of this topologies slowly so it's possible to import a large amount of data that tested 1 billion points so Christian 1 billion points all the to positive and that took about 24 hours and it also seems to be quite solid background was working you get for lot years ago that more errors in the chicken stock is down you topology practicing acid into the there but I think is positive topologies and gives her matter of these are supported by the around that but it was disappointed you have seen casting from the to see the future this means that it can actually use gets from that the hours before the testing is not very fast but the fastest you have stored like him you have been who then the a major last use that covers suffered scope the reason this version of justice they're on the client's needs to adjacent and DT to render the data that this was the last time the song if you want to avoid the duplication of borders distinct points and those of their own use about it and if you don't care the September like so I'm hoping that the interest in just 4 pulses topology will increase in the future but you never know but then thank OK we have a few minutes for questions so please raise your hand and I'll bring the microphone because otherwise but we don't record questions but if not maybe I have my own question and it's like topology has been around for a a long time also well let's say a well 10 years ago maybe it was not imposed that in well some commercial packages that you have to do do
you have any idea why it is not the like standard already there I get you know that you have done this single points is the you know what the
problem so that I think that's the problem like most of the times of work and but like the and of course it's a conical a
complicated to use force topology and post this triple is not supported by just anatomy so and this needs to be done more examples this topology but and together with 2 were Jason and the tumor and the and the fish efficient clients particularly get up to this thousand isn't it is something that thing people are asking more more about this and I'm not like for instance before the 2nd 2 polygons phrase it touches on other this in the feature that is like the 2nd point in the 2nd set up by the post this topology you do not want he said so you just want to check that to by these shared by 2 other elements because the and the separation of all procedures 2nd to political institutions and that's false the civil rights to see every time so so the come around sometimes hard to stop using them no questions we
have to clearly 0 yes yes I have to run the the the so when the question is began in their body self municipalities so when you want to use a typology for different levels of municipalities and then you would need some efficient way not to to duplicate geometry in multiple level see is there any plans to
account for that gene topology do you think it's possible then thing rephrase the question was not sure if I totally cached so as you you are using this said both this topology and I suppose you you are a part of the development of an iconic and this and that and the use of open-source software we have added you're very useful system wanted package and about half of this information to make some extensions to OK so and then all of them in
for this year but I'm not developed much impostor supposed to say that some of the those choices did catch that your question correct so did they the
question who was there how do you think the topology could be both this typology could be extended to account for different uh different levels of geometry uniform municipalities and there is a high 100 people there in different type
of lute higher right that he that he can levels in the post this topology so we can make the begun municipality and you can have a country that depends on that thing so there is this hierarchical elements in their and use that the itself but there as far greater disadvantages lower way the deduplication of Points and borders a lot of Ontogrator tips OK well I think we have to
finish this session so you can then move to the next 1 well maybe I can still there was no question that I can still take a but the next speaker can perhaps already and in some and I have 1 question about 50 think is of topology do you know about the plans for example that the for example the Web Feature Service transactional with support editing of the
topological or do you know for example there is applied into QTC where you can connect to post this database to the topology and headed topology in acutely yes and I had this abundantly is so there's a beginning use and
I will use that early so all of them better that they got everything in they're not all the implementation in positive so it's 100 per cent interest transactional so so data don't lie for precision impossible I does this work and it's done by
the user see that we don't succeed so it's a section the
the plug-in in Judas it's not like the issue is more like there is black and the reckon that must have some the a lot of class for a few years later on topology but there yeah yeah like