CloudCompare Tutorial 01 - Opening files and basic navigation

all right everyone so welcome back we're gonna take a look at cloud compare today so this will be our first look at cloud compare as a point cloud manipulation software and today we'll be looking at getting data in some of the options to get it in and some basic navigation around the program so whether you're on Windows or Mac you can open up cloud compare so right now we're using version 2.10 point two on Windows but the interface should be the same on all platforms so I have mine set up a little bit differently probably than the default I don't honestly remember what the default settings were but I know I've changed my toolbars around so if you see a toolbar or me going for a toolbar that isn't in the same place on your machine that's totally okay you're welcome to move those toolbars to wherever you like on your screen all of the toolbars are dockable so the first thing to kind of get familiar with is the basic layout of the screen so on the main window here is the 3d view so this is where our point clouds will show up up on the top left here is what's called the DB tree your database tree and so that is going to be all of our different layers and folders and we can rearrange things in there as we see fit the properties window down here once we have a point cloud loaded will actually show us some of the display properties of the point clouds and let us change which attributes are displayed and do a lot of fun things in there so we'll get to that probably in the next video the bottom here is the output console and this is actually probably for beginner users probably the least useful thing in the whole program so if you want to go ahead and X out of that so over in the corner of the console bar here you can actually click the X and get rid of that window so that you have more space on your screen so in order to get a point cloud in it's simply going to the open menu up here so I can show you that that icon up here so just up in the upper right hand corner here the Open File dialog pops up and so in here you can navigate to the point clouds that you want to use or want to find and so cloud compare will take in just about any file type that has some kind of 3d data associated with it so just here in the file browser you can see that some of them the more common ones are ASCII clouds so CSV files or XYZ files or points files so those are basically just text files with 3d data in it the other most common that you'll probably use a lot in cloud compare are lis or last files so those are light our files and cloud compare can but read both the lis and they'll AZ the compressed versions other ones that you can read in here are PL y meshes obj meshes STL's for 3d printing DXF geometry from cad and then cloud compare also has a lot of you can read in images and even shape files from GIS as well so we won't get into too many of those in this series but the primary ones that we'll be using are ascii point clouds and lis clouds the one more important one is right at the top of that file list is the the cloud compare entity is a dot bin the file and so these are if you save a cloud compare kind of document if you want to think about it like that with all the different point cloud entities in it those will save as a bin file so you can actually open up a whole series of point clouds as a kind of stored bin file now will warn you that those can get rather large if you have multiple big point clouds in there so be careful when you're saving out point clouds so in order to get a point cloud in all you have to do is find the point cloud that you're interested in and so for this demonstration I'm just going to use a point cloud that I used for some research of a river and so in this case this is a CSV file so I'm going to click on that and open ok and since this is a CSV file we get prompted with a kind of another dialog asking us to kind of identify the different columns in our CSV file so in this case you can see that my CSV file here has a header row so I have an X column a Y column and a Z column and then a bunch of different attribute columns out the side here so in order to get this to read incorrectly oftentimes you have to tell it which columns belong to which values so in this case it's it usually tries to guess and it does a pretty good job at guessing which is the x coordinates which is the y coordinates and which is the z coordinates for the points but if you need to change those for any reason like let's say you've got YX is e if you click on the drop down menus here at the top you can actually change the different field types so whether you want to change this to the y coordinates or the x coordinates of the z coordinates or there's other types down here too so if have red green blue values for point cloud colors you can do that down here or another kind of popular one for a lot of attribute data is just what's called a scalar value so let's way down here at the bottom so in this case it's guessed that it's as a comma-separated file so down here in the bottom you can see that it's got a comma in the separator field and then the next-to-last option down here at the bottom is skip lines and so in this case we have a header row so we actually want to skip that first line because it's not valid data and so if we hit the up arrow on that you can see that that gets rid of that first line and then another interesting thing that pops up there pops to be available is this extract scalar field names from the first line so if you have attributes out in your point cloud it can actually extract the names of those from that first line automatically so that's pretty slick so we'll go ahead and hit apply on this one and then for most geospatial data you actually will get this it's called the global shift and scale dialog to pop up and basically cloud compare tries to keep things simple in terms of coordinates and so for large geospatial coordinate so those associated with like UTM or state plane or the or other kind of gridded coordinate systems that have very very large coordinate values cloud compare will actually do what's called this global shift and scale to actually kind of subtract out a constant from each of the different XY and z values in order to get the point cloud to display properly and not take up too much memory so this is usually a good thing to do I wouldn't suggest skipping it because if you do as you can see it's the the warning at the top of the screen here is that the coordinates are too big and original precision may be lost so if you're using giant coordinates so in this case this is on the British National Grid and so our x coordinates are in the range of three hundred and thirty-eight thousand and our Y coordinates are two hundred and seventy two thousand and so what Klug compare will do is subtract out those constants so that we're left with coordinates that are a little bit more manageable in the kind of twenty nine and eighteen range rather than three hundred thousand range so plug compare does a pretty good job at suggesting a constant to remove from this and we'll look at importing another file and applying that same offset to it as well and so it's pretty smart in its ability to do this so usually I just go with the suggested unless you're looking for a very specific offset here so you say yes that will apply that shift in scale and then it will import that clout that point cloud' so depending on your machine this can take a matter of seconds or for larger point clouds maybe a minute or so but it usually loads fairly quickly and so what will pop up is kind of a default view of the point cloud so here you can see this is our River so in this case a river is flowing from the left side down to the right side and if we click on the the point cloud over here in our database tree you can see that our properties window now gets populated with a bunch of different stuff and so if we just go down the list here the first thing is visible or not and so that's the same as the checkbox up here in the DB trees so if you uncheck that that will turn on and off the point cloud or if you have multiple entities kind of nested over here you can actually turn them off individually with that visible tab the next important one here is the colors so if your point cloud has both scalar field attributes and RGB data this is where you can switch between the two and so mine has RGB data so I can switch it to RGB colors and so here if we zoom in you can start to see the colors of our river so you can see some of the sediment here on the banks but then the ins in channel portions are this kind of brown green color so if we switch back to our scalar fields in this case if we'll go down to the bottom and look at which scalar field is active and that's the current one that's going to be displayed with that scalar field so some other interesting things that you'll find in here are some information about the point cloud itself so what it's what the number of points are in the point cloud so this is 1.9 million points you can also change the size of the individual points so if i zoom in here you can start to see that we get start to see individual points but if we change the point size here that actually changes the size of the points in our display so usually I just leave these at default I'll show you another way to change those in a minute globally across all the data sets but usually just leave point size at default and then lower down in our properties window here is our our scalar field and so here you can see that this date this point cloud has 10 different attribute fields and this is just as an example your point cloud can have anywhere from 0 up to as many as you want to add on but for the different scalar fields you can use this drop-down menu to pick the scalar field that you want to display and so if you want to look at if you're looking at a lidar file you might have scalar fields in here of like intensity and return number and classification this is some derived data from a bathymetric correction so I've got kind of random ones in here so things like water surface elevations and the original point cloud elevations versus the corrected bathymetric depths so you can choose which point cloud you or which scalar field you want to display in this menu drop down menu here so in this case we're just going to look at the original Z values for the point cloud and then the color scale you can choose a custom color ramp to display the colors so this will display from low to high based on the values in the in the the scalar field and so you can change these to be whatever you like there's an editor in here as well so you can actually create custom color ramps if you like as well we won't be going over that today but you can change these colorants to be whatever you like the default is this blue green yellow red which is pretty good for most things and then down here at the bottom of the screen you can actually see the display parameters for that scalar field and so this is kind of a histogram of the different values in that specific scalar field and we'll look at that and a little bit more depth in terms of displaying specific attributes in a later video so in terms of basic navigation of the point cloud you can use your mouse wheel or if you've got a touchpad you can use your kind of finger scrolling to zoom in and out so I'm just using my mouse wheel here to zoom in and out and then the other two basic kind of maneuvers in this 3d point cloud space are if you left-click you'll rotate the point cloud and so this is a kind of true three-dimensional rotation so you can click and drag and rotate the point cloud around its center point we'll look at how to kind of change that center point in just a it but so that basic left click and drag will rotate around and then if you you can zoom in and out based on wherever you are kind of rotated around as well so you can zoom in and out and rotate just the same so the next basic command is a right click which is a pan move so if you right click and drag you can pan left and right or up and down on the screen and so zooming way out again you can just you can move that point cloud kind of around and up in a panning fashion so there are some default views as well for the 3d view that you'll find on your toolbar mine is over here on the left hand side but these kind of orange squares are some of the default views and so if you hover over these you can see what they are so the first one here is a top view so if you click on that that'll be a top-down view of the point cloud the front view is in this case for most landscape and geospatial data is a kind of a side profile view from the front another profile view from the left-hand side the back the right-hand side and lastly is you can look at a bottom view from underneath now for geospatial data that's not particularly useful but for other 3d modeling tasks that might be useful the last two down here are a front and back isometric view so this is kind of a tilted view that's really useful in in 3d CAD and 3d other 3d kind of design software's is this isometric view so kind of a tilted angled view so usually if I get totally screwed up in where I'm at or if I'm zoomed in way too far and get kind of out of whack oftentimes the best bet is just to go over here and set top view to get the the top-down view which is what we're used to as geographers and geospatial scientists so that's kind of the the basics of some of the view the viewport stuff if you do get completely lost let's say you get turned around and your point cloud is completely off the screen if you click on one of your point clouds that you want to look at you can actually hit the magnifying glass over here and it'll zoom and Center two selected entities so that'll bring you back to kind of a default the default view that you started with so one other kind of navigation thing that you can manipulate is the center of rotation and so over here on the left hand side up on my toolbar here you'll see that there's two little crosshairs I can show you those over here so there's one that says Auto and one that's just blank and so the auto one I think is the is checked by default I actually usually turn that off just because it can screw up in certain situations so I usually turn the auto off and then the other one that the top kind of blank one is what's called the pic the center of rotation or pic rotation center and so if you click on that then you can click on anywhere in your point cloud and kind of establish the new center of rotation and so with that tool active you can see down here in the bottom it says pick a point to be used as the rotation Center click on the icon again to cancel so if you click on this again up here is the pic rotation icon it'll cancel that but if you want to actually pick a new rotation Center you click on the point cloud where you want to rotate around and oftentimes this will pop up the first time you do it this is kind of generating what are called the octrees to accelerate the point picking process I usually always do YES on that it saves time and makes things quicker and so now you can see that we've picked a new point as the rotation center and so now if I click and drag with my left mouse button I'm now rotating around that point we just clicked and not the old center of the the point cloud over there so this is useful if you're working in a very specific area and you need to just rotate especially when you're way zoomed in like this you can pick a new rotation Center and rotate around kind of the this spot that you're working rather than rotating around the center of the whole point cloud which can get pretty obnoxious in a certain sense so those are the basics of navigation around the point cloud it takes some getting used to to kind of get you get your kind of sea legs if you like trying to get like trying to find the right view and zoom in and pan and rotate to to look at the things and look at the features that you want to look at but it just takes a little bit of practice to get that going so if you do want to remove a point cloud from your view here you can do that in two ways one is to right-click on the point cloud itself and say delete so if you do that it'll just remove the point cloud from your view it won't actually prompt you for that you are deleting it it will just delete it that's assuming that your knowing and it's assuming that you know what you're doing I'm going to load that back in just with the defaults okay so we've got that back in so the other way to delete the point cloud is with the big red X up on your toolbar at the top so zooming in on that you can see this the big red X up here is the same as delete so whatever point cloud you have selected in your DB tree if you had X up here it will delete it from the from the window so you can add in of course multiple point clouds I guess the assumption is that you're going to be doing this in the same coordinate system in the same area so if you have point clouds that you want to add in altogether you can add these in as separate files so here I'm going to pick a last file to show you what the import for the last file looks like so we're gonna open this and so instead of getting the the ASCII import with all the different columns since last files are a pretty established file standard there's just a kind of set set set of attributes that you can import so in this case again usually I just leave this as default for most things so if you say apply it'll bring up this global shift and scale again and so the key thing here is that the top option right here is last input so Cloud compare remembers what the offset was for the last thing that you imported and so it'll apply that same offset to the next thing that you import so if your point clouds get off kilter you might want to double check this but again generally if you're importing from the same coordinate system the same offset will put it in the exact right place so you don't have to usually worry about changing these too often so if we say yes on this right import this one and this is about 8 million points so here we've got that second point cloud imported now and so here in this case of our River this is just this is the riverbanks as opposed to the channel point cloud that we imported before so now you can see over here in our database tree view we've got those two point clouds so the the channel right here so on and off and then the banks here on and off so zooming in and rotating again you can start to see that this is a pretty nice high resolution point cloud of our River but with both of those turned on okay again you can turn these on and off separately if you want ok so just look at the river or to just look at the banks or in a combined view and so that's how you can get in two or more point clouds in the same coordinate system into the same space in your 3d view so the one thing you do want to be careful of on kind of slower computers is having too many points loaded in here can get a little taxing for your computer since it's drawing a lot of information all at once cloud compare will it's called decimate on move so when you actually move the point cloud with a lot of points in the screen you'll actually see the point cloud kind of go a little fuzzy until you stop and then it'll rerender all of the points in full resolution so don't be don't be scared if as you kind of pan around or zoom in and out sometimes you'll see the point cloud get a little fuzzy and then come back to full resolution once you stop moving around so the other thing that I want to show you here before we kind of call it quits for this specific lesson is changing the the global point size and so in the properties menu over here we can change the point size for individual point clouds but if there are times when you want to actually increase the point size for the entire view all at once if you just take your mouse and kind of hover in the upper left up here you'll see that this little gray box kind of pops into life and so it says default point size and default line width and since we don't have any line features in here that's not really a useful feature for us right now but if you click on the plus and minus here you can actually increase the point cloud size the default point size to to change this for all of the point clouds all at once so if we zoom way way in here and hover over that upper left corner okay we can decrease the point size and increase the point size as we need to up to I think a value of 15 Oh it'll go higher 16 16 is our maximum point size and so you do want to be careful of this because if you make points up cloud size point size of 16 sometimes it'll start looking like a bit like an impressionist painting so definitely don't go that big unless you absolutely have to but sometimes when you're zoomed way way in on a data set it can look a little weird and so by increasing the global point size just a little bit you can start to see things just a little bit better so that's the basics of getting some data into cloud compare and kind of getting some navigation done around the scene so I would recommend that you definitely kind of load in some point cloud data and try out all of those things kind of in the order we talked about just to get a feel for how to navigate around the scene and how to reset the scene just in case you do get lost because you will get lost I get lost all the time when I'm kind of rotated in and zooming around I'll lose my point clouds every so often so knowing how and how and when to get those standard views to kind of work in your favor it's usually a good thing so we'll call it good for today and I'll be back in the next video with some more kind of advanced editing features and we'll in future videos we'll start to look at some of the more advanced analysis techniques as well

Channel: James Dietrich

Views: 13,778

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Id: IitUKpvBVBg

Length: 28min 42sec (1722 seconds)

Published: Wed Apr 01 2020