I am looking for a good java library to manipulate box, arrows and labels in order to dynamically create and fill diagrams like the following and render them to a png :
Another example
I can create a static template to be filled later, but I will need to dynamically create labels for every box and edges in the diagrams.
For now I have tried using batik to manipulate an svg template but creating multiline labels for the edges is proving quite complicated. The SVG way with batik seems to force me to create 1 text object for each label line with absolute positioning for each which is a real pain.
I would like to be able to define the label specifying only the text and the link they relate to, eventually some hints as to how it should be placed and let the library place them.
Any suggestions ?
If this is in a commercial scenario, the Java graph drawing library yFiles can be a good match for your requirements:
You can use a convenient API to create and style your diagram and automatically layout the diagram with lots and lots options to constrain the resulting layout to suit your needs.
Multi-line and (simple) HTML labels are supported out-of-the-box.
Also you can export to PNG (as well as other pixel based image formats) and vector graphics formats like SVG, PDF, EPS.
This can be done both in a regular Java (Swing) application as well as in a headless environment (e.g. to create images on a server and to send them to a web-based thin client dynamically).
To get a feel what can be done using that library, I suggest you take a look at the freely available graph editor application "yEd" that is based on yFiles and lets you try out the above steps in an interactive manner.
(Disclosure: I work for yWorks, but on Stackoverflow I do not represent my employer.)
Related
I implemented a PDF Viewing widget in C++ using Qt, loosely based on https://doc.qt.io/qt-5/qtpdf-pdfviewer-example.html, using the pdfwidgets module. (For this question, we can assume that I copied the code in that link 1:1).
This works well so far.
But now the thing is, the PDF I want to display happens to be an animated PDF. Opened in a regular viewer like Acrobat, it will show a short sequence. That sequence is located on a single page, the frames are not different slides.
In the documentation of the QPdfDocument and the QPdfPageNavigation classes, I can't find any functionality that deals with animated pages. It would suffice if I had any way to set the current animation phase.
Is this possible at all? If so, how?
It's not implemented at the moment. On Windows, you could use an ActiveQt widget to embed Acrobat Reader inside your application, if present. Otherwise you'd need to find a PDF rendering library - most likely a commercial one - that has such support.
My ultimate goal is to have map data (offline, because I will customize it myself) and display it in an app (Android). I could make osmdroid work to load maps online and I was trying to figure out how to download and display offline maps. I downloaded MOBAC (Mobile Atlas Creator) and export the data to SQLite format and when I had a look at it I realized that tiles are saved in image format (PNG).
What I would like to do is to import data to the phone to later use it in algorithms such as a search engine or a routing algorithm, so I need the "nodes" and "ways" (as I get them from the original OSM XML), import them to the phone and visualize it to later have this data available for the algorithms I want to develop. Basically, what MAPS.ME does. I think it wouldn't be difficult to convert the XML into the SQLite since a simple script could make it, but then, how can I generate the tiles from this custom SQLite database? Or, is there a way I can download the data in a more appropriate way to do what I'm planning to do?
Thanks.
Rendering the tiles in an app from raw Openstreetmap data would be computation heavy and inefficient. I would suggest to use image tiles you exported for visual representation.
In addition to tiles you should export a data set you will need in the application for desired functionality. You will not need all data from Openstreetmap so you should identify what you need and build your custom export (there are tools and libraries for processing and filtering of Openstreetmap data. I have used pyosmium for some filtering and processing but there are others.) For example, you can build your custom database with POIs you want to search for.
Routing is another chapter. You can implement it yourself but it is a very complex task. There is java library called Graphopper which can do the data extraction (from Openstreetmap) and offline routing for you. They have an online API too but it is possible to make it working completely offline (I did it for one application). Try to look at the source code because than you can see how complex topic routing is. Final note: data exported from Graphopper contains information about some POIs along routes. It may be possible to search for some things via its java API but I haven't investigated this yet.
What I have in mind is that user will select the part of world he/she wants to generate roads and retrieve openStreetMap data and use it to render roads in openGL.
On searching the web and experimenting, I thought of this approach:
get xml file of selected map
parse the xml and generate roads by openGL.
But I think this is very naive approach.
Also to experiment a bit I used OSM2WorldViewer to convert the xml file to obj file and imported that as a model in openGL, but this method is cumbersome and takes time
and I am unfamiliar with OpenStreetMap api and how it can be used in such a project.
Any suggestions, or helpful links how to start this project ?
EDIT: How it ended: Link to the project wiki
Why do you think your approach is naive? Either you have the user to provide a self-downloaded XML file or you have to use an API to retrieve one yourself. The latter approach allows you to implement an automatic update mechanism whenever the user pans the map.
Instead of the main API you can use the Overpass API for downloading data. It's faster and more flexible to use, allowing to specify which element types to download (e.g. only roads and buildings) and much more.
You already mentioned OSM2World, take a look at its freely available code to see an example implementation of a 3D OpenGL renderer. Or take a look at one of the other 3D renderers for OSM.
How can I, programmatically, draw a KML-file (routing information on a map) onto a map and then save the result to a .png-file?
What I try to accomplish: a program of mine (written in C++) produces a route. Now I would like this program to emit a .png-file instead with the route draw on it.
I've looked into the google maps api as well as others (e.g. cartagen) but google maps is java-script oriented and cartagen produces html5 output.
Probably you can use Qt Framework to achive this.
It has great XML support so it should be easy to read KML.
It has support for drawing simple shapes.
It has support for PNGs too.
There is also library called libkml - it can probably help you with manipulating with KML files.
I highly doubt if there is any "Ready to Use" solution.
I want to create levels in my cocos2d game and I do not know how to do that with .plist files ... I searched the Internet but unfortunately I couldn't find significant information on how to implement these property lists. Can you please help out ?
Check out Tiled Map Editor. Tiled's TMX format is supported by Cocos2D.
As with any Apple technologies, the first place you should start searching for is the developer.apple.com website. In this case, here's the Property List (plist) Programming Guide.
However, I find property lists very awkward to work with, specifically if you want to create them manually and whenever they contain more than just a few entries. It certainly can't hurt to evaluate rolling out your own file format, text-based plain and simple. I would always rather work with simple text files like these rather than messing with property lists:
X=10;Y=10;Tile=30;
X=12;Y=11;Tile=28;
X=16;Y=19;Tile=22;
It's a different story if you actually design the data with a tool or within an app, where you'll be able to make use of the various collection convenience methods that save and load property lists, for example to and from a dictionary or array.