I need to design a web app that allows visitors to draw and label basic shapes. The visitors will be drawing a basic map of a store. The shapes drawn will need to be stored in a database (their coordinates and sizes) along with their labels and a few options so they can be easily replicated later in a different app.
What's the easiest way to accomplish this on a web page?!
If I was doing this, I'd use Raphaël.
Check out the demos on the above link, it can do all sorts of crazy.
If you're after an actual code sample, I'll have a go using Raphaël if you like.
It works in many browsers:
Raphaël currently supports Firefox 3.0+, Safari 3.0+, Chrome 5.0+, Opera 9.5+ and Internet Explorer 6.0+.
Take a look at http://zwibbler.com
You can draw some cool shapes using pure CSS.
Check working example at http://jsfiddle.net/yFn6z/1/
Also more way to draw CSS shapes with borders http://www.vanseodesign.com/css/creating-shapes-with-css-borders/http://www.sendesignz.com/index.php/css/68-how-to-draw-speech-bubble-and-shapes-with-css3http://net.tutsplus.com/articles/news/fun-with-css-shapes/
If you want to draw vector shapes of all kinds use Raphaël javascript library.
If its lines and circles, You can use Bresenham's algorithm (Read up more in google, a 1x1px div with the color of your choice represents each point of a line or circle) once the algorithm has been implemented, you can use setAttribute to assign whatever attributes you want to to each line or circle that the user draws and store all the data by separating each shape with some proper delimiters and store it as a text file using FSO. The stored text file can be used as a means to save the users progress.. etc.
Related
I am building a web application in which the user would be able to draw zones (polygons) onto a video. A solution I already implemented was to put a <div> on top of the video player, catching the mouse clicks.
What I'm willing to do right now, is being able to draw on that <div> with the mouse:
Click on the block to draw a point
A button, Draw zone, which would fill a polygon with the existing points
A button, Delete canvas, which would reset the block
I am looking for directions about which library to use. Already heard about:
Raphael (raphaeljs.com/#demo)
jsDraw2D (jsdraw2d.jsfiction.com/demo/linepolygon.htm)
Problem
Raphael looks monstruous but kinda overkill for what I want to do. And on the contrary, jsDraw2D seems to work just fine from what I tested (only drawed manually though).
I have several constraints such as:
The user is drawing the points with the mouse (by clicking)
The user is drawing on a <div> with opacity on (the filled polygon should be transparent too)
I need to store the points' coordinates (or of the polygon at least)
Question
What should I use ? Should I stick to Raphael even though it's a bit difficult to implement (I've basically no background in JavaScript) ? Or do you know of a JavaScript library which could do what jsDraw2D does but in better ?
Thanks,
You should use SVG because they are obviously more interactive and easy to implement. If you've ever used Khanacademy then probably you'll come to know that they use SVG in their scratchpad.
Moreover, SVGs are also w3c recommended like canvas.
If you are able to go for HTML5 Canvas could be a good choice.
I'm working on displaying interactive map in html5.
I have created zones of map as array of numbers (representing coordinates)
like:
Zone1=[{x=3,y=4}, {x=8,y=5}]
and I have also created a map which is an array of zones
like:
map=[zone1, zone2....]
I have no problem drawing the zones in the canvas using context.lineTo() function, the same way I'm able to capture the mouse position on click and determine on which zone a user has clicked using point in polygon algorithm.
My difficulty arises when I want to fill color of of the zone when it is clicked at.
Anybody have ideas?
PS:
The shapes I made are irregular
I'm not in to using JavaScript libraries like jQuery or anything else
HTML5 Canvas does not know of notion of shapes of objects which you can manipulate. You have two options in your situation:
Use SVG to draw what you need (check examples on W3Schools)
Use some JS canvas library which adds abstraction to provide notion of shapes (check out EasleJS)
Write your own abstraction over canvas to provide shapes
You should know however, that even with such libraries, "shapes" are getting fully redrawn. Possibly, entire scenes are redrawn. SVG alleviates this, it's performance decreases as number of shapes/objects grows.
You can't. The shapes you created are not variables or referenceable in any way once they are added to the canvas. You could redraw the shape with a new colour over the old one, but I think your best bet would be to use a library to handle this for you.
Since I have used it myself, my own suggestion would be Kinetic.js, but there are a plenty to chose from.
I saw a picture mapped to a cylinder in CSS3 and I was wondering if this is possible with a text. Even better would be to map the text to a sphere. If it is not possible with pure CSS, Javascript could be an option.
It must run on all major browsers, also those not having the -webkit- stuff.
Thanks in advance.
As mentioned in the comments CSS3 only supports rotating and skewing elements, and doesn't have any support for spheres.
Although you can fake a sphere in SVG using something like Raphael.js, i don't think there's any real support for doing 3D stuff using Vector graphics. You'd have to map/wrap/skew the text yourself using some crazy math, and it still might not even be possible.
I think your only real hope is to use something like three.js to create an actual cube object. Then you could write your text to a hidden canvas element to get an image of the text, and map the image onto the cube as a material, as in this example.
I am currently trying to create a blue, circular, pie-chart-esque image for my website. The circle will be split into 6 different segments.
What I want to happen is that when the user hovers over a particular segment, this segment will turn orange, and some text will appear beside the circle corresponding to that segment.
I have found some resources online which achieve nearly the effect I need using CSS image maps. http://www.noobcube.com/tutorials/html-css/css-image-maps-a-beginners-guide-/ However, these techniques split up an image using rectangles. If I were splitting up a circular object I would prefer to split up the area based on particular arcs.
I assume this is beyond the reach of pure HTML and CSS. I do not have a great deal of experience with web languages, although I have had passing experience with JQuery. What are the techniques I need to solve my problem and what technology would be best to implement it?
you can create image maps that are not rectangular, but use polygon shapes.
this useful tool http://www.image-maps.com/ will let you achieve what you are looking for, without having to write your own polygon mapping!
A few options:
HTML image map
It's simple to create an HTML image map that comes very close to the shape of each slice of the circle, but there are limitations to HTML images maps. For instance, you can't nest content inside each slice of the image map (as an easy way to implement a hover pop-up). If an HTML image map is adequate for you, it's the simplest solution.
CSS image map
To define circle-slice shapes, a CSS image map is impractical, unless you only need a very-rough approximation of the hotspots for each circle slice. But if you could live with that, you'd have a lot more flexibility as far as the functionality.
onmousemove
You could also get the mouse coordinates with an onmousemove event handler for the entire circle, and then do your own calculations to determine which circle slice the mouse is in. This allows you to accurately define the hotspots for each circle slice, and you'd have more flexibility than with an HTML image map. But the calculations may take a little work.
I have a solution for this using mainly HTML and CSS with a tiny bit of jQuery to handle the showing of the text by the side of the circle.
It does however use some CSS properties that are not very widely supported such as pointer-events
JSFiddle Demo
I've an application that based on some values from different inputs (temperature, humidity...), show different charts.So far I've done that with JpGraph, and I found it pretty easy to do. You can add a legend easily, and plot as many functions as you want. You can also fix the scale easily. Regardless of that, I would like to have some interactivity with the user (I just want that one the user clicks on a point of the graph, the X and Y value are shown). That is not easy to do with JpGraph because it is just a PNG image.
I was recommended to use Raphael JS library, and I've been reading to the documentation (Raphael JS Reference), but I don't see that what I want to do (line charts) is that simple.
So, I am asking, to both Jpgraph users and Raphael JS users if they had had experience with this, and if there is any good tutorial online (I have not able to find one that works with line charts). The kind of graphs I'm drawing now are like this: JpGraph Example
Some other options:
D3.js (SVG)
JSXGraph (SVG and VML for IE)
Protovis (SVG)
There is a chart plugin for Raphael. It supports line charts. The documentation is certainly lacking - but there is always the source.
Answering myself. After doing some research, I found this one pretty interesting for doing line charts:Grafico