I'm new to html5 and am having a problem with drawing custom markers. I tried using the code from this tutorial. I'm trying to use circles instead of rounded rectangles but my circles are getting cut off on the right side. Here is a screenshot. I tried replacing the rectangle drawing code with
context.arc(radius,radius,radius,0,2*Math.PI, true);
Can anyone tell me what I am doing wrong?
never mind I was setting the canvas height and width incorrectly.
Related
I implemented script from hereHow to make a tkinter canvas polygon transparent? to my program.If I use breakpoint at function from sample, polgon is filled. Polygon is empty when I do not use breakpoint. I have to note, that my drawing is more complicated than sample. If I use only sample all is OK. Do somebody able help me with canvas refreshing?
I need to select an rectangular area on a map and identify markers that fall within that area.
Ideally, rectangle should be draggable and resizeable.
I am not too particular about the mapping and Google or Mapbox or Leaflet would all work just fine.
I found location-filter for Leaflet (https://github.com/kajic/leaflet-locationfilter/), which does seem to do the job. However, I couldn't find simple example code that shows how to use it. It has been used on tripcode.com but it is hard to make anything out of what is going on.
Does anyone have any experience with location-filter? If so, can you please point me to simple example of how to use it?
Are there similar examples for other mapping services particularly google maps?
Thanks.
For my bbox page I've snatched two files: SimpleShape, Rectangle from Leaflet.draw plugin and fixed them for better usability. The code for the rectangle is simple:
var rect = L.rectangle([[59.9, 29.9], [60.1, 30.1]]);
map.addLayer(rect);
rect.editing.enable();
rect.on('edit', function() { console.log(rect.getBounds().getBBoxString()); });
For advanced things like centering the rectangle on screen, see source code for the page.
When you are drawing the markers onto the map you will need to add them to some kind of an array which will contain the lat/lng pair of each marker.
You can use Leaflet.draw to draw the rectangle and modify it to return top left and bottom right coordinates on mouse up. On mouse up you can go over the entire list and which elements fit inside that bounding box.
This solution is just an example, there are many ways you can do this.
I have a google map as page background and a few div layers above it. When I place markers on the map I would like to be placed in the visible part of the map, not below the divs. In other words.. I need to add padding to the map so the functions like fitBounds(), setCenter() and etc. to position the markers in the visible part of the map.
There are many examples around but none of them looks quite well or it is working at all. Most of them are similar to:
I have tried to calculate the bounds and to extend bounds with some padding but it is a two step process. At first.. the map is positioned at original bounds to get the correct projection and then it is animated to the extended bounds. It doesnt look professional, we have two fitBounds() and the second one is animated. http://jsfiddle.net/seddass/CuKTK/
I have tried to add custom control to my map but it seems that the custom controls doesnt add padding to the map as suggested on many places. http://jsfiddle.net/seddass/wtT3t/1/
Can anyone can provide a working example or a better solution for padding to for Google Map v3? Thanks in advance!
I'd like to replicate the outline effect shown on this map: https://maps.google.co.uk/maps?hl=en&safe=off&q=switzerland&ie=UTF-8&hq=&hnear=0x478c64ef6f596d61:0x5c56b5110fcb7b15,Switzerland&gl=uk&ei=PXO3UK3UPMS1hAfmjoDgBQ&sqi=2&ved=0CKQBELYD
In other words, I'd like to draw a path that:
is shown along one side only of the path defined in GeoJSON
fades in transparency from the outer side of the path to the inner?
Are either of these things possible with the Google Maps API?
I believe to do this you would need to create a custom overlay - which can be a somewhat daunting task. See the documentation on Custom Overlays for a basic example.
Were I implementing this, I would create an overlay which used HTML5 canvas elements as tiles.
I'm having difficulty drawing lines on top of an uploaded "map.gif" image.
Basically I've upload a small outline map and use the "area" function to create defined areas (cities, roads, etc). When I click on a city a snall pop up gets displayed with the word "hey, you've just click on Dallas" (or where ever). All that works just fine.
My problem is that my map is actually just a blank outline with no actual cities or roads drawn on it.
Therefore I tried using the "canvas" function to draw the cities (circles) and roads (lines).
The only problem is that they appear below the map rather than on top of it.
Any ideas as to how I can get the lines to appear on the map?
Many thanks,
Pete
You might just have to try playing with the CSS z-index values of the image and canvas.
Do make sure you set the canvas to be transparent.
An other possibility is to replace the image with the canvas (or just load the image in the canvas to begin with).
For some hints on how to use images with canvas take a look here.
I would load the gif directly in the canvas memory, and then do all the rest inside the canvas itself.
The gif is not animated, right?
Some reference about loading: https://developer.mozilla.org/en/Canvas_tutorial/Using_images