I have a png image of other map that I know the original bounding box and the original projection. This image is 400x400 large but I have control over its width and height and can generate any size I want.
How can I position this image over my OL map in the correct location?
Both have same SRID.
Sorry guys. I need to learn to search a little more before ask.
var imageLayer = new ol.layer.Image({
source: new ol.source.ImageStatic({
url: 'http://localhost:8080/mclm/img/export.png',
projection: 'EPSG:4326',
imageExtent: [-44,-23,-42,-21]
})
});
Related
I construct three polygons in the google map using the help polygons in google Map API for developers site. They are look like one polygon inside an another polygon .When my page is loaded all three polygon are loaded.How can i get the inner polygon when the outer polygon is zoomed or clicked in google map?Image:polygon inside another polygon
Your polygon are just place in postion that appear as one is inside another
for google maps the way you place your polygon had not a topological meaning
A easy eay for avoid that a larger polygon is over a small one could be based on z-index
assignin z-index with higher value to the polygon over the others eg:
// the larger - at base
var polylgon1 = new google.maps.Polygon({
...
zIndex: 100
});
// the middle - at medium leve
var polylgon2 = new google.maps.Polygon({
...
zIndex: 200
});
// the smaller - at top leve
var polylgon3= new google.maps.Polygon({
...
zIndex: 300
});
I have a feature with an Image, it shows well on the map.
var style = new ol.style.Style({
image: new ol.style.Icon(/** #type {olx.style.IconOptions} */ ({
src: imagesource,
})),
});
But when I add a select control on the layer
var selectcontrol = new ol.interaction.Select({
});
Only part of the image is clickable if the image is larger. Is there any settings to set here so that the whole image is clickable.
Here is a fiddle for the issue, you can see the cursor changes as you move to the center of the image, but the feature is not detected at the corners of the image
http://jsfiddle.net/c88keve7/2/
You can set the renderBuffer property when creating your vector layer. See ol.layer.Vector:
renderBuffer: The buffer around the viewport extent used by the renderer when getting features from the vector source for the rendering or hit-detection. Recommended value: the size of the largest symbol, line width or label. Default is 100 pixels.
I am wondering how to place images on a line. For example, instead of a dotted or dashed line, I could include a symbol of a ship or a character (e.g. |) repeated along the line.
My current code:
line = new ol.geom.LineString([[0, 0], [100, 100]]);
lineStyle = new ol.style.Style({
stroke: new ol.style.Stroke({
color: 'black',
width: 5,
lineDash: [10, 10]
}),
});
lineFeature = new ol.Feature({
geometry: line,
});
lineFeature.setStyle(lineStyle);
. . .
map = new ol.Map({
layers: [
new ol.layer.Vector({
source: new ol.source.Vector({
features: [
lineFeature,
],
}),
})
],
. . .
EDIT 2:
Here is what my line looks like:
(See image)
Here is what it should look like:
(See image)
It could be like this, or pictures of anchors.
EDIT:
New style code (not working):
lineStyle = new ol.style.Style({
radius: 10,
images: './icon.png',
stroke: new ol.style.Stroke({
color: 'black',
width: 5,
lineDash: lineDash,
}),
});
Am I doing anything wrong?
EDIT 3:
I have figured out how to do this:
Using Blender, add a mesh and add vertices on where the vertices are on your line.
Convert the mesh to a curve (Alt-C).
Add a plane and add your image to it as a texture.
Scale the plane to the appropriate size relative to the line (S).
Add an Array modifier to the plane with the image and choose Fit Curve for Fit Type.
Set the Curve: to the name of the curve you created from the mesh.
Set the Relative Offset’s first box to the space between the dots (relative to the size of the dots)
Add a Curve modifier to the plane and choose the curve you created as the Object:.
Note: This may result in the images being deformed. If this occurs, follow these steps:
Duplicate the plane (Alt-D)
Remove the Array and Curve modifiers from the duplicate.
Parent the duplicate plane to the original plane.
Select the duplicate plane, then the original plane.
Press Ctrl-P.
Select Object.
In the original plane, go to the Object buttons (orange cube) and select Faces under Duplication.
This will place a copy of the plane at the center of each face.
There is currently no support for this in OpenLayers 3, I am also trying to find a mechanism that would work well and scale with many features. The only thing currently available in OpenLayers 3 to acheive this would be to use this technique, but it would greatly affect performance: http://boundlessgeo.com/2015/04/geometry-based-styling-openlayers-3/
A live example is available here:
http://openlayers.org/en/master/examples/line-arrows.html
To acheive the kind of style you want, you would have to compute points along the line for the given resolution and assign a ol.style.Icon for those points.
I guess it could be possible to implement more advanced stroke styles in OpenLayers 3, the following page demonstrates multiple techniques to render strokes with Canvas: http://perfectionkills.com/exploring-canvas-drawing-techniques/
lineStyle = new ol.style.Style({
image: new ol.style.Icon(({
opacity: 1,
size:20,
src: './icon.png'
})),
stroke: new ol.style.Stroke({
color: 'black',
width: 5,
lineDash: lineDash,
})
});
Visit these links to find more about this.
http://openlayers.org/en/v3.8.1/apidoc/ol.style.Style.html
http://openlayers.org/en/v3.6.0/apidoc/ol.style.Icon.html
Is it possible to make the symbolizer of a feature be a polygon?
Openlayers 3 has a ol.style.Circle and ol.style.RegularShape symbolizers for example. Is there something equivalent to a hypothetical ol.style.Polygon? Whereby you could make a dynamic symbolizer from multiple points?
The reason I want to do this is because I have markers on my map that are dynamically shaped depending on the data for that marker. It is possible to simply draw a ol.geom.Polygon at each point, but then they are not zoom independent. I want to have markers that are zoom independent, meaning that their size on the screen does not change when I zoom in or out.
And just to be clear, using raster images (for example in ol.style.Icon) is not possible. There are way too many markers in way too many shapes and colours in my project.
Yes, this is possible. ol.style.Style takes a geometry argument that you can use to overwrite the geometry that is used to render a feature.
var style = function(feature, resolution) {
// construct the polygon taking the resolution into account
var polygon = new ol.geom.Polygon(...);
return [
new ol.style.Style({
geometry: polygon,
stroke: ...
fill: ...
}),
];
};
Also see this question: Drawing a Speed Leader line in OpenLayers
I would like to replace a part of the image with my image in Opencv
I used
cvGetPerspectiveMatrix() with a warpmatrix and using cvAnd() and cvOr()
but could not get it to work
This is the code that is currently displaying the image and a white polygon for the replacement image. I would like to replace the white polygon for a pic with any dimension to be scaled and replaced with the region pointed.
While the code is in javacv I could convert it to java even if c code is posted
grabber.start();
while(isDisp() && (image=grabber.grab())!=null){
if (dst_corners != null) {// corners of the image to be replaced
CvPoint points = new CvPoint((byte) 0,dst_corners,0,dst_corners.length);
cvFillConvexPoly(image,points, 4, CvScalar.WHITE, 1, 0);//white polygon covering the replacement image
}
correspondFrame.showImage(image);
}
Any pointers to this will be very helpful.
Update:
I used warpmatrix with this code and I get a black spot for the overlay image
cvSetImageROI(image, cvRect(x1,y1, overlay.width(), overlay.height()));
CvPoint2D32f p = new CvPoint2D32f(4);
CvPoint2D32f q = new CvPoint2D32f(4);
q.position(0).x(0);
q.position(0).y(0);
q.position(1).x((float) overlay.width());
q.position(1).y(0);
q.position(2).x((float) overlay.width());
q.position(2).y((float) overlay.height());
q.position(3).x(0);
q.position(3).y((float) overlay.height());
p.position(0).x((int)Math.round(dst_corners[0]);
p.position(0).y((int)Math.round(dst_corners[1]));
p.position(1).x((int)Math.round(dst_corners[2]));
p.position(1).y((int)Math.round(dst_corners[3]));
p.position(3).x((int)Math.round(dst_corners[4]));
p.position(3).y((int)Math.round(dst_corners[5]));
p.position(2).x((int)Math.round(dst_corners[6]));
p.position(2).y((int)Math.round(dst_corners[7]));
cvGetPerspectiveTransform(q, p, warp_matrix);
cvWarpPerspective(overlay, image, warp_matrix);
I get a black spot for the overlay image and even though the original image is a polygon with 4 vertices the overlay image is set as a rectangle. I believe this is because of the ROI. Could anyone please tell me how to fit the image as is and also why I am getting a black spot instead of the overlay image.
I think cvWarpPerspective(link) is what you are looking for.
So instead of doing
CvPoint points = new CvPoint((byte) 0,dst_corners,0,dst_corners.length);
cvFillConvexPoly(image,points, 4, CvScalar.WHITE, 1, 0);//white polygon covering the replacement image
Try
cvWarpPerspective(yourimage, image, M, image.size(), INTER_CUBIC, BORDER_TRANSPARENT);
Where M is the matrix you get from cvGetPerspectiveMatrix
One way to do it is to scale the pic to the white polygon size and then copy it to the grabbed image setting its Region of Interest (here is a link explaining the ROI).
Your code should look like this:
resize(pic, resizedImage, resizedImage.size(), 0, 0, interpolation); //resizedImage should have the points size
cvSetImageROI(image, cvRect(the points coordinates));
cvCopy(resizedImage,image);
cvResetImageROI(image);
I hope that helps.
Best regards,
Daniel