I have two polygons that are next to each other (left image). After performing a union of the two polygons, I have a single polygon with outlines similar to the left image. What I am looking for is a way to remove the shared edges of the two polygons, as shown on the right. I am working with arcobjects (.net) and arcdesktop 10.1. Hopefully there's a nice built-in method to achieve this. Thanks.
There is indeed a nice built-in method - you're looking for the Dissolve tool.
There is an example in the ArcObjects help, this may help you.
[Creating a union of several polygons]
http://help.arcgis.com/en/sdk/10.0/arcobjects_net/conceptualhelp/index.html#/d/00010000009t000000.htm
I got this to work with the Integrate tool. It merges two polygons and remove any two edges that are near each other.
Related
I am totally new to openscad.
I am trying to generate two overlapping polygons (2D). I would just like to observe the outlines of both shapes at the same time.
I have managed to generate two different shapes. Although the shapes overlap, the renderer appears to show the outline of the combined shape with the inner part is filled in with colour.
How might I achieve my goal if the shapes were simply two overlapping squares?
I would be glad to see your code to understand exactly what you're trying to describe.
In any case, you must know first that openscad have several rendering types:
the f5 one is the quicker and doesn't really calculates the final result, only its image on the screen (that's why you cannot export with it)
the f6 one which does all the calculation of the points of the mesh and then render it (that's what you do to export)
the debug ones that are similar to f5
I think f5 could be your solution but it will look a bit "glitchy" because of the superposition of the two shapes. The fact is that I don't think openscad is made for what you want to do because you can consider that all that you put in your script is in a big union() block so when you press f6 all the independent shapes are combined into one and I don't think there is a way to prevent that. I should add that I think that the 2D functions of openscad are probably made to be used with the extrude functions to make 3D volumes for which the overlapping doesn't have a lot of sense.
I have two data layers, one with points and one with polygons. Both layers have ID's and I would like to check whether the points with ID x lay inside or outside the polygon with ID x.
Does someone know how to do this?
Thanks,
Marie
One potential solution which gives you a comma separated list in the python console is to run a small script from the python console:
mapcanvas = iface.mapCanvas()
layers = mapcanvas.layers()
for a in layers[0].getFeatures():
for b in layers[1].getFeatures():
if a.geometry().intersects(b.geometry()):
print a.id(),",",b.id()
This should produce a result of cases where one feature intersects the other. The order of the layers did not matter in my testing, however, both layers had to use the same coordinate reference system, so you might need to re-project your data if both layers have different reference systems. This worked for points in polygons and polygons intersecting polygons (I'm sure it would work with lines as well).
Answers such as this: https://gis.stackexchange.com/questions/168266/pyqgis-a-geometry-intersectsb-geometry-wouldnt-find-any-intersections may help with further refinement of such a script, and was a primary source on this answer.
I'm making a chess piece (a bishop) and I am trying to make the top notch.
For this purpose, I made a new cube, resized it and put on the place to make the cut.
I want to make a cut using a modifier: Boolean, intersecting the two objects.
The problem I am facing is that while intersecting, the top UV Sphere that simulates the 'hat' of the bishop disappears.
What I did so far:
- Remove Doubles
- CTRL+J to join Bishop+Hat(UV Sphere) to make 1 component
Nothing helped and when trying to intersect, the UVSphere-hat disappears.
Why? How to solve?
Here is the bishop before modifier, with hat:
Here is the .blend file to catch the problem faster:
Thank you for your help :-)
The boolean modifier offers two different solvers that produce different results. You want the intersect operation with the carve solver. You also want to hide the cube that you are using for the intersection otherwise you won't see the hole that it has cut out.
Just to go straight to the point I'll add the reply here and select sambler's excellent answer as right.
In my case the Cube which was going to intersect with the bishop HAD NEGATIVE SCALE.
If you have similar problems, check if your objects scale/parameters have negative parameters
do you know how can I select a geometry with Three.js?
ve you never seen something like that?
I searched for many days but all examples I found don't work and are legacy coded. I would have to be able to select a geometry with the mouse and move it like in a drag and drop.. Maybe better select a Mesh, cause there are a lot of composed shapes. It's not fundamental move it with mouse, I can do it with fields, so at least to know where is the feature to select a Geometry, if there is, I couldn't find it.. thanks
http://mrdoob.github.com/three.js/examples/webgl_interactive_draggablecubes.html
If you need to select to color the mesh of the 3D model, use MeshLambertMaterial.js when creating the scene.
http://mrdoob.github.com/three.js/examples/webgl_interactive_cubes.html
I am interested in using the CGContextEOFillPath feature provided by apple. I am guessing with the way the EOFill works, it probably has a way to take the filled in areas and calculate an area.
So my question is does anyone know of a way to use CGContextEOFillPath and find the area of the filled in sections.
If this isn't something that is easily done, maybe some pointers to a better way of doing this would be helpful. Though I need to use the EO style graphing.
Thanks.
What do you mean "Calculate the area"?
As in calculate the surface area of a complex shape?
It depends on your shapes.
Are they all polygons?
What about circles?
There are well known formulas for calculating the area of a polygon. (Wikipedia has it) Part of that calculation involves using an ABS() function because shapes drawn "counterclockwise" have the opposite sign as those drawn "clockwise". If you're looking to simulate the EO behavior, you can simply ignore the sign change, because, for you, it's desirable.
If you have more complicated shapes that involve curves, then you need to break the problem down into multiple parts - one part to solve for polygons - one to solve for circles - one to solve for other shapes, etc.