I have a problem. I created sinusoide using code: sinusoide and increased the thickness with path.lineWidth. I also added a dot to the screen (CAShapeLayer). I need to check if my dot is in the sinusoidal. I checked the available function UIBezierPath.contain. Unfortunately, it does not considering the lineWidth. I also checked by color if the pixel on the screen contains color but unfortunately it is very slow and takes 100% CPU. Whether there is any other quick way to find out if the dot is in the UIBezierPath?
Use copy(strokingWithWidth:lineCap:lineJoin:miterLimit:transform:) to create a stroked copy of the path. Then use contains on the copy to test the center of the dot.
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I have stumbled upon an interesting problem and I am not sure how to solve it. I have a line graph on which data points are marked with circular dots. At the moment I am creating one CAShapeLayer for the line itself and also CAShapeLayer for each dot.
The line is being animated with the strokeEnd animation key path. And it is working. However, the slightly negative effect is that once I open the graph I see all the data points already drawn and then a line is being animated through them.
Ideally I would like to change this behaviour in such a way that at the beginning nothing is shown and as the line gets animated data points are being drawn once the line passes through them.
I was thinking about this problem for some time now and I cannot find an elegant way of solving it. It seems to me that there should be a fairly easy way of achieving what I want. Maybe I should create a compounded path (but then how do I specify that a line needs to be stroked whereas dots need to be filled?).
Could anyone please guide me in the right direction?
There are lots of ways to handle this.
Assuming that the X increments of your graph are constant, and you're using linear timing, you could simply divide the total animation time by the number of data-points, and calculate the times when you need to add points to the graph when the line progresses to that X position. Simply add dot shape layers to the parent view's layer at the appropriate time intervals.
You could also change your drawing method to add new line segments to your graph path one at a time, on a timer, and add dot shapes at the same time. That would give you a step-by-step animation rather than a smooth line drawing.
I'm trying to create a sort of progress bar class that fills along a UIBezierPath as it progresses. I need to stroke a UIBezierPath with a controlled animation.
I think I could implement this if I could truncate the path to a precise portion of its original length. Is this possible? Is there another method I can use to precisely control the animated stroking of a path?
I've seen this question, but the answer seems to address finding the points at the beginning and end of each element. I'd need to get a list of points at a pixel-by-pixel level for a list of points to be a viable solution.
I believe I'm looking for the strokeEnd property.
Hello: Currently in my project, I'm using OBShapedButton to process touches on a lot of objects that overlap (it's a map with each territory its own separate object). Basically, this library prevents a touch from being processed on a transparent point on the given view.
I'm attempting to add a border effect to just the edges of the opaque part of the UIImage (and adding a semi-transparent overlay above that). Something to the effect of this:
Which can be simplified to this (example of one image):
I am currently using MGImageUtilities to color in the opaque parts of territories using this line:
[territory setImage:[[territory image] imageTintedWithColor:tint]];
The problem is that I'm not sure how to just color the borders (which can be any shape). I've looked at this link already, but haven't been able to come up with anything.
Thanks in advance for the help!
Terribly hacky, but use MGImageUtilities' UIImage+ProportionalFill with scale resizing to create a slightly larger image, UIImage+Tint to red, and stack below.
The library you are using doesn't actually specify a shape layer. It uses alpha values from the PNGs that you give it.
Could you use a different 'highlighted' or 'selected' PNG that adds the border effect you are looking for?
Otherwise, it you will have to generate a UIBezierPath from your PNG image, which sounds like a very computationally intensive operation. At that point, I might question whether this library meets your needs.
How do you draw a curved path (similar to the one showed below) that passes through a set of points in an iOS app.
UIBazierPath
http://developer.apple.com/library/ios/#documentation/uikit/reference/UIBezierPath_class/Reference/Reference.html
You create it, add your points to create the curve, set the required line dash, then use - (void)stroke to draw it.
On iOS, I'm using core-plot to draw a line graph. I want the line to be bordered top and bottom with a solid color and a different color in the middle, a striping effect. This cannot be done using CPTLineStyle, so I created a custom line style that uses CGContextSetStrokePattern to draw the line.
I thought I achieve the desired effect by creating a striped image and using it as the stroke pattern. This works, but the image orientation does not follow the direction of the path. The stripes are always horizontal even if the direction of the path is 45 degrees.
How can I tell Quartz auto rotate the pattern fill such that it follows the vector direction of the graph segment? Or alternatively, how can I get core-plot to do this for me?
We recently added the lineGradient property to CPTLineStyle that gives you a very flexible way to do this. See the "Gradient Scatter Plot" demo in the Plot Gallery example app.
Note that this change was added after the 1.3 release and is not part of a downloadable release yet. You will need to pull the latest code with Mercurial to get the change or wait for the next release.
The best solution I've found is to use two plots. The first with the wider line style the second with the narrower one. That achieves the desired effect.