I have 4 coordinates of rect.
like
north="55.9504356" south="55.5485293" east="38.1289043" west="37.1044291"
how i can set map position in this rectangle?
You should convert your coordinates. Try to obtain a center of rect somehow. Here's the sample of my code:
CLLocationCoordinate2D coordinate = {[neighborhood.Latitude doubleValue], [neighborhood.Longitude doubleValue]};
MKCoordinateRegion region = MKCoordinateRegionMakeWithDistance(coordinate, 15000, 15000);
[self.mapView setRegion:region animated:NO];
as you can see you point out a center of rect and the distance from center in meters.
google goecoding gives me viewport <LatLonBox north="55.9504356" south="55.5485293" east="38.1289043" west="37.1044291"/> and center of region Russia, Moscow.
CLLocationCoordinate2D centerOfRegion = CLLocationCoordinate2DMake([data.coordinatesLongitude doubleValue],[data.coordinatesLatitude doubleValue]); //37.6166667,55.7500000
//N+E S+W for get distance between
double lat1 = [[data.squareArray objectAtIndex:0] doubleValue];
double lng1 = [[data.squareArray objectAtIndex:2] doubleValue];
double lat2 = [[data.squareArray objectAtIndex:1] doubleValue];
double lng2 = [[data.squareArray objectAtIndex:3] doubleValue];
CLLocation *firstLocation = [[[CLLocation alloc] initWithLatitude:lat1 longitude:lng1] autorelease];
CLLocation *secondLocation = [[[CLLocation alloc] initWithLatitude:lat2 longitude:lng2] autorelease];
// and /2 to make a little smaller viewport
CLLocationDistance distance = [secondLocation distanceFromLocation:firstLocation];
[map setRegion:MKCoordinateRegionMakeWithDistance(centerOfRegion, distance/2, distance/2)];
so a got centered region and normaly size of region.
My solution is so, hopeits can help somebody else.
Related
I have an image in a CALayer (using the CALayers contents property). A CALayer has a transform property that can be use to scale and rotate. I can use that transform without difficulty when the CALayer is still.
But when I try to drag the CALayer (using mouseDragged:(NSEvent *)theEvent), then it all fells apart (the image gets flattened out as I drag).
-(void)mouseDragged:(NSEvent *)theEvent {
CGPoint loc = [self convertPoint:theEvent.locationInWindow fromView:nil];
CGPoint deltaLoc = ccpSub(loc, downLoc); // subtract two points
CGPoint newPos = ccpAdd(startPos, deltaLoc); // adds two points
[layer changePosition:newPos];
...
}
In the layer
-(void)changePosition:(CGPoint)newPos {
//prevent unintended animation actions
self.actions = #{#"position": [NSNull null]};
CGSize size = self.frame.size;
CGRect newRect = CGRectMake(newPos.x, newPos.y, size.width, size.height);
self.frame = newRect;
}
The problem is that I use CALayer's frame to dynamically change the location of the CALayer as I drag, but when the rotation angle is not zero, then the frame is not longer parallel to x and y axis. What is the best way to fix this problem?
One way to do it is to regenerate transforms for each incremental movement.
-(void)mouseDragged:(CGPoint)deltaLoc start:(CGPoint)startPos {
CGPoint newPos = ccpAdd(startPos, deltaLoc);
[self changePosition:newPos];
}
-(void)changePosition:(CGPoint)newPos {
//prevent unintended animation actions
self.actions = #{#"position": [NSNull null]};
double angle = [[self valueForKeyPath: #"transform.rotation"] doubleValue];
double scaleX = [[self valueForKeyPath: #"transform.scale.x"] doubleValue];
double scaleY = [[self valueForKeyPath: #"transform.scale.y"] doubleValue];
self.transform = CATransform3DIdentity;
CGSize size = self.frame.size;
CGRect newRect = CGRectMake(newPos.x, newPos.y, size.width, size.height);
self.frame = newRect;
[self applyTransformRotation:angle scale:ccp(scaleX, scaleY)];
}
-(void)applyTransformRotation:(double)angle scale:(CGPoint)scale {
self.transform = CATransform3DMakeRotation(angle, 0, 0, 1);
self.transform = CATransform3DScale(self.transform, scale.x, scale.y, 1);
}
I do not know if this is the most efficient way to do it, but it definitely works.
I have to add annotation view image as a car. I am able to move that car according to the locations I am getting from server. But I am facing problem when I have applied code for rotation of car. Every time, car is turning to new location, it moves and again it goes to its original position(car does not face to front).then again it turns,moves and goes to original position. It should move straight. I want car should face to front and It should turn only when actually there is turning. My code is:
oldLocation.latitude = [[_lat objectAtIndex:i] doubleValue];
oldLocation.longitude = [[_longitude objectAtIndex:i] doubleValue];
newLocation.latitude = [[latNew objectAtIndex:i] doubleValue];
newLocation.longitude = [[longNew objectAtIndex:i] doubleValue];
float getAngle = [self angleFromCoordinate:oldLocation toCoordinate:newLocation];
[UIView animateWithDuration:2 animations:^{
MKAnnotationView *annotationView = (MKAnnotationView *[self.mapView viewForAnnotation:myAnnotation[i]];
annotationView.transform = CGAffineTransformMakeRotation(getAngle);
myAnnotation[i].coordinate = newLocation;
}];
}
- (float)angleFromCoordinate:(CLLocationCoordinate2D)first
toCoordinate:(CLLocationCoordinate2D)second {
float deltaLongitude = second.longitude - first.longitude;
float deltaLatitude = second.latitude - first.latitude;
float angle = (M_PI * .5f) - atan(deltaLatitude / deltaLongitude);
if (deltaLongitude > 0) return angle;
else if (deltaLongitude < 0) return angle + M_PI;
else if (deltaLatitude < 0) return M_PI;
return 0.0f;
}
I'm building a application in whom one of the features will be shoving geographic coordinates on a custom UIImageView. I'm bad at math so I cant seem to get the right values. This is what I'm doing:
I have a image that is 2048x2048 and I put it in a UIScrollView and when I get coordinates, let's say "Sydney -33.856963, 151.215219" I turn them into a UIView coordinates (x,y)
- (void)viewDidLoad
{
[super viewDidLoad];
scrollView = [[UIScrollView alloc]initWithFrame:CGRectMake(0, 0, self.view.frame.size.width,self.view.frame.size.height)];
scrollView.delegate = self;
scrollView.showsVerticalScrollIndicator = YES;
scrollView.scrollEnabled = YES;
scrollView.userInteractionEnabled = YES;
[scrollView setBounces:NO];
scrollView.minimumZoomScale = 0.5;
scrollView.maximumZoomScale = 100.0;
mainImageView = [[UIImageView alloc]initWithFrame:CGRectMake(0, 0, IMAGE_SIZE, IMAGE_SIZE)];
mainImageView.image = [UIImage imageNamed:#"map.jpg"];
mainImageView.contentMode = UIViewContentModeScaleAspectFit;
tipScroll.contentSize = CGSizeMake(IMAGE_SIZE, IMAGE_SIZE);
[scrollView addSubview:mainImageView];
[self.view addSubview:scrollView];
NSString* fileContents = #"-33.856963,151.215219";
NSArray* pointStrings = [fileContents componentsSeparatedByCharactersInSet:[NSCharacterSet whitespaceAndNewlineCharacterSet]];
for (int i = 0; i<[pointStrings count]; i++) {
NSArray* latLonArr = [currentPointString componentsSeparatedByCharactersInSet:[NSCharacterSet characterSetWithCharactersInString:#","]];
[self getCoordinates:latLonArr];
}
}
-(void)getCoordinates:(NSArray *)latLonArr{
double comparatorWidth = IMAGE_SIZE/360.0f;
double comparatorHeight = IMAGE_SIZE/180.0f;
double Xl = [[latLonArr objectAtIndex:1] doubleValue]; //151.215219
double Yl = [[latLonArr objectAtIndex:0] doubleValue]; //-33.856963
coordX = (Xl+180.0f)*comparatorWidth;
coordY = (90.0f-Yl)*comparatorHeight;
UIImage *image=[UIImage imageNamed:[NSString stringWithFormat:#"star.png"]];
imageView=[[UIImageView alloc] init];
[imageView setFrame:CGRectMake(coordX,coordY,10,10)];
[imageView setImage:image];
[scrollView addSubview:imageView];
}
The further I go from the center coordinates (0,0) the more the points are not accurate. If I have coordinates for a city in West Africa it will be right on spot, but Sydney is a lot off. How can I fix this?
I think the problem is that the earth is not flat. That means that you can not simple convert geo coordinates to 2-dimensional system of the view. http://en.wikipedia.org/wiki/Geographic_coordinate_system
Check this question and the correct answer:
Converting longitude/latitude to X/Y coordinate
Look at the white horizontal lines on the image you posted. They're not evenly spaced out - they get wider towards the bottom of the image. This means that your map image is not made using an Equirectangular projection, and is probably a Mercator projection image.
The code you have posted which converts lat/long to Y/X just by offset and scaling would only work for Equirectangular projection images.
For mercator projections, the conversion is more complex. Please see Covert latitude/longitude point to a pixels (x,y) on mercator projection.
So you have two options:
A) Use equirectangular projection map images
B) Continue using Mercator map images, and fix your lat/long -> Y/X conversion algorithm
I'm drawing my graph view using UIBezierPathmethods and coretext. I use addQuadCurveToPoint:controlPoint: method to draw curves on graph. I also use CATiledLayer for the purpose of rendering graph with large data set on x axis. I draw my whole graph in an image context and in drawrect: method of my view I draw this image in my whole view. Following is my code.
- (void)drawImage{
UIGraphicsBeginImageContextWithOptions(self.frame.size, NO, 0.0);
// Draw Curves
[self drawDiagonal];
UIImage *screenshot = UIGraphicsGetImageFromCurrentImageContext();
[screenshot retain];
UIGraphicsEndImageContext();
}
- (void)drawRect:(CGRect)rect{
NSLog(#"Draw iN rect with Bounds: %#",NSStringFromCGRect(rect));
[screenshot drawInRect:self.frame];
}
However in screenshot the curves drawn between two points are not smooth. I've also set the Render with Antialiasing to YES in my info plist. Please see screenshot.
We'd have to see how you construct the UIBezierPath, but in my experience, for smooth curves, the key issue is whether the slope of the line between a curve's control point and the end point of that particular segment of the curve is equal to the slope between the next segment of the curve's start point and its control point. I find that easier to draw general smoooth curves using addCurveToPoint rather than addQuadCurveToPoint, so that I can adjust the starting and ending control points to satisfy this criterion more generally.
To illustrate this point, the way I usually draw UIBezierPath curves is to have an array of points on the curve, and the angle that the curve should take at that point, and then the "weight" of the addCurveToPoint control points (i.e. how far out the control points should be). Thus, I use those parameters to dictate the second control point of a UIBezierPath and the first controlPoint of the next segment of the UIBezierPath. So, for example:
#interface BezierPoint : NSObject
#property CGPoint point;
#property CGFloat angle;
#property CGFloat weight;
#end
#implementation BezierPoint
- (id)initWithPoint:(CGPoint)point angle:(CGFloat)angle weight:(CGFloat)weight
{
self = [super init];
if (self)
{
self.point = point;
self.angle = angle;
self.weight = weight;
}
return self;
}
#end
And then, an example of how I use that:
- (void)loadBezierPointsArray
{
// clearly, you'd do whatever is appropriate for your chart.
// this is just a unclosed loop. But it illustrates the idea.
CGPoint startPoint = CGPointMake(self.view.frame.size.width / 2.0, 50);
_bezierPoints = [NSMutableArray arrayWithObjects:
[[BezierPoint alloc] initWithPoint:CGPointMake(startPoint.x, startPoint.y)
angle:M_PI_2 * 0.05
weight:100.0 / 1.7],
[[BezierPoint alloc] initWithPoint:CGPointMake(startPoint.x + 100.0, startPoint.y + 70.0)
angle:M_PI_2
weight:70.0 / 1.7],
[[BezierPoint alloc] initWithPoint:CGPointMake(startPoint.x, startPoint.y + 140.0)
angle:M_PI
weight:100.0 / 1.7],
[[BezierPoint alloc] initWithPoint:CGPointMake(startPoint.x - 100.0, startPoint.y + 70.0)
angle:M_PI_2 * 3.0
weight:70.0 / 1.7],
[[BezierPoint alloc] initWithPoint:CGPointMake(startPoint.x + 10.0, startPoint.y + 10)
angle:0.0
weight:100.0 / 1.7],
nil];
}
- (CGPoint)calculateForwardControlPoint:(NSUInteger)index
{
BezierPoint *bezierPoint = _bezierPoints[index];
return CGPointMake(bezierPoint.point.x + cosf(bezierPoint.angle) * bezierPoint.weight,
bezierPoint.point.y + sinf(bezierPoint.angle) * bezierPoint.weight);
}
- (CGPoint)calculateReverseControlPoint:(NSUInteger)index
{
BezierPoint *bezierPoint = _bezierPoints[index];
return CGPointMake(bezierPoint.point.x - cosf(bezierPoint.angle) * bezierPoint.weight,
bezierPoint.point.y - sinf(bezierPoint.angle) * bezierPoint.weight);
}
- (UIBezierPath *)bezierPath
{
UIBezierPath *path = [UIBezierPath bezierPath];
BezierPoint *bezierPoint = _bezierPoints[0];
[path moveToPoint:bezierPoint.point];
for (NSInteger i = 1; i < [_bezierPoints count]; i++)
{
bezierPoint = _bezierPoints[i];
[path addCurveToPoint:bezierPoint.point
controlPoint1:[self calculateForwardControlPoint:i - 1]
controlPoint2:[self calculateReverseControlPoint:i]];
}
return path;
}
When I render this into a UIImage (using the code below), I don't see any softening of the image, but admittedly the images are not identical. (I'm comparing the image rendered by capture against that which I capture manually with a screen snapshot by pressing power and home buttons on my physical device at the same time.)
If you're seeing some softening, I would suggest renderInContext (as shown below). I wonder if you writing the image as JPG (which is lossy). Maybe try PNG, if you used JPG.
- (void)drawBezier
{
UIBezierPath *path = [self bezierPath];
CAShapeLayer *oval = [[CAShapeLayer alloc] init];
oval.path = path.CGPath;
oval.strokeColor = [UIColor redColor].CGColor;
oval.fillColor = [UIColor clearColor].CGColor;
oval.lineWidth = 5.0;
oval.strokeStart = 0.0;
oval.strokeEnd = 1.0;
[self.view.layer addSublayer:oval];
}
- (void)capture
{
UIGraphicsBeginImageContextWithOptions(self.view.frame.size, NO, 0.0);
CGContextRef context = UIGraphicsGetCurrentContext();
[self.view.layer renderInContext:context];
UIImage *screenshot = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();
// save the image
NSData *data = UIImagePNGRepresentation(screenshot);
NSString *documentsPath = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES)[0];
NSString *imagePath = [documentsPath stringByAppendingPathComponent:#"image.png"];
[data writeToFile:imagePath atomically:YES];
// send it to myself so I can look at the file
NSURL *url = [NSURL fileURLWithPath:imagePath];
UIActivityViewController *controller = [[UIActivityViewController alloc] initWithActivityItems:#[url]
applicationActivities:nil];
[self presentViewController:controller animated:YES completion:nil];
}
So I have an NSFont, and I want to get the maximum dimensions for any characters, ie. the pitch and letter height. [font maximumAdvancement] seems to return an NSSize of {pitch, 0}, so that's not helping. Bounding rect doesn't seem to work either, and the suggestion from jwz's similar question of creating a bezier path, appending a glyph and getting the bounding rectange is also giving me back {0, 0}. What gives here?
UPDATE: The code I'm using to get the bezier size is this:
NSBezierPath *bezier = [NSBezierPath bezierPath];
NSGlyph g;
{
NSTextStorage *ts = [[NSTextStorage alloc] initWithString:#" "];
[ts setFont:font];
NSLayoutManager *lm = [[NSLayoutManager alloc] init];
NSTextContainer *tc = [[NSTextContainer alloc] init];
[lm addTextContainer:tc];
[tc release]; // lm retains tc
[ts addLayoutManager:lm];
[lm release]; // ts retains lm
g = [lm glyphAtIndex:0];
[ts release];
}
NSPoint pt = {0.0f};
[bezier moveToPoint:pt];
[bezier appendBezierPathWithGlyph:g inFont:font];
NSRect bounds = [bezier bounds];
The glyph for the space character doesn't have any subpaths, so of course its bounds have size NSZeroSize. Try -[NSFont boundingRectForFont] instead.