MKGeometry.h

/*
 *  MKGeometry.h
 *  MapKit
 *
 *  Created by Rick Fillion on 7/11/10.
 *  Copyright 2010 Centrix.ca. All rights reserved.
 *
 */

#import <CoreLocation/CoreLocation.h>

typedef struct {
    CLLocationDegrees latitudeDelta;
    CLLocationDegrees longitudeDelta;
} MKCoordinateSpan;

typedef struct {
    CLLocationCoordinate2D center;
    MKCoordinateSpan span;
} MKCoordinateRegion;


static inline MKCoordinateSpan MKCoordinateSpanMake(CLLocationDegrees latitudeDelta, CLLocationDegrees longitudeDelta)
{
    MKCoordinateSpan span;
    span.latitudeDelta = latitudeDelta;
    span.longitudeDelta = longitudeDelta;
    return span;
}

static inline MKCoordinateRegion MKCoordinateRegionMake(CLLocationCoordinate2D centerCoordinate, MKCoordinateSpan span)
{
    MKCoordinateRegion region;
    region.center = centerCoordinate;
    region.span = span;
    return region;
}

// An MKMapPoint is a coordinate that has been projected for use on the
// two-dimensional map.  An MKMapPoint always refers to a place in the world
// and can be converted to a CLLocationCoordinate2D and back.
typedef struct {
    double x;
    double y;
} MKMapPoint;

typedef struct {
    double width;
    double height;
} MKMapSize;

typedef struct {
    MKMapPoint origin;
    MKMapSize size;
} MKMapRect;

/*
// MKZoomScale provides a conversion factor between MKMapPoints and screen points.
// When MKZoomScale = 1, 1 screen point = 1 MKMapPoint.  When MKZoomScale is
// 0.5, 1 screen point = 2 MKMapPoints.
typedef CGFloat MKZoomScale;

 */


extern const MKMapSize MKMapSizeWorld;
// The rect that contains every map point in the world.
extern  const MKMapRect MKMapRectWorld;

 
// Conversion between unprojected and projected coordinates
extern  MKMapPoint MKMapPointForCoordinate(CLLocationCoordinate2D coordinate);
extern  CLLocationCoordinate2D MKCoordinateForMapPoint(MKMapPoint mapPoint);


// Conversion between distances and projected coordinates
extern  CLLocationDistance MKMetersPerMapPointAtLatitude(CLLocationDegrees latitude);
extern  double MKMapPointsPerMeterAtLatitude(CLLocationDegrees latitude);

/*
extern  CLLocationDistance MKMetersBetweenMapPoints(MKMapPoint a, MKMapPoint b);

extern  const MKMapRect MKMapRectNull;*/

// Geometric operations on MKMapPoint/Size/Rect.  See CGGeometry.h for 
// information on the CGFloat versions of these functions.
static inline MKMapPoint MKMapPointMake(double x, double y) {
    return (MKMapPoint){x, y};
}
static inline MKMapSize MKMapSizeMake(double width, double height) {
    return (MKMapSize){width, height};
}

static inline MKMapRect MKMapRectMake(double x, double y, double width, double height) {
    return (MKMapRect){ MKMapPointMake(x, y), MKMapSizeMake(width, height) };
}
static inline double MKMapRectGetMinX(MKMapRect rect) {
    return rect.origin.x;
}
static inline double MKMapRectGetMinY(MKMapRect rect) {
    return rect.origin.y;
}
static inline double MKMapRectGetMidX(MKMapRect rect) {
    return rect.origin.x + rect.size.width / 2.0;
}
static inline double MKMapRectGetMidY(MKMapRect rect) {
    return rect.origin.y + rect.size.height / 2.0;
}
static inline double MKMapRectGetMaxX(MKMapRect rect) {
    return rect.origin.x + rect.size.width;
}
static inline double MKMapRectGetMaxY(MKMapRect rect) {
    return rect.origin.y + rect.size.height;
}
static inline double MKMapRectGetWidth(MKMapRect rect) {
    return rect.size.width;
}
static inline double MKMapRectGetHeight(MKMapRect rect) {
    return rect.size.height;
}
static inline BOOL MKMapPointEqualToPoint(MKMapPoint point1, MKMapPoint point2) {
    return point1.x == point2.x && point1.y == point2.y;
}
static inline BOOL MKMapSizeEqualToSize(MKMapSize size1, MKMapSize size2) {
    return size1.width == size2.width && size1.height == size2.height;
}
static inline BOOL MKMapRectEqualToRect(MKMapRect rect1, MKMapRect rect2) {
    return
    MKMapPointEqualToPoint(rect1.origin, rect2.origin) &&
    MKMapSizeEqualToSize(rect1.size, rect2.size);
}

static inline BOOL MKMapRectIsNull(MKMapRect rect) {
    return isinf(rect.origin.x) || isinf(rect.origin.y);
}
static inline BOOL MKMapRectIsEmpty(MKMapRect rect) {
    return MKMapRectIsNull(rect) || (rect.size.width == 0.0 && rect.size.height == 0.0);
}

static inline NSString *MKStringFromMapPoint(MKMapPoint point) {
    return [NSString stringWithFormat:@"{%.1f, %.1f}", point.x, point.y];
}

static inline NSString *MKStringFromMapSize(MKMapSize size) {
    return [NSString stringWithFormat:@"{%.1f, %.1f}", size.width, size.height];
}

static inline NSString *MKStringFromMapRect(MKMapRect rect) {
    return [NSString stringWithFormat:@"{%@, %@}", MKStringFromMapPoint(rect.origin), MKStringFromMapSize(rect.size)];
}
/*
extern MKMapRect MKMapRectUnion(MKMapRect rect1, MKMapRect rect2);
extern MKMapRect MKMapRectIntersection(MKMapRect rect1, MKMapRect rect2);
extern MKMapRect MKMapRectInset(MKMapRect rect, double dx, double dy);
extern MKMapRect MKMapRectOffset(MKMapRect rect, double dx, double dy);
extern void MKMapRectDivide(MKMapRect rect, MKMapRect *slice, MKMapRect *remainder, double amount, CGRectEdge edge);

extern BOOL MKMapRectContainsPoint(MKMapRect rect, MKMapPoint point);
extern BOOL MKMapRectContainsRect(MKMapRect rect1, MKMapRect rect2);
extern BOOL MKMapRectIntersectsRect(MKMapRect rect1, MKMapRect rect2);
*/

extern MKCoordinateRegion MKCoordinateRegionForMapRect(MKMapRect rect);

/*
extern BOOL MKMapRectSpans180thMeridian(MKMapRect rect);
// For map rects that span the 180th meridian, this returns the portion of the rect
// that lies outside of the world rect wrapped around to the other side of the
// world.  The portion of the rect that lies inside the world rect can be 
// determined with MKMapRectIntersection(rect, MKMapRectWorld).
extern MKMapRect MKMapRectRemainder(MKMapRect rect);
 */