RFGeometry.h

/*!
 RFGeometry
 RFKit
 
 Math and Graphics helper
 
 Copyright (c) 2012-2016, 2018 BB9z
 https://github.com/BB9z/RFKit
 
 The MIT License (MIT)
 http://www.opensource.org/licenses/mit-license.php
 */

#import "RFRuntime.h"

#pragma mark - Const
#ifndef RFMathNotChange
#   define RFMathNotChange CGFLOAT_MAX
#endif

extern const CGPoint CGPointNotChange;
extern const CGRect  CGRectNotChange;
extern const CGSize  CGSizeNotChange;

#pragma mark - Anchor
typedef NS_ENUM(NSInteger, RFResizeAnchor) {
	RFResizeAnchorCenter = 0,
    RFResizeAnchorTop,
    RFResizeAnchorBottom,
    RFResizeAnchorLeft,
    RFResizeAnchorRight,
    RFResizeAnchorTopLeft,
    RFResizeAnchorTopRight,
    RFResizeAnchorBottomLeft,
    RFResizeAnchorBottomRight,
} ;

typedef NS_ENUM(NSInteger, RFAlignmentAnchor) {
	RFAlignmentAnchorCenter = 0,
    RFAlignmentAnchorTop,
    RFAlignmentAnchorBottom,
    RFAlignmentAnchorLeft,
    RFAlignmentAnchorRight,
    RFAlignmentAnchorTopLeft,
    RFAlignmentAnchorTopRight,
    RFAlignmentAnchorBottomLeft,
    RFAlignmentAnchorBottomRight,
} ;

#pragma mark -
#pragma mark CGPoint
CGPoint	CGPointMid(CGPoint a, CGPoint b);
CGFloat	CGPointDistance(CGPoint a, CGPoint b);
CGPoint CGPointAtLineRatio(CGPoint start, CGPoint end, CGFloat ratio);
CGPoint CGPointOfRectCenter(CGRect a);


#pragma mark CGSize
CGSize	CGSizeFromPoints(CGPoint a, CGPoint b);
CGSize	CGSizeScaled(CGSize original, double scale);


#pragma mark CGRect
typedef NS_ENUM(NSInteger, RFCGRectChangeFlag) {
	RFCGRectChangeX = 0,
	RFCGRectChangeY,
	RFCGRectChangeWidth,
	RFCGRectChangeHeight
};

CGRect CGRectMakeWithPoints(CGPoint a, CGPoint b);
CGRect CGRectMakeWithCenterAndSize(CGPoint centerPoint, CGSize rectSize);

CGRect CGRectResize(CGRect original, CGSize newSize, RFResizeAnchor resizeAnchor);

// center not changed
CG_INLINE CGRect CGRectScaled(CGRect original, double scale) {
    return CGRectResize(original, CGSizeMake(original.size.width *scale, original.size.height *scale), RFResizeAnchorCenter);
}
CGRect CGRectChange(CGRect original, RFCGRectChangeFlag flag, CGFloat newValue);

#pragma mark CGAngle
// radian measure
typedef CGFloat CGAngle;
CGAngle	CGAngleFromPoints(CGPoint start, CGPoint end);
CGFloat	CGAngleDegrees(CGAngle a);


#pragma mark UIEdgeInsets

/**
 Creates an edge inset.
 */
CG_INLINE UIEdgeInsets UIEdgeInsetsMakeWithSameMargin(CGFloat margin) {
    return (UIEdgeInsets){ .top = margin, .left = margin, .bottom = margin, .right = margin };
}

/**
 Creats an reverse inset.
 */
CG_INLINE UIEdgeInsets UIEdgeInsetsReverse(UIEdgeInsets insets) {
    return (UIEdgeInsets){ .top = -insets.top, .left = -insets.left, .bottom = -insets.bottom, .right = -insets.right };
}