iPhone animations - Moving a view in a circle
Is there a way to move a view around a center point without开发者_Go百科 rotating it using the view animations?
A A C A A
#import <QuartzCore/QuartzCore.h>
#define degreesToRadians(deg) (deg / 180.0 * M_PI)
manualy :
-(CGPoint)setPointToAngle:(int)angle center:(CGPoint)centerPoint radius:(double)radius
{
return CGPointMake(radius*cos(degreesToRadians(angle)) + centerPoint.x, radius*sin(degreesToRadians(angle)) + centerPoint.y);
}
with animation something like this:
int angle = 0; // start angle position 0-360 deg
CGPoint center = self.view.center;
CGPoint start = [self setPointToAngle:angle center:center radius:radius]; //point for start moving
CGMutablePathRef path = CGPathCreateMutable();
CGPathMoveToPoint(path, NULL, start.x, start.y);
for(int a =0;a<4;a++) //set path points for 90, 180, 270,360 deg form begining angle
{
angle+=45;
expPoint = [self setPointToAngle:angle center:center radius:expRadius];
angle+=45;
start = [self setPointToAngle:angle center:center radius:radius];
CGPathAddQuadCurveToPoint(path, NULL,expPoint.x, expPoint.y, start.x, start.y);
}
CAKeyframeAnimation *pathAnimation = [CAKeyframeAnimation animationWithKeyPath:@"position"];
pathAnimation.removedOnCompletion = NO;
pathAnimation.path = path;
[pathAnimation setCalculationMode:kCAAnimationCubic];
[pathAnimation setFillMode:kCAFillModeForwards];
pathAnimation.duration = 14.0;
[MY_VIEW.layer addAnimation:pathAnimation forKey:nil];
also look at
CGPathAddQuadCurveToPoint,
CGPathAddCurveToPoint,
CGPathAddArcToPoint,
CGPathAddArc
and others
Its not that big a deal to put an animation thread in and move it manually every frame so thats what I went with.
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