Can anyone help convert this this actionscript to Objective-c?
if(mcMain.y >= stage.stageHeight - mcMain.height)
{
mainJumping = false;
mcMain.y = stage.stageHeight - mcMain.height;
}
Specifically the stage.stageHeight and mcMain.height?
Without knowing what mcMain and stage are, no, not easily. I assume that stage refers to the main drawing area; assuming that you are drawing within a UIView subclass, you can find the dimensions of the view by calling bounds upon the view:
CGRect bounds = self.bounds;
This will return a CGRect, which in itself is comprised of a CGPoint, called origin, and a CGSize called size; these are C-structs:
struct CGPoint {
CGFloat x;
CGFloat y;
};
struct CGSize {
CGFloat width;
CGFloat height;
};
To find the height of the UIView, you can do so quite simply:
CGFloat height = self.bounds.size.height;
Assuming that you are trying to find out the height of the view from within the view class itself.
I'm guessing that mcMain refers to some kind of image or object, so implementation of that is dependent on what it is. However, most co-ordinates rely on CGRect, CGPoint and CGSize in some way or another.
If you're coming from the Flash world(like I did), then I highly recommend looking into the open source Cocos2D-iPhone framework: http://www.cocos2d-iphone.org/
I've rewritten your code in approximate Objective-C, just to give you an idea of what it might look like.
float stageHeight = [UIScreen mainScreen].bounds.size.height;
float guyHeight = mainGuy.contentSize.height;
if(mainGuy.position.y >= stageHeight - guyHeight)
{
mainJumping = NO;
mainGuy.position = ccp(mainguy.position.x, stageHeight-guyHeight);
}
Related
I am working on a Coverflow style layout for UICollectionView. Its a simple enough concept, and just to make it easier there are about 100 tutorials on the subject. However as anyone doing transforms knows, m34 is the magic number. However, as soon as I set it to get some perspective for my rotations, the views disappear. The only appear when the rotation is near 0.
I suspect this is a bounds/zIndex issue, however after days of monkeying around with zIndexes and clipping adjustments, the cells just refuse to appear. Any help is greatly appreciated.
- (NSArray *)layoutAttributesForElementsInRect:(CGRect)rect
{
NSArray *array = [super layoutAttributesForElementsInRect:rect];
CGRect visibleRect = (CGRect){self.collectionView.contentOffset, self.collectionView.bounds.size};
CGFloat maxDistance = visibleRect.size.width / 2.0;
CGFloat maxRotation = M_PI_2;
[array enumerateObjectsUsingBlock:^(UICollectionViewLayoutAttributes * attributes, NSUInteger idx, BOOL *stop) {
CGFloat distanceFromCenter = CGRectGetMidX(visibleRect) - attributes.center.x;
CGFloat percentageFromCenter = distanceFromCenter / maxDistance;
percentageFromCenter = MIN(percentageFromCenter, 1.0);
percentageFromCenter = MAX(percentageFromCenter, -1.0);
CGFloat angle = percentageFromCenter * maxRotation;
CATransform3D transform = CATransform3DIdentity;
// transform.m34 = 1.0 / -800.0;
transform = CATransform3DRotate(transform, angle, 0.0, 1.0, 0.0);
attributes.transform3D = transform;
}];
return array;
}
So thanks to one #mpospese on Twitter. The problem wasn't with the m34 value itself. It was with a particular feature of UICollectionView.
when frame height exceeds collection view’s height, cells are removed
So in my case I had a UICollectionViewLayout specially designed to grab the height of the UICollectionView and use it for the height of the cells. Problem is, when m34 is factored in that obviously adjusts the frame and therefore exceeds the bounds. Rather than just clipping the cell like most UIView operations would have done pointing directly to the problem, UICollectionView actually automatically removes cells entirely if they so much as brush the outer-bounds.
So I have a UIView called fallingBall that currently collides nicely with my UIView called theBlockView. I am using CGRectIntersectsRect(theBlockView.frame, fallingBall.frame) to detect this collision.
That's all very well, so now I would like my fallingBall to actually be round, and I would also like the top corners of theBlockView to be rounded. To do this, I used the following code:
//round top right-hand corner of theBlockView
UIBezierPath *maskPath = [UIBezierPath bezierPathWithRoundedRect:theBlockView.bounds
byRoundingCorners:UIRectCornerTopRight
cornerRadii:CGSizeMake(10.0, 10.0)];
CAShapeLayer *maskLayer = [CAShapeLayer layer];
maskLayer.frame = theBlockView.bounds;
maskLayer.path = maskPath.CGPath;
theBlockView.layer.mask = maskLayer;
//round the fallingBall view
[[fallingBall layer] setCornerRadius:30];
But, funnily enough, though they look nice and rounded, the views are still rectangles.
So my question is: how can I make CGRectIntersectsRect treat them as the shapes that they look like? Is there a function that works the same but uses the view's alpha to detect collisions?
Thanks for your time!
Actually, let me answer my own question!
OK, so I spent the greater part of the last 10 hours looking around, and I came across this post: Circle-Rectangle collision detection (intersection) - check out what e.James has to say!
I wrote a function to help with this: first, declare the following structs:
typedef struct
{
CGFloat x; //center.x
CGFloat y; //center.y
CGFloat r; //radius
} Circle;
typedef struct
{
CGFloat x; //center.x
CGFloat y; //center.y
CGFloat width;
CGFloat height;
} MCRect;
Then add the following function:
-(BOOL)circle:(Circle)circle intersectsRect:(MCRect)rect
{
CGPoint circleDistance = CGPointMake(abs(circle.x - rect.x), abs(circle.y - rect.y) );
if (circleDistance.x > (rect.width/2 + circle.r)) { return false; }
if (circleDistance.y > (rect.height/2 + circle.r)) { return false; }
if (circleDistance.x <= (rect.width/2)) { return true; }
if (circleDistance.y <= (rect.height/2)) { return true; }
CGFloat cornerDistance_sq = pow((circleDistance.x - rect.width/2), 2) + pow((circleDistance.y - rect.height/2), 2);
return (cornerDistance_sq <= (pow(circle.r, 2)));
}
I hope this helps someone!
CGRectIntersectsRect will always use rectangles, also the frames of the views will always be rectangles. You will have to write your own function. You could use the center of your views to calculate circles using the corner radius, and test if the rectangles AND the circles intersect somehow.
I'm pretty sure this is more a of a math question, but I'll phrase it in the context of UIView and iPad-related objective C
I am importing raw data from a mapping file I have created from some public domain material downloaded elsewhere, then split out to isolate various regions within the map. Each region has a number of sub-regions, much like, for example, the continental US and then the various states which appear within the US, and then each sub-region is broken down again, into, let's say, counties.
Each state, and each county has a bounding box which tells me the origin, the width, and height each is.
In my initial setup, I created a separate view for each state, and then another view for each county. The polygon representing the area of the state/county was rendered (obviously with the county on top of the state so it would be visible) relative to a view I created through interface builder, called mainContainerView. This initial setup worked correctly.
Now I am trying to change things a bit, by adding the counties to the UIView holding the polygon for the state, so I will be able to overlay the state as a clipping mask on the counties. The problem is that no matter what I try, I cannot seem to get the county to translate to the right place within the state's view.
It seems like it should be straightforward addition or subtraction as the scaling for each item is exactly the same, and I'm not trying to do any major transformations, so I do not believe the CFAffineTransformation family is needed.
I can post code if necessary, but I'm not trying to get someone to write my program for me; I just want someone to point me in the right direction here, by giving me a suggestion on how to set the county relative to the state within the state's view.
As per a request, here's the relevant code that I am working on right now. This code does not work, but it gives you the idea as to what I'm doing. Posting sample data is a little more difficult, as it involves arrays of points and data extracted from a .SHP file designed to produce a map (and subdivisions). I'll include some comments in the code with some real point values as I step through the program to show you what's happening to them.
MASK_MAX_EASTING, MASK_MAX_NORTHING, MASK_MIN_EASTING, and MASK_MIN_NORTHING are constants which define the bounding box for the entire map of the country when made up of states.
DIST_MAX_EASTING, DIST_MAX_NORTHING, DIST_MIN_EASTING, and DIST_MIN_NORTHING are constants which define the bounding box for a map of the country when made up of the counties. The scales of the two maps are slightly different, so, by using the different bounding boxes, I've been able to scale the two maps to the same size.
-(void)didLoadMap:(NSNotification *)notification {
id region = [notification object];
ShapePolyline *polygon = [region polygon];
if ([notification name] == #"MapsLoadingForState") {
// m_nBoundingBox is an array which contains the RAW northing and easting values for each subdivision. [0] - west limit, [1] - south limit, [2] - east limit, [3] - north limit.
// The code below, combined with the drawrect method in DrawMap.m (below) puts all the states on the map in precisely the right places, so for the state maps, it works just fine.
CGFloat originX = ((polygon->m_nBoundingBox[0]-MASK_MIN_EASTING)*stateScaleMultiplier)+([mainContainerView frame].size.width/2);
CGFloat originY = ((MASK_MAX_NORTHING-(polygon->m_nBoundingBox[3]))*stateScaleMultiplier)+[mainContainerView frame].origin.y;
CGFloat width = polygon->m_nBoundingBox[2] - polygon->m_nBoundingBox[0];
CGFloat height = polygon->m_nBoundingBox[3] - polygon->m_nBoundingBox[1];
CGFloat scaledWidth = width*stateScaleMultiplier;
CGFloat scaledHeight = height*stateScaleMultiplier;
UIColor *subViewColor = [UIColor colorWithRed:0.0 green:1.0 blue:1.0 alpha:0.0];
stateMapView = [[DrawMap alloc] initWithFrame:CGRectMake(originX, originY, scaledWidth, scaledHeight)];
[stateMapView setBackgroundColor:subViewColor];
[stateMapView setStateScale:stateScaleMultiplier];
[stateMapView setCountyScale:countyScaleMultiplier]; // Not actually needed.
[stateMapView setClippingMask:polygon];
UIColor *colorMask = [UIColor colorWithWhite:1.0 alpha:1.0];
[stateMapView setForeground:colorMask];
[states addObject:stateMapView]; // Add the state map view to an array (for future use)
[mapView addSubview:stateMapView]; // MapView is a UIView of equivalent size and shape as mainContainerView.
} else {
// This is where the problems occur.
CGFloat originX = (polygon->m_nBoundingBox[0]-DIST_MIN_EASTING); // 4431590 (raw data)
originX *= countyScaleMultiplier; // 303.929108
originX += ([mainContainerView frame].size.width/2); // 815.929077
CGFloat originY = (DIST_MAX_NORTHING-polygon->m_nBoundingBox[3]); 4328997
originY *= countyScaleMultiplier; // 296.893036
originY -= [mainContainerView frame].origin.y; // 340.893036
CGRect frame = [stateMapView frame]; // Dummy variable created for watches in the debugger. x=856.237183, y=332.169922 width=34.3800087, height=28.7534008
// When I was invoking DrawMap.h and the included drawrect method, the county map would easily be displayed in the right place, as you can see by the values above.
// This is where I think the problem is. The X value is WAY off as far as I can tell.
originX -= frame.origin.x; // -40.3081055
originY -= frame.origin.y; // 8.72311401
CGPoint countyOrigin = CGPointMake(originX,originY);
// Translate the county's origin so it is relative to the origin of stateMapView, not MainContainerView (doesn't work)
[stateMapView addCountyMap:[region polygon] withColor:winner translatedBy:countyOrigin];
[stateMapView setNeedsDisplay];
}
I am aware that there are several issues with this code and some stuff outside the scope of this question may make a few of you raise an eyebrow (or two) but this is definitely a work in progress...
Here's the relevant code from DrawMap.m; I've cut a bunch of stuff out because it is extraneous.
- (void)drawRect:(CGRect)rect {
// Set up
for (int i=0;i<[countyMaps count];i++) {
// Draw the polygon.
[[countyColors objectAtIndex:i] setFill];
[self drawPolygon:[countyMaps objectAtIndex:i]
usingScale:stateScale
translatedBy:CGPointMake([[countyTranslations objectAtIndex:2*i] floatValue],
[[countyTranslations objectAtIndex:2*i+1] floatValue])];
}
// Set the blend mode to multiply
CGContextSetBlendMode(context, kCGBlendModeMultiply);
// Draw a path with clippingMask
[[UIColor colorWithWhite:1.0 alpha:1.0] setFill];
// CGPoint translate = CGPointMake(0,0);
[self drawPolygon:clippingMask usingScale:stateScale translatedBy:CGPointMake(0,0)];
}
-(void)drawPolygon:(ShapePolyline *)aPolygon usingScale:(float)mapScale translatedBy:(CGPoint)trans {
for (int j=0;j<[aPolygon numParts];j++) {
UIBezierPath *path = [UIBezierPath bezierPath];
[path setLineJoinStyle:kCGLineJoinRound];
int startIndex = [[[aPolygon m_Parts] objectAtIndex:j] intValue];
int endIndex = [aPolygon numPoints];
CGPoint startPoint;
[[[aPolygon m_Points] objectAtIndex:startIndex] getValue:&startPoint];
startPoint.x *=mapScale;
startPoint.y *=mapScale;
startPoint.x -= trans.x;
startPoint.y -= trans.y;
[path moveToPoint:startPoint];
if (j+1 != [aPolygon numParts]){
endIndex = [[[aPolygon m_Parts] objectAtIndex:j+1] intValue];
}
for (int k=startIndex+1; k<endIndex; k++)
{
CGPoint nextPoint;
[[[aPolygon m_Points] objectAtIndex:k] getValue:&nextPoint];
nextPoint.x *= mapScale;
nextPoint.y *= mapScale;
nextPoint.x -= trans.x;
nextPoint.y -= trans.y;
[path addLineToPoint:nextPoint];
}
[path closePath];
// [path stroke];
[path fill];
}
}
This tome is really may be too much information, or it may not be enough. Either way, hopefully by adding code, I've given you some information to go on...
-SOLVED-
And it was so simple. I'm surprised it took me this long to figure it out, as I was right in my initial question - it was simple addition and subtraction:
All translations are now done inside the methods which render the polygons. For each point in the polygon, I needed to add the origin of the state's view, and subtract the origin of the county's bounding box, then subtract 44 from the Y-value (the height of the control bar).
This, I think, is an example of over-thinking a problem, getting frustrated, over-thinking more, only to find out three days later that the answer is staring you in the face, waving a red flag, and shouting, "I'M OVER HERE!!!!"
I am trying to create a higher resolution image of a UIView, specifically UITextView.
This question and answer is exactly what I am trying to figure out:
Retain the resolution of the label after scaling in iphone
But, when I do the same, my text is still blurry:
self.view.transform = CGAffineTransformMakeScale(2.f, 2.f);
[myText setContentScaleFactor:2.f]; // myText is a subview of self.view object
I have also tried the same in the Apple sample project "UICatalog" to UILabel and it is also blurry.
I can't understand why it would work for Warrior from the other question and not for me. I would have asked there — but I can't seem to leave a comment or a question there.
Setting the contentScaleFactor and contentsScale is in fact the key, as #dbotha pointed out, however you have to walk the view and layer hierarchies separately in order to reach every internal CATiledLayer that actually does the text rendering. Adding the screen scale might also make sense.
So the correct implementation would be something like this:
- (void)updateForZoomScale:(CGFloat)zoomScale {
CGFloat screenAndZoomScale = zoomScale * [UIScreen mainScreen].scale;
// Walk the layer and view hierarchies separately. We need to reach all tiled layers.
[self applyScale:(zoomScale * [UIScreen mainScreen].scale) toView:self.textView];
[self applyScale:(zoomScale * [UIScreen mainScreen].scale) toLayer:self.textView.layer];
}
- (void)applyScale:(CGFloat)scale toView:(UIView *)view {
view.contentScaleFactor = scale;
for (UIView *subview in view.subviews) {
[self applyScale:scale toView:subview];
}
}
- (void)applyScale:(CGFloat)scale toLayer:(CALayer *)layer {
layer.contentsScale = scale;
for (CALayer *sublayer in layer.sublayers) {
[self applyScale:scale toLayer:sublayer];
}
}
UITextView has textInputView property, which "both draws the text and provides a coordinate system" (https://developer.apple.com/reference/uikit/uitextinput/1614564-textinputview)
So i'm using the following code to scale UITextView - without any font changes, without using any "CALayer" property and keeping high quality:
float screenScaleFactor = [[UIScreen mainScreen] scale];
float scale = 5.0;
textView.transform = CGAffineTransformMakeScale(scale, scale);
textView.textInputView.contentScaleFactor = screenScaleFactor * scale;
Comment the last line if you need low quality (but better performance) scaling.
Transform uses view.center as scaling center point, so adding a 'translate transform' is needed to scale around view corner.
Be sure to apply the contentScaleFactor to all subviews of the UITextView. I've just tested the following with a UITextView and found it to work:
- (void)applyScale:(CGFloat)scale toView:(UIView *)view {
view.contentScaleFactor = scale;
view.layer.contentsScale = scale;
for (UIView *subview in view.subviews) {
[self applyScale:scale toView:subview];
}
}
I'm trying to get an effect like the zoomRectToVisible-method of UIScrollview.
But my method should be able to center the particular rect in the layer while zooming and it should be able to re-adjust after the device orientation changed.
I'm trying to write a software like the marvel-comic app and need a view that presents each panel in a page.
For my implementation I'm using CALayer and Core Animation to get the desired effect with CATransform3D-transformations. My problem is, I'm not able to get the zoomed rect/panel centered.
the structure of my implementation looks like this: I have a subclass of UIScrollview with a UIView added as subview. The UIView contains the image/page in it's CALayer.contents and I use core animations to get the zooming and centering effect. The zoom effect on each panel works correcty but the centering is off. I'm not able to compute the correct translate-transformation for centering.
My code for the implementation of the effect is like this:
- (void) zoomToRect:(CGRect)rect animated:(BOOL)animated {
CGSize scrollViewSize = self.bounds.size;
// get the current panel boundingbox
CGRect panelboundingBox = CGPathGetBoundingBox([comicPage panelAtIndex:currentPanel]);
// compute zoomfactor depending on the longer dimension of the panelboundingBox size
CGFloat zoomFactor = (panelboundingBox.size.height > panelboundingBox.size.width) ? scrollViewSize.height/panelboundingBox.size.height : scrollViewSize.width/panelboundingBox.size.width;
CGFloat translateX = scrollViewSize.width/2 - (panelboundingBox.origin.x/2 + panelboundingBox.size.width/2);
CGFloat translateY = scrollViewSize.height/2 - (panelboundingBox.size.height/2 - panelboundingBox.origin.y);
// move anchorPoint to panelboundingBox center
CGPoint anchor = CGPointMake(1/contentViewLayer.bounds.size.width * (panelboundingBox.origin.x + panelboundingBox.size.width/2), 1/contentViewLayer.bounds.size.height * (contentViewLayer.bounds.size.height - (panelboundingBox.origin.y + panelboundingBox.size.height/2)));
// create the nessesary transformations
CATransform3D translateMatrix = CATransform3DMakeTranslation(translateX, -translateY, 1);
CATransform3D scaleMatrix = CATransform3DMakeScale(zoomFactor, zoomFactor, 1);
// create respective core animation for transformation
CABasicAnimation *zoomAnimation = [CABasicAnimation animationWithKeyPath:#"transform"];
zoomAnimation.fromValue = (id) [NSValue valueWithCATransform3D:contentViewLayer.transform];
zoomAnimation.toValue = (id) [NSValue valueWithCATransform3D:CATransform3DConcat(scaleMatrix, translateMatrix)];
zoomAnimation.removedOnCompletion = YES;
zoomAnimation.duration = duration;
// create respective core animation for anchorpoint movement
CABasicAnimation *anchorAnimatione = [CABasicAnimation animationWithKeyPath:#"anchorPoint"];
anchorAnimatione.fromValue = (id)[NSValue valueWithCGPoint:contentViewLayer.anchorPoint];
anchorAnimatione.toValue = (id) [NSValue valueWithCGPoint:anchor];
anchorAnimatione.removedOnCompletion = YES;
anchorAnimatione.duration = duration;
// put them into an animation group
CAAnimationGroup *group = [CAAnimationGroup animation];
group.animations = [NSArray arrayWithObjects:zoomAnimation, anchorAnimatione, nil] ;
/////////////
NSLog(#"scrollViewBounds (w = %f, h = %f)", self.frame.size.width, self.frame.size.height);
NSLog(#"panelBounds (x = %f, y = %f, w = %f, h = %f)", panelboundingBox.origin.x, panelboundingBox.origin.y, panelboundingBox.size.width, panelboundingBox.size.height);
NSLog(#"zoomfactor: %f", zoomFactor);
NSLog(#"translateX: %f, translateY: %f", translateX, translateY);
NSLog(#"anchorPoint (x = %f, y = %f)", anchor.x, anchor.y);
/////////////
// add animation group to layer
[contentViewLayer addAnimation:group forKey:#"zoomAnimation"];
// trigger respective animations
contentViewLayer.anchorPoint = anchor;
contentViewLayer.transform = CATransform3DConcat(scaleMatrix, translateMatrix);
}
So the view requires the following points:
it should be able to zoom and center a rect/panel of the layer/view depending on the current device orientation. (zoomRectToVisible of UIScrollview does not center the rect)
if nessesary (either device orientation changed or panel requires rotation) the zoomed panel/rect should be able to rotate
the duration of the animation is depending on user preference. (I don't know whether I can change the default animation duration of zoomRectToVisible of UIScrollView ?)
Those points are the reason why I overwrite the zoomRectToVisible-method of UIScrollView.
So I have to know how I can correctly compute the translation parameters for the transformation.
I hope someone can guide me to get the correct parameters.
Just skimmed over your code and this line is probably not being calculated as you think:
CGPoint anchor = CGPointMake(1/contentViewLayer.bounds.size.width * (panelboundingBox.origin.x + panelboundingBox.size.width/2), 1/contentViewLayer.bounds.size.height * (contentViewLayer.bounds.size.height - (panelboundingBox.origin.y + panelboundingBox.size.height/2)));
You're likely to get 0 because of the 1/ at the start. C will do your multiplication before this division, resulting in values <1 - probably not what you're after. See this
You might find it more useful to breakdown your calculation so you know it's working in the right order (just use some temporary variables) - believe me it will help enormously in making your code easier to read (and debug) later. Or you could just use more brackets...
Hope this helps.