I have successfully implemented rotating a uiimageview using this code from this post
iPhone - Wheel tracking finger jumps to same starting position?
My question to fellow developers is that the user on touch can rotate the image both clockwise and counterclockwise. Is there a way I can detect in which direction is the user moving the view?
Its important to me because I am making a clock app. I let users move the min hand form 0 min all the way to 60 min. When it reaches there I move the hour hand one up. But the user can spin the min hand counter clockwise in which case I need to move the hour hand one down. Any ideas?
you can set a member variable named "lastPoint" to record the point last time you moved
the you can calc the direction next time
CGPoint lastPoint;
- (void) touchedBegin:(NSSet *)touches withEvent:(UIEvent *)event {
lastPoint = [touch locationInView:self.view];
}
-(void) touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event {
NSSet *allTouches = [event allTouches];
//you can save the point , then used in next time you want
int tInput = [allTouches count]-1;
UITouch *touch =[[allTouches allObjects] objectAtIndex:tInput];
CGPoint location = [touch locationInView:self.view];
float theAngle = atan2( location.y-imageX.center.y, location.x-imageX.center.x );
float theLastAngle = atan2( lastPoint.y-imageX.center.y, lastPoint.x-imageX.center.x );
lastPoint = location;
// compare theAngle & theLastAngle , so you can know it is clockwise or counterclockwise.
}
Related
I an interested in trying to create a few games, namely in the new sprite kit. However, for the game that I have in mind I would rather use a directional pad vs a joy stick. Since I shall be moving over from Cocos, my old program no longer works (so neither will that dpad). Sadly, I have not come accross any tutorial that may help with implementing one in the new sprite kit (only joy sticks). I was wondering and hoping if anyone came across a simple dpad class from github or something or a helpful link that they would like to share. Thanks
Here's one way:
//Joystick node
- (SKSpriteNode *)controlPadNode
{
SKSpriteNode *controlPadNode = [SKSpriteNode spriteNodeWithImageNamed:#"game-controller-front"];
controlPadNode.position = CGPointMake(controlPadX,controlPadY);
controlPadNode.name = #"controlPadNode";
controlPadNode.zPosition = 1.0;
return controlPadNode;
}
//handle touch events
- (void)touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
UITouch *touch = [touches anyObject];
CGPoint location = [touch locationInNode:self];
SKNode *node = [self nodeAtPoint:location];
//if control pad touched
if ([node.name isEqualToString:#"controlPadNode"]) {
touchX = location.x;
touchY = location.y;
controlButtonDown = true;
}
}
//when touch moves
- (void) touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event {
UITouch *touch = [touches anyObject];
CGPoint location = [touch locationInNode:self];
SKNode *node = [self nodeAtPoint:location];
//if control pad touched
if ([node.name isEqualToString:#"controlPadNode"]) {
touchX = location.x;
touchY = location.y;
controlButtonDown = true;
}
}
- (void) touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event {
UITouch *touch = [touches anyObject];
CGPoint location = [touch locationInNode:self];
SKNode *node = [self nodeAtPoint:location];
//if control pad touched
if ([node.name isEqualToString:#"controlPadNode"]) {
controlButtonDown = false;
}
}
//update method
-(void)update:(NSTimeInterval)currentTime {
if (controlButtonDown) {
//the control pad
SKNode *controlNode = [self childNodeWithName:#"controlPadNode"];
//the node you want to move
SKNode *node = [self childNodeWithName:#"spaceShipNode"];
//compute the angle between parameters pad and the horizontal
float angle = atan2f (touchY - controlPadY, touchX - controlPadX) ;
//move the control pad for the player to have a sense of movement
SKAction *moveControlPad = [SKAction moveTo:CGPointMake(touchX, touchY) duration:0.00001];
double distance = sqrt(pow((touchX - controlPadX), 2.0) + pow((touchY - controlPadY), 2.0));
//make sure the control pad only moves 40 pixels
if( distance < 40 ){
[controlNode runAction:moveControlPad];
}
//move the ship
SKAction *moveShip = [SKAction moveByX: 6*cosf(angle) y:6*sinf(angle) duration:0.005];
[node runAction: moveShip];
}
}
EDIT:
Also can use this to move the control pad back when touch ends:
if (!controlButtonDown) {
SKNode *controlNode = [self childNodeWithName:#"controlPadNode"];
SKAction *moveControlPad = [SKAction moveTo:CGPointMake(controlPadX, controlPadY) duration:0.00001];
[controlNode runAction:moveControlPad];
}
I've built a small UIKit based game engine before the introduction of SpriteKit. My engine loads cocos2d compatible maps from Tiled, sprites from TexturePacker, and it comes with a joystick that I ported from cocos2d to UIKit. (Mine is based on sneaky-joystick.)
You can grab the whole library on GitHub and pull out the parts you need. It's fairly modular.
I am super frustrated and I know it is just because I don't know what i am doing with cocos2d. I am following Ray Wenderlich tutorials on cocos2d and I am trying to put it all together. When the screen is tapped,one bullet is fired in the direction of the tap. I am using
- (void)ccTouchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
UITouch *touch = [touches anyObject];
CGPoint touchLocation = [self convertTouchToNodeSpace:touch];
[self.officer shootToward:touchLocation];
[self.officer shootNow];
}
- (void)ccTouchesMoved:(NSSet *)touches withEvent:(UIEvent *)event {
UITouch *touch = [touches anyObject];
CGPoint touchLocation = [self convertTouchToNodeSpace:touch];
[self.officer shootToward:touchLocation];
[self.officer shootNow];
}
which calls these methods in my Officer class
- (void)shootNow {
// 1
CGFloat angle = ccpToAngle(_shootVector);
_gun.rotation = (-1 * CC_RADIANS_TO_DEGREES(angle)) + 90;
// 2
CGSize winSize = [[CCDirector sharedDirector] winSize];
float mapMax = MAX(winSize.width, winSize.height);
CGPoint actualVector = ccpMult(_shootVector, mapMax);
// 3
float POINTS_PER_SECOND = 300;
float duration = mapMax / POINTS_PER_SECOND;
// 5
for(id item in self.children) {
NSString *bulletName = [NSString stringWithFormat:#"bullet.png"];
CCSprite * bullet = [CCSprite spriteWithSpriteFrameName:bulletName];
//bullet.tag = _type;
bullet.position = ccpAdd(self.position, ccpMult(_shootVector, _gun.contentSize.height));
CCMoveBy * move = [CCMoveBy actionWithDuration:duration position:actualVector];
CCCallBlockN * call = [CCCallBlockN actionWithBlock:^(CCNode *node) {
[node removeFromParentAndCleanup:YES];
}];
[bullet runAction:[CCSequence actions:move, call, nil]];
[self.batchNode addChild:bullet];
//[self addChild:bullet];
[_shotsFired addObject:bullet];
}
}
So I figured it would be a simple for loop go through the 5th step x amount of times then call a reload method. Well that didn't work. So I tried to count the touches on the screen, I figured if I got x amount of taps then call the reload method(which is not written yet)? The problem with that was every time you pressed a different area of the screen the count started over from one. Some please help me through this week long process of pulling my hair out? How do I count the amount of times I have fired the gun?
Couldn't you just make a property on your view controller and then every time the shoot now method is called just add 1 to your property, then reset it to 0 when you call the reload method?
I'm having a problem with a jumping movement with using CGAffineTransformMakeRotation. It seems to work fine until I get to the top of quadrants 1 and 2. Below is the code I am using and youtube link that shows what happens. Any insight would be really appreciated.
My goal is to rotate a UIWebView with an svg inside. Since I can't easily detect touch on the UIWebView alone, I'm putting a blank UIImageView over it. This allows me to detect the touch and prevent the copy dialog from popping up.
http://www.youtube.com/watch?v=x_OmS0MPdEE&feature=youtu.be
- (void)touchesMoved: (NSSet *)touches withEvent:(UIEvent *)event {
[super touchesBegan:touches withEvent:event];
NSArray *allTouches = [touches allObjects];
CGPoint location = [[allTouches objectAtIndex:0] locationInView:self.view];
if(selected == 1) {
CGFloat rads = atan2f(location.y - (grid1.frame.size.height/2),location.x - (grid1.frame.size.width/2));
grid1.transform = grid1Btn.transform = CGAffineTransformMakeRotation(rads);
}
}
- (void) touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event {
[super touchesBegan:touches withEvent:event];
NSArray *allTouches = [touches allObjects];
CGPoint location = [[allTouches objectAtIndex:0] locationInView:self.view];
if(CGRectContainsPoint(grid1Btn.frame, location))
{
selected = 1;
}
}
- (void)touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event
{
selected = -1;
}
You use some frame.size.* in your computations. Note, that those values (unlike bounds.size.*) are affected by transform. Use grid1.center instead. It is also more logical (you rotate around center).
The next thing you need to fix is that it should not jump to new position when touches start :)
The jerkiness is caused by the inherent inaccuracy of touch event locations.
Touch events that are located sufficiently close to the center of the frame have a high likelihood of straying to the diagonally opposite quadrant of the frame whilst a circle is being traced about the center of the frame.
This will result in a sudden jump of 90 degrees as observed in your video.
One way to avoid the problem is to introduce a dead zone about the center of the frame. Any touch that is located within a given radius of the center of the frame would not trigger the rotation to be recalculated.
Hope this helps.
I have a view control and inside I plan to place some controls like buttons textbox etc... I can drag my view along the x axis like:
1)
2)
with the following code:
-(void) touchesBegan:(NSSet *)touches withEvent:(UIEvent *)event
{
UITouch *touch = [[event allTouches] anyObject];
if( [touch view] == ViewMain)
{
CGPoint location = [touch locationInView:self.view];
displaceX = location.x - ViewMain.center.x;
displaceY = ViewMain.center.y;
startPosX = location.x - displaceX;
}
CurrentTime = [[NSDate date] timeIntervalSince1970];
}
- (void) touchesMoved:(NSSet *)touches withEvent:(UIEvent *)event{
UITouch *touch = [[event allTouches] anyObject];
if( [touch view] == ViewMain)
{
CGPoint location = [touch locationInView:self.view];
location.x =location.x - displaceX;
location.y = displaceY;
ViewMain.center = location;
}
}
-(void) touchesEnded:(NSSet *)touches withEvent:(UIEvent *)event{
double time = [[NSDate date] timeIntervalSince1970]-CurrentTime;
UITouch *touch = [[event allTouches] anyObject];
if( [touch view] == ViewMain)
{
CGPoint location = [touch locationInView:self.view];
location.x =location.x - displaceX;
location.y = displaceY;
ViewMain.center = location;
double speed = (ViewMain.center.x-startPosX)/(time*2);
NSLog(#"speed: %f", speed);
}
}
not that I have to add the global variables:
float displaceX = 0;
float displaceY = 0;
float startPosX = 0;
float startPosY = 0;
double CurrentTime;
the reason why I created those variables is so that when I start dragging the view the view moves from the point where I touch it instead of from the middle.
Anyways if I touch a button or image the view will not drag even though the images have transparency on the background. I want to be able to still be able to drag the view regardless if there is an image on top of the view. I where thinking that maybe I need to place a large transparent view on top of everything but I need to have buttons, images etc. I want to be able to drag a view just like you can with:
note that I was able to drag the view regardless of wither I first touched an app/image or text. How could I do that?
I think your problem is that if you touch a UIButton or a UIImageView with interaction enabled, it doesn't pass the touch along.
For the images, uncheck the User Interaction Enabledproperty in IB.
For the buttons that are causing touchesBegan:withEvent:, etc. to not get called, then look at the following link: Is there a way to pass touches through on the iPhone?.
You may want to consider a different approach to this problem. Rather than trying to manually manage the content scrolling yourself you would probably be better off using a UIScrollView with the pagingEnabled property set to YES. This is the method Apple recommends (and it's probably the method used by Springboard.app in your last screenshot). If you are a member of the iOS developer program check out the WWDC 2010 session on UIScrollView for an example of this. I think they may have also posted sample code on developer.apple.com.
I am trying to use both b2PrismaticJoint and b2MouseJoint. I need to move my projectile along x-axis to position it for target and want to only swipe vertically without moving the projectile to throw it in that direction. I am using ApplyLinearImpulse() but no matter in which direction i swipe it's direction is always towards top-right. The code is:
- (void)ccTouchesEnded:(NSSet *)touches withEvent:(UIEvent *)event {
UITouch *myTouch = [touches anyObject];
CGPoint location = [myTouch locationInView:[myTouch view]];
location = [[CCDirector sharedDirector] convertToGL:location];
b2Vec2 locationWorld = b2Vec2(location.x/PTM_RATIO, location.y/PTM_RATIO);
if (_mouseJoint) {
_world->DestroyJoint(_mouseJoint);
_mouseJoint = NULL;
}
if(_primJoint) {
_world->DestroyJoint(_primJoint);
_primJoint = NULL;
}
if (hit) {
_strikerBody->ApplyLinearImpulse(locationWorld, _strikerBody->GetPosition());
}
}
Looks like your locationWorld vector is pointing in the same direction every time. I think you want something like this:
b2Vec2 impulseDirection = locationWorld - _strikerBody->GetPosition();
impulseDirection.Normalize();
const double Force = 10 * _strikerBody->GetMass(); //or anything you want
_strikerBody->ApplyLinearImpulse( Force*impulseDirection, _strikerBody->GetPosition() );
Now the impulse will be applied to the center of the _strikerBody in the touch direction (relative to the _strikerBody) .