I am trying to convert a double to radians using the Objective c function toRadians like this:
double oldLat = toRadians(oldLocation.coordinate.latitude);
but I keep getting a compiler warning and error or implicit declaration of toRadians and toDegrees
I included #import <math.h> but that didn't solve the problem for some reason.
any help would be greatly appreciated.
There is no toRadians in the Foundation classes. You can just convert it manually
degrees * M_PI / 180.0
Foundation imports math.h so you'll have M_PI otherwise you'll have to
#include <math.h>
try this coding:- ( radian to degree)
location = [[CCDirector sharedDirector] convertToGL:location];
// Determine offset of location to projectile
int offX = location.x - PROJECTILE_POSITION_X;
int offY = location.y - PROJECTILE_POSITION_Y;
int realX = winSize.width + (PROJECTILE_WIDTH/2);
float ratio = (float) offY / (float) offX;
int realY = (realX * ratio) + PROJECTILE_POSITION_Y;
int offRealX = realX - PROJECTILE_POSITION_X;
int offRealY = realY - PROJECTILE_POSITION_Y;
// Determine angle to face
float angleRadians = atanf((float)offRealY / (float)offRealX);
float angleDegrees = (__angleRadians__)/((__angleRadians__) * 57.29577951f);
Related
I m start learning game development. As a beginner i create one demo game in which one cannon hit bullets to the enemies (coming toward cannon from different direction).
Now i stuck on cannon sprite image rotation anywhere user touch on the screen or enemies. How i do that, My initial code as following,
void HelloWorld:: ccTouchesBegan(CCSet *touches, CCEvent * event)
{
CCSize winSize = CCDirector::sharedDirector()->getWinSize();
CCTouch* touch = (CCTouch*)( touches->anyObject() );
CCPoint location = touch->locationInView(touch->view());
location = CCDirector::sharedDirector()->convertToGL(location);
//Rotate cannon direction toward touch point
CCPoint diffPoint = ccpSub(_cannonImage->getPosition(), location);
float angleRadians = atanf((float)diffPoint.y/(float)diffPoint.x);
float angleOffset = CC_DEGREES_TO_RADIANS(180);
if(diffPoint.x < 0){
angleRadians += angleOffset;
}else{
angleRadians -= angleOffset;
}
CCLog("angle to be rotate = %f", angleRadians);
_cannonImage->runAction(CCRotateBy::actionWithDuration(0.1, angleRadians));
}
The code is written in cocos2d-x . I also accepting answer by someone who written in plain cocos2d.
Thanks
iHungry
The perfect answer as follows,
float HelloWorld::changingAngleAccordingToCoordinateSystem(CCPoint imageCenter, CCPoint touchLocation, float calculatedAngle){
//Consideration :- all Angles is in Degree
if((calculatedAngle >= 0 && calculatedAngle <= 90) || (calculatedAngle >= 90 && calculatedAngle <= 180)){
//Ist quardant
calculatedAngle = calculatedAngle;
}
else if(calculatedAngle < 0 && calculatedAngle >= -90){
//IInd quardant
calculatedAngle = 270 + (90 + calculatedAngle);
}
else if(calculatedAngle < -90 && calculatedAngle >= -180){
calculatedAngle = 180 + (180 + calculatedAngle);
}
return calculatedAngle;
}
//Rotate cannon direction toward touch point
float diff_X = touchLocation.x - myImage->getPosition().x;
float diff_Y = touchLocation.y - myImage->getPosition().y;
CCPoint diffPoint = CCPoint(diff_X, diff_Y);
float angleRadians = atan2f(diffPoint.y,diffPoint.x);
angleRadians = CC_RADIANS_TO_DEGREES(angleRadians);
angleRadians = HelloWorld::changingAngleAccordingToCoordinateSystem(myImage->getPosition(), touchLocation, angleRadians);
myImage->setRotation(-angleRadians);
i used this code to rotate my sprite. i Was moving the sprite according to my accelerometer reading.
float angleRadians =-accelX;
float angleDegrees = CC_RADIANS_TO_DEGREES(angleRadians);
objGlider->sprite_Glider.rotation = cocosAngle;
Check it. The reason of slow may be that you may be using CClog or NSLog in the code.
Here goes the complete code.
if(!boolPlayerDied)
{
static float prevX=0, prevY=0;
#define kFilterFactor 1.0f// don't use filter. the code is here just as an example
float accelX = (float) acceleration.x * kFilterFactor + (1- kFilterFactor)*prevX;
float accelY = (float) acceleration.y * kFilterFactor + (1- kFilterFactor)*prevY;
prevX = accelX;
prevY = accelY;
accelX = accelX-0.5;// Angle check fot tgfor the player to play
float angleRadians =-accelX;
float angleDegrees = CC_RADIANS_TO_DEGREES(angleRadians);
if(accelX>0)
{
cocosAngle = 1.1 * angleDegrees;
}
else
{
if(accelX<-0.5)
accelX=-0.5;
cocosAngle = 1.1 * angleDegrees;
}
objGlider->sprite_Glider.rotation = cocosAngle;
}
objGlider is the object of the class which creates glider sprite and sprite_Glider is the sprite used in glider class.
you can use rotation property with your sprite to be rotated. In cocos2Dx it might be setRotation.
First of all, replace
float angleRadians = atanf((float)diffPoint.y/(float)diffPoint.x);
float angleOffset = CC_DEGREES_TO_RADIANS(180);
if(diffPoint.x < 0){
angleRadians += angleOffset;
}else{
angleRadians -= angleOffset;
}
by
float angleRadians = atan2f(diffPoint.y, diffPoint.x);
Then it would be better to set rotation immediately (without actions) to process multiple frequent touches.
_cannonImage->setRotation(angleRadians);
Maybe you will need to adjust rotation like setRotation(-angleRadians) or setRotation(angleRadians+90) - it depends on your coordinate system.
i am following a tutorial on a simple cocos2d game.
however on that tutorial the bullets that the user fires is only on one direction
what can i do to make it fire on all directions not just one sided?
here is the code of the direction.
int offX = location.x - projectile.position.x;
int offY = location.y - projectile.position.y;
[self addChild:projectile];
int realX = winSize.width + (projectile.contentSize.width/2);
float ratio = (float) offY / (float) offX;
int realY = (realX *ratio) + projectile.position.y;
CGPoint realDest = ccp(realX, realY);
int offRealX = realX - projectile.position.x;
int offRealY = realY - projectile.position.y;
float length = sqrtf((offRealX*offRealX)+(offRealY*offRealY));
float velocity = 480/1;
float realMoveDuration = length/velocity;
[projectile runAction:[Sequence actions:[MoveTo actionWithDuration:realMoveDuration position:realDest],
[CallFuncN actionWithTarget:self selector:#selector(spriteMoveFinished:)], nil]];
all help will be greatly appreciated. Thanks
Assuming you are creating the projectile at the location of your character, you just need to figure out the direction before calculating the end point.
After adding the projectile:
[self addChild:projectile];
Add a scalar float:
float scalarX = 1.0f;
And make it negative if the touch is left of the character:
if (offX < 0.0f) scalar = -1.0f;
Then just multiply the realX by this scalar to make it point the correct way
int realX = scalar * (winSize.width + (projectile.contentSize.width/2));
float mcount=0;
mcount += 0.3;
CGAffineTransform transform = CGAffineTransformMakeRotation(mcount);
Clock.transform = transform;
i want GET Degree!
how to get rotation(degree) of this Object ? for exampke 90 degree.
i have Action Script 3 example :
myInt = clock_mc.rotation;
i need this method on Cocoa Touch
If I'm understanding your question correctly then a bit of mathematics can help here:
angleInRadians = angleInDegrees * M_PI / 180.0
To get the reverse, you reverse your equation. So first moving the division by 180 on the right to the left results in multiplying by 180.0
angleInRadians * 180.0 = angleInDegrees * M_PI
Now move the multiply by M_PI (the value of PI which is something like 3.1415962...) to the left, you reverse the operation:
(angleInRadians * 180.0) / M_PI = angleInDegrees
Now to make it nice for the program to use, we write it like so:
angleInDegrees = (angleInRadians * 180.0) / M_PI
So in your program, you could write your code like this:
var angleInDegrees = 0;
...
angleInDegrees = mcount * 180.0 / M_PI;
If you want to use a function then:
-(float) getAngleInDegrees:(float) radians
{
float angleInDegrees = 0;
angleInDegrees = radians * 180.0 / M_PI;
return angleInDegrees;
}
I think you want how to convert degrees into radians:-
for this you can use this formula:-
static inline double radians (double degrees) { return degrees * M_PI/180; }
UPDATED!
Do you want to get result rotation angle of Clock object?! If so, use this:
double rotationInRadians = atan2(Clock.transform.b, Clock.transform.a);
int rotationInDegrees = (int)round(rotationInRadians * 180 / M_PI);
Read this for details & explanation.
I am new in Box2D....
I have ball image in CCSprite. I want to move ball in whole screen using accelerometer...
tell me
How to use accelerometer in box2d??
Thanks...in advance
The standard cocos2d-box2d template file moves boxes using the accelerometer by applying gravity relative to the accelerometer value.
- (void)accelerometer:(UIAccelerometer*)accelerometer didAccelerate:(UIAcceleration*)acceleration
{
static float prevX=0, prevY=0;
//#define kFilterFactor 0.05f
#define kFilterFactor 1.0f // don't use filter. the code is here just as an example
float accelX = (float) acceleration.x * kFilterFactor + (1- kFilterFactor)*prevX;
float accelY = (float) acceleration.y * kFilterFactor + (1- kFilterFactor)*prevY;
prevX = accelX;
prevY = accelY;
// accelerometer values are in "Portrait" mode. Change them to Landscape left
// multiply the gravity by 10
b2Vec2 gravity( -accelY * 10, accelX * 10);
world->SetGravity( gravity );
}
You need to be more specific on what you want the ball to do dependent on how you move the phone. Your question is difficult to answer in its current form.
Get the accelerometer measurements and say Force = coefficient*measurements. The apply this force to your b2Body
Let your Ball Sprite having tag is 1.
Replace this code with your Accelerometer delegate,
I test it on device, its working.
and your ball will move with accelerometer.
-(void)accelerometer:(UIAccelerometer*)accelerometer didAccelerate:(UIAcceleration*)acceleration
{
#define kFilterFactor 0.75
accelerometer.updateInterval = 1.0f/60.0f;
static UIAccelerationValue rollingX = 0, rollingY = 0;
for (b2Body *b = world->GetBodyList(); b; b = b->GetNext())
{
if (b->GetUserData() != NULL)
{
CCSprite *sprite = (CCSprite*)b->GetUserData();
if (sprite.tag == 1) {
rollingX = (acceleration.x * kFilterFactor) + (rollingX * 0.25);
rollingY = (acceleration.y * kFilterFactor) + (rollingY * 0.25);
float accelX = rollingX;
float accelY = rollingY;
CGPoint moveNewPosition = sprite.position;
if (accelX > 0.1) {
moveNewPosition.y += 2;
} if (accelX < 0.1) {
moveNewPosition.y -= 2;
}
if (accelY > 0.1) {
moveNewPosition.x -= 2;
} if (accelY < -0.1) {
moveNewPosition.x += 2;
}
b->SetLinearVelocity(b2Vec2(2,2));
sprite.position = ccp(moveNewPosition.x , moveNewPosition.y );
sprite.rotation = -1 * CC_RADIANS_TO_DEGREES(b->GetAngle());
}
}
}
}
I hope it'll work.
I'm trying to rotate a sprite using the accelerometer. when I tilt right, I want him to rotate slightly to the right, and when I tilt left, I want him to rotate slightly to the left...
Thanks in advance,
Reed
Firs off - in your h file you need to make the following variables:
UIAccelerationValue accelerationX;
UIAccelerationValue accelerationY;
float currentRawReading;
float calibrationOffset;
Also ensure that your h file has:
#interface myViewName : UIViewController <UIAccelerometerDelegate>
Then in your .m file just below your imports at the top put:
#define kFilteringFactor 0.05
CGFloat DegreesToRadians(CGFloat degrees) {return degrees * M_PI / 180;};
CGFloat RadiansToDegrees(CGFloat radians) {return radians * 180/M_PI;};
Then in your .m file on your viewDidLoad Function put:
UIAccelerometer *accel = [UIAccelerometer sharedAccelerometer];
accel.delegate = self;
accel.updateInterval = 1.0f/60.0f;
also add the following function to your .m file:
-(void) accelerometer:(UIAccelerometer *)accelerometer didAccelerate:(UIAcceleration *)acceleration{
accelerationX = acceleration.x * kFilteringFactor + accelerationX * (1.0 - kFilteringFactor);
accelerationY = acceleration.y * kFilteringFactor + accelerationY * (1.0 - kFilteringFactor);
// keep the raw reading, to use during calibrations
currentRawReading = atan2(accelerationY, accelerationX);
float rotation = -RadiansToDegrees(currentRawReading);
targetView.transform = CGAffineTransformMakeRotation(-(DegreesToRadians(rotation)));
//targetView.transform = CGAffineTransformRotate(targetView.transform, -(rotation * 3)); //if you want easing
}
you will have to tweak it slightly based on what view or object you are targeting -- but thats pretty much it.
Hope this helps,
Michael
Shouldn't be too difficult. Just have somewhere in your code that handles the UIAccelerometerDelegate class and apply changes to your sprites based on the values you receive through parameters to the – accelerometer:didAccelerate: callback.
Apple docs for the delegate class are available at...
https://developer.apple.com/library/ios/#documentation/UIKit/Reference/UIAccelerometerDelegate_Protocol/UIAccelerometerDelegate/UIAccelerometerDelegate.html
In the delegate function of accelerometer just write the code -->>
float angleRadians = atanf((float)X_Position / (float)Y_Position);
float angleDegrees = CC_RADIANS_TO_DEGREES(angleRadians);
float cocosAngle = 1 * angleDegrees;
sprite.rotation = cocosAngle;
and the sprite will get rotated to desired angle with changes in the values of X_position, Y_Position and angle.
Njoy.. :)