I have a b2PolygonShape body and apply a force to it.
_recbody->ApplyForce( b2Vec2(6.0, -6.0), _recbody->GetWorldCenter() );
I want to change the centre of rotation of the body to be more in the front of the body. So that applyForce and also collisions make the body not turn in the centre but more in the front.
I'm trying to create spinning shapes floating in space. There is still gravity in the environment, however it should not affect these platform objects because they are static (right?). How can I apply a constant angularVelocity to it though? It doesn't seem to apply when I assign it a value, probably due because it's static.
The simplest example would be a spinning gear, an automated teeter-totter (not influenced by external forces). All I'm trying to make is a spinning rectangle that could interfere with a ball controlled by the user.Do I need to use Joints to pin it in place? How can I specify the details of not being influenced by the dynamic objects?
I have a movieclip and when I do 3D rotation from Transform panel, It rotates perfect, center is in the middle of image, and when I apply mc.rotationY, rotation center is in left of the image, aren't 3D rotation from Transform panel and mc.rotationY from AS same? what's up?
View 2 RepliesAs you can see in my code, I'm trying to adjust on the fly the x and y properties so that the movieclip gives the impression to rotate from its center and not from its corner at 0,0
Code:
var myclip:MovieClip = new MovieClip();
myclip.buttonMode = true;
myclip.graphics.beginFill(0);
[code]....
but it doesn't work and the clip does not rotate well
I am trying to rotate a Sprite in three dimensions around its centerpoint, and I am struggling to understand some of the behavior of matrix3D.
Ive overridden the set rotationX, rotationY, and rotationZ methods of the Sprite as follows:
override public function set rotationX (_rotationX:Number) : void {
this.transform.matrix3D.prependTranslation(this.width/2.0, this.height/2.0, 0);
this.transform.matrix3D.prependRotation(-this.rotationX, Vector3D.X_AXIS);
[Code].....
I am using prependTranslation to correct the centerpoint of the rotation, and the first prependRotation to cancel out any previously-applied rotation.
Testing it out, rotationX works exactly as expected, and the Sprite rotates around its horizontal axis.
rotationY and rotationZ also appear to work fine. However, there is one problem: whenever rotationY or rotationZ are set, all of the other rotation values change as well. This is not a problem with rotationX -- if I set rotationX, nothing else changes. But if I set rotationY or rotationZ all the rotation values change, which is a problem for my app (which is trying to save and restore values).
I think I am just lacking some understanding about what is going on with matrix3D. How can I implement this so there is no interdependence between the values?
I am new in action script 3... i am not able to rotate movie clip from center point(movile clip is a containear holding many clips).
View 9 RepliesAs is well demonstrated by a Google search, the rotationX, rotationY, and rotationZ properties turn a display object around the center.
That's all well and good, but I want to rotate a display object about a different point.
I can't believe there isn't a way to do this, but I don't see anything that addresses this question specifically.
I found this actionscript online to rotate a sprite around its center point but I get two errors when I use it. 1084: Syntax error: expecting identifier before leftparen. 1084: Syntax error: expecting rightparen before leftbrace. Also, in place of angleDegrees do I put in the angle I want the sprite to rotate by?
var point:Point=new Point(spr_box.x+spr_box.width/2, spr_box.y+spr_box.height/2);
rotateAroundCenter(spr_box,45);
function rotateAroundCenter (ob:*, angleDegrees) {
var m:Matrix=ob.transform.matrix;
m.tx -= point.x;
[Code]...
I coded an entire file based on the top left registration point of my movie clip. I want it rotate it to point at the cursor, but since the registration point isn't in the middle.. its not a perfect rotation around the center of the mc. Is there anyway to rotate it around the center of the movie clip without changing the registration point?
ActionScript Code:
stage.addEventListener(Event.ENTER_FRAME, aimBall, false, 0, true);
function aimBall(event:Event):void {
ball_mc.rotation = getAngle(ball_mc.x, ball_mc.y, mouseX, mouseY) -90;
trace(ball_mc.rotation);
} function getAngle(x1:Number, y1:Number, x2:Number, y2:Number):Number {
var radians:Number = Math.atan2(y1-y2, x1-x2);
return rad2deg(radians);
} function rad2deg(rad:Number):Number {
return rad * (180/Math.PI);
}
url...I'm using this code i made some changes like changing the array for a xml.In some part i put a button to stop the movement and i used [code]
and it works perfectly, but then i want to return with another button to the movement. and i can't make it work.
Is it possible that I can have a fixed 3d rotation center for a movieclip.So if I have two movieclips spaced apart and I have rotated them, they rotate in their own axis rather than based on a single axis.
View 6 RepliesI draw a shape,like follows:
var shape1:Shape;
shape1=draw();
addChild(shape1);
shape1.rotation=50;
[Code]....
Then I want to rotate the shape at it's center point(200,202) by using shape1.rotation=50,but I find the shape don't rotate at the the center of it's shape. How to realize the function which make shape rotate at its center point?
Has anyone got a bit of code I can use to change the center point DisplayObjects rotate around in a 3D space? I need it to work with rotationX, rotationY and rotationZ. I know theres a workaround of wrapping every object in aother sprite and offsetting the x & y positions but I'd much prefer a math solution. As an example of the problem, this code should make a star shape:
[Code]...
I am trying to place leaves in a circle to create a flower with code. I run into some problems.Is it possible to rotate the leaves so they all rotate in the direction of the center of the flower? And is it possible to calculate how many leaves can fit around a certain circle radius without to much overlapping?
View 1 RepliesUsing the new 3D features in CS4. I know you can change the 3d center point manually via the Transform panel, but does anyone know how to do this dynamically at runtime? (ie via code)
View 1 RepliesI have a MC in an AS3 animation and I want to increase its height from bottom to top which would mean that the registration point should be bottom of the MC and center of width (horizontal center).
View 2 RepliesWhen you create shape on stage and right click and chose create object you can chose Registration point for the object..you chose what corner will be used as center of coordinates for this object. Now onice you create object is there way to change this registration point e.g. i created it in center now i want to to be in upper left corner?
View 2 RepliesI'm making a game like Arkanoid and to move the ship with mouse, I'm using the following code :
var mousex:int = costume.stage.mouseX;
if (mousex < paddleWidth/2)
mousex = paddleWidth/2;
else if (mousex > PhysiVals.STAGE_WIDTH - paddleWidth/2)
[code]....
Everything's going fine there! The paddle is moving the way it should! The problem is I want a little inclination towards the direction its moving and when it stops moving the angle of inclination should become zero.
I'm working on a AS3 Game Engine at the moment utilizing Box2D (2.1a) and 2D shadows. I have Box2D down but I've yet to find a way of drawing 2D shadows efficiently.I was following this tutorial only to be disappointed by the speed at which it rendered the Box2D shapes and the shadows.I was getting the vertices of the objects via this function:[code]And using it to draw the shadows via the AS3 graphics api.Can anyone recommend me a better more efficient way of programming 2D shadows?
View 2 RepliesIn the flash CS4 transformation window (Ctrl+T opens this window) you can set the 3d rotation and 3d rotations points. Changing the 3d rotation in actionscript is simply..
this.rotationX=90;
this.rotationY=90;
this.rotationZ=90;
But I cannot find any way to change the 3d center point in action script. Have been trying things like centerZ=40; centerRotationZ=40; etc...
Is there anyway to reposition the axis for rotation Z?
View 3 RepliesI'm making a Flash game, and I've encountered a really weird problem while trying to draw a polygonal shape in Box2D.
Here's the code I use:
var fixtureDefs:Array = new Array();
...
var fDef:b2FixtureDef = new b2FixtureDef();
fDef.density = 0;
[code]....
Where vertexArray is a valid array containing 4 b2Vec2 vertices, making up a convex shape.The problem is, when I test, collisions don't work right for that body. Most other objects -enemies, user-controlled characters - pass straight through, as if the body isn't there at all. Some raycasts pass through as well.
Infuriatingly enough, one kind of bodies I have (a custom enemy) somehow does detect the body and collides with it. The raycasts that particular kind of enemy attempts do work - when your character hides behind the polygon, it's like they can't see him.The other weird thing: when I try the same code, only go for SetAsBox instead of SetAsArray, it works exactly as it should.I'm using a custom ContactListener class, but I haven't done any contact filtering (unless it's possible to do that without realising).I'm using the Flash 9 version of Box2D 2.1a.
i'm using flash with box2D 2.1a. i'm rotating ball hanging on the string. The path which the rotating ball trace is ellipse. When releasing the rotating ball from the string i want the ball to fly with the obtained direction, velocity and strength. As you can see in the pictures.[URL]..I've tried to do it with setPosition (method of b2Body) and with various joints. But I haven't got the needed results.
View 2 RepliesI know that trying to model character movement in Box2D is always hard/impossible, but I'm trying to see if there's any way to make an user-controlled object that cleanly slides against other objects, going up or down, that makes it look like the character is climbing/walking up or a down. The character could be modelled as a circle if that simplifies matters, but I don't see how I could get this effect using just a circle with a joint motor.
There's a "wheel joint" in the C++ version of Box2d, which I suppose I could port to Flash, but I don't know if that would give the correct effect either. Another idea I had was to have the character do little jumps, based on the normal of the object that it is touching. But I suspect that at corners, or at contacts with multiple objects, this will give weird results.
Is it possible to modify a shape within a body after assigning it, for example I have a box shape for my game hero body, and when I press the down arrow I want my hero to crouch witch means that I need the body shape to be resized.
I've already searched in google but it appears that the topic of modyfing shapes is not so popular. If it's impossible maybe you know a better way of doing this.
I'm attempting to write a racing game. I've loaded in my image, I brought it to the stage and now, all I want to do is rotate it from its' center and not upper left corner.
The code:
racer.rotation += 5;
rotates from the upper left corner. How do I rotate from the center of the car/sprite? I've tried putting it into a container but I'm unsure on the coordinates of the container because I tried to set the x,y coordinates to half the sprite image but y'know, it's not doing what I expect it to.
ActionScript Code:
if (arrowLeft) {
var container:Sprite = new Sprite();
[Code]....
I will never sneer at another racing game! I didn't think it would be this hard to do a simple rotate of an image!
Let's say I have a tween that makes my MovieClip thingie go from point A to point B.Somewhere in my code, I want to rotate thingie by modifying its rotation attribute, without breaking the tween that makes it go from A to B.
View 5 RepliesI want to know if box2d b2BodyDef has a massdata property or if it can be accessed in some way. I am not sure whether this can be done in Cocos2D but I have seen it in the flash code I am trying to re-implement in cocos2d.Here is the the code that brought about the question.
[Code]...
I want to make a movieclip moves smoothly and when it changes the direction, it can turn smoothly but not a sudden turn, I try out the code below. and the truning is odd:
this.rotation = (Math.atan2(targetY-this.y, targetX-this.x )/Math.PI)*180;
i am listening contact between dynamic bodies. But cannot listen contact between dynamic and static bodies .
I can handle collision detection on my b2contactListener class with this metod.
public override function BeginContact(contact:b2Contact):void {
// getting the fixtures that collided
var fixtureA:b2Fixture=contact.GetFixtureA();
[Code].....