I'm trying to simulate a falling balloon in Box2DAS3. What is important is that balloon falls the such that the bottom part were you blow it up rotates towards the bottom if it's knock sideways or is dropped at an angle.
alt text http://lh4.ggpht.com/_gjsCWAV_CZc/Sw7zqHahTJI/AAAAAAAAC3s/YIJka4AsM5s/s144/Untitled.jpg
I've tried offsetting the center of mass of the body and also joining two bodies together with the denser one representing the tie. In both cases the body falls at the same angle without rotating.
An object in free fall (vacuum), without any initial linear or angular velocity, will never start to spin by itself, no matter where its center of gravity lies. You need to simulate fluid drag and buoyancy. A simple way to this is to add a small force on the top of the balloon that points upwards.
Add a drag force to all objects. Something like -velocity / drag_amount
Related
Say I have a MovieClip of a non-rectangular shape. For an example I've attached a file called Symbol1.png. In this attached file, I've rotated the symbol instance. Of course, this causes the bounding box to rotate as well.
Now say I place that rotated symbol instance inside another symbol. I've illustrated this in the attached file called Symbol2.png. Note that the bounding box now includes the overhanging corners of the rotated symbol that is inside.
Is there any practical way to determine the apparent bounding box of Symbol2 without including the corners of Symbol1's bounding box? I'm trying to zoom and rotate to an automatically calculated size and angle, but this overhang problem is causing a lot of extra space to be included in my final zoomed perspective.
Thanks.
Every container's bounding region is defined by the space that its children occupy. What you're looking for isn't the "bounding box" per-say (as Flash is accurately representing this), but rather the visible space the children occupy (which is much harder to quantify).
Thankfully, you're not the first to ask this, and (technically) this is a duplicate of Calculate Bounding box coordinates from a rotated rectangle
I am trying to get an effect like this:
http://www.welcomeanimations.com/welcome_animated_gifs_rotating_sign_orange_chrome_k_1.htm
I have tried all sorts of things:
Matrix translation/rotation - spins the text around the 'Z' axis, instead of 'Y'
Adding TextField to a sprite, and Sprite.rotationY++: reg. point is upper left corner
Adding to MovieClip - same as above (an article said MovieClip's reg. point was centered).
This should be trivial?!?! Help me stackoverflow, you're my only hope!
So you have to remember, Display objects scale and rotate around their local coordinate system. so when you put a textfield in a sprite, you need to center it in that sprite's coordinate system. And doing that for textfields is annoying because their width/height isn't always accurate but there is trick for that: get visual bounds, but normally you can take half of somethings width and height
I've created a prototype for you on wonderfl so you can see the solution working in action. Click on the blue square to see how the local coordinate system messes with the rotation
Finally as you use thing you might find things not rotating in 3D space quite right, this should be able to fix that.
I have this background that I'm using for a section, and it starts with a small arrow engraving at the top:
However I'm trying to get it when it repeats to clip out the top arrow part, just leaving the texture in the middle part. I was wondering if it was possible to do it with something like webkit? Thanks
You can't. You need to come up with another method of doing so. There are a number of ways to do this. Personally, I would use only the arrow, but use inner box-shadow for the shadows on everything else. This way you have smaller image being used, and it will always fit the size of the container.
Break up the background image from the pointer and make the two separate sprites. You can get tricky with the pointer and have it point in all 4 directions in the same image. This will allow you to pop up the bubble in all directions from the source.
You can't repeat both x and y on a usable sprite.
I have a maximum of three sprites in my projects.
One for non-repeating elements, another for repeat-x, another for repeat-y.
I find the clip property pretty much useless.
I have a spotlight that moves on a stage.
Now I rotate the spotlight but its not rotating on the correct point/origin.
I am trying to do something like
myOject.setOrigin = {x , y};
//and then rotate it about x,y.
I have manually set the white circle in the correct place and when I rotate the
object with the mouse on the screen it works.
Can somebody help me?
Make sure the registration point is in the middle of your symbol. It's not the white circle that appears when you use the Free Transform Tool:
But the crosshair that appears when you edit your movie clip:
You can easily center the object by selecting everything, then opening the Align panel and aligning its horizontal and vertical axes to the center using the two "center" icons under the Align section. If your MC has multiple items per layer, group each layer before aligning, then ungroup after aligning:
The white circle is not what will be used as the origin, it's the little cross. Adjust your clip to have that in the center (you'll have to move all of it's contents). Another option, if moving is not possible, is to wrap your clip in another clip and move it within that.
Select symbol and click CTRL+E - Then move it to positioning cross.
I'm working on a swing program to display several pictures. And one can rotate the picture (implemented each as a JComponent).
Problem is, when a picture gets rotated, the border of the JComponent doesn't change so that the picture gets clipped.
Is there any way to also rotate the border so that the picture can be fully drawn?
(I know one can calculate the new size of the border, but it leaves empty space on the edge. When a rotated picture overlaps with another and one want to move the one underneath, one cannot do that because the event will be passed to the picture above, onto the transparent edge. So it is more ideal if one can just rotate the border).
Execute another pack() on your top-level JFrame after rotating.