In p5.play I want to set a sprite's opacity(like Fade). How can I do that?
sprite.opacity = 0.5 //something like that
There are two ways you can do this, depending on what you're trying to make transparent.
Changing the color
This method can only be used if you don't plan on adding images to your sprites. We can use this basic function:
sprite.shapeColor.setAlpha(50)
As I said, this method can only be used with colors.
Changing the images
It is by no means efficient, but it technically works
tint(255, 0-255);
drawSprites(sprite);
tint(255)
I'm using Builder v1.80.06
I can vary the position of a polygon every repeat easily enough
e.g. I have a Positions list
positions=[[1,1],[1.1,0.9],...]
and in the 'Position field' have :
$positions[0]
and then change it's value in a code block on each repeat.
BUT I want to vary the size in a similar manner with a $sizes list but get an error.
Looking at the generated code, the problem is at the object creation stage. the code generated is:
for a hard coded polygon (ie ok)
polygon_1 = visual.Rect(win=win, name='polygon_1',
width=[1.5, .2][0], height=[1.5, .2][1],
ori=0, pos=[0, -0.6],
lineWidth=1, lineColor=[1,1,1], lineColorSpace=u'rgb',
fillColor=[0,1,0], fillColorSpace=u'rgb',
opacity=1,interpolate=True)
for one populated by a variable (not working):
polygon_2= visual.Rect(win=win, name='polygon_2',
width=1.0[0], height=1.0[1],
ori=0, pos=[0,0],
lineWidth=1, lineColor=[1,1,1], lineColorSpace=u'rgb',
fillColor=[1,0,0], fillColorSpace=u'rgb',
opacity=1,interpolate=True)
It complains (rightly) that 1.0[0] makes no sense on the width and height parameters
Even though I have my sizes list instantiated in a code block right at the beginning of the experiment instead of reading $sizes[0] a default float value of 1.0 is used.
Any other suggestions for how to vary the polygon size dynamically at runtime using builder?
I could just take the generated code and drop it into coder I suppose and fix the problem but I want to hand this over to a researcher so would like for them to be able to maintain it.
thanks,
If you set size to be a tuple/list with a pair values [1.2,1.5] or [1,1] does that not fix it?
When you change attributes at runtime, just change the attribute of an existing stimulus instead of instantiating a full new stimulus. The latter is quite heavy on ressources, causing unreliable timing. So do
stim = visual.Rect(win) # instantiation, ressource heavy
stim.attribute = newValue # change attribute. lighter.
I can think of two ways you could do it in a pretty neat way. The first is to set width and height explicitly instead of the size attribute, but using a size-like value. So (removing all parameters not of interest):
polygon_2 = visual.Rect(win)
# Unpack the x,y-sizes to the stimulus .width and .height attributes
newSize = (1.5, 0.2)
polygon_2.width, polygon_2.height = newSize
The second, if the size attribute is really important to use, is to use the Polygin with edges=4 to make it a rectangle:
polygon_2 = visual.Polygon(win=win, edges=4, size=(1.5, 0.2))
# Setting size
polygon_2.size = (0.8, 0.4)
Do try Jon's suggestion first. But the idea with visual.Rect and visual.Circleis to use substitute Polygon's size and vertices for something more relevant. So size can do unexpected things if width/height etc. are not 1.
I've got the following node set as follow.
box.physicsBody.allowsRotation = YES;
No mater what force applies to this box, I want it to never fall down or rotate more than a certain angle, just like a tree or a spring that might bend all the way down but has a tendency to go back to it's initial angle or position.
Is there a any trick or method to that?
I was thinking maybe joining an invisible un-rotatable physics body under the box and use a joint spring method for that which I have no Idea how that works!
Or, maybe there be a trick to play with the pivot. Any idea?
In the update: method you will have to continuously check the desired node's properties. In your case it is going to be the zRotation property of your node.
Add this code in your update: method:
if(yourNode.zRotation > 0.5)
yourNode.zRotation = 0.5;
if(yourNode.zRotation < -0.5)
yourNode.zRotation = -0.5;
Change the 0.5 value to your desired value or replace it with a static const float.
I am trying to make a simple as2 shooter but when I try to shoot an enemy the bullet just go thru it and doesn't remove the enemy. I tried to put
if (hitTest(_root.vihollinen)==true
){
_root.vihollinen.remove();
this.removeMovieClip();
}
but nothing happens
Most of the code is just copy/paste because I don't know much about coding but I'm trying to learn!
https://www.dropbox.com/s/58u34tbeve6oile/game.zip
The most significant issue is that your enemy needs an Instance Name in order for the code to understand it. Simply click on your enemy movieclip, and add vihollinen to the Instance Name field at the top.
Next, your bullet code is close, but needs some adjustments. Here is your code:
_root["bullet" + bulletsFired].onEnterFrame = function(){
this._x += this.xmov;
this._y += this.ymov;
if (hitTest(_root.vihollinen)==true){
_root.vihollinen.remove();
this.removeMovieClip();
}
};
If you're ever using an onEnterFrame handler like that with a function, it's good practice to always refer to the current object with this, like so: if(this.hitTest(_root.vihollinen) == true){
remove() is not an ActionScript2 function. Try using unloadMovie() instead, like this: _root.vihollinen.unloadMovie()
Changing those three things will make your code function. Be sure that you try to go through each part of your code and understand it to the best of your ability - it'll make things much easier in the long run, even if it takes a long time to figure out why each part is there!
How'd I go about this one? I want to tween a value from one to another in x time. While also taking into account that it'd be nice to have an 'ease' at the start and end.
I know, I shouldn't ask really, but I've tried myself, and I'm stuck.
Please assume that to cause a delay, you need to call function wait(time).
One simple approach that might work for you is to interpolate along the unit circle:
To do this, you simply evaluate points along the circle, which ensures a fairly smooth movement, and ease-in as well as ease-out. You can control the speed of the interpolation by changing how quickly you alter the angle.
Assuming you're doing 1-dimensional interpolation (i.e. a simple scalar interpolation, like from 3.5 to 6.9 or whatever), it might be handy to use Y-values from -π/2 to π/2. These are given by the sine function, all you need to do is apply suitable scaling:
angle = -math.pi / 2
start = 3.5
end = 6.9
radius = (end - start) / 2
value = start + radius + radius * math.sin(angle)
I'm not 100% sure if this is legal Lua, didn't test it. If not, it's probably trivial to convert.
You may look at Tweener ActionScript library for inspiration.
For instance, you may borrow necessary equations from here.
If you need further help, please ask.