In my LigGdx based game, I wish to move my Sprite in an elliptical path to reach the destination. I do not find any support in Universal tween engine. Sample of route example is shown below.
Questions :
Is there is any methods in UniversalTween Engine to have a elliptical path ?
Also let me know what is waypoints in UniversalTween Engine ?
Thanks in Advance !
The Universal Tween Engine now supports curves - Default is CatmullRom which would definitely be able to provide the smooth movement you want.
It's a little tricky to get your head around at first but not that bad once you get used to it.
Universal Tween Engine
Details of update that added curves
Well I have searched up this question for you and discovered you many people have already asked this question, and none of them got an answer, yet. So I will try to answer as best as I can. I believe that my method is not the best. But if your application is not time or performance sensitive, then this method may work.
Now this comes to a math problem. You know that the screen is make out of pixels and there is no point making it overly detailed because it isn't possible. So you can do this:
They grey line being your intended line, and the green line being your actual drawn line. If you move objects using the tween engine along the green path and switch path when hitting the red dots. You could mimic an elliptical movement. However, you need to use math and calculate your path. You could set the coordinates of your path as a constant for every screen size, or you could calculate it every time.
Overall, the more points you calculate, the more elliptical the movement will be.
Anyways if you look at this website, it teaches you how to tween.
You can use Tween.to(...); to help you tween to the points.
Hope this helped you
Related
I am currently working on an open world game like pokemon using libgdx.I am currently stuck on this effect that I really want to be done before moving to other features of my game. do you have any idea how to achieve this reflection effect? .concept behind?
https://gamedev.stackexchange.com/questions/102940/libgdx-sprite-reflection
For basic reflection, to draw a texture flipped vertically you can simply scale its height by -1. Then simply redraw the texture an appropriate distance under the player.
You shoudl also add a clipping rectangle around the water's edge so the reflection only draws where the water is. For perfomance purposes, it would also be good to only do this when the player is near water.
I can't give you actual code as I don;t know anything about your code, but once you've had a go at handling reflection as abaove, come back here and ask any more specific questions taht you may have.
This question is too broad and opinion based and hence is highly likely to be voted down.
Since I don't know english very well, I'm not able to find clear examples and/or tutorials for what I'm trying to do.
So the (maybe stupid) question is:
How can I strongly customize tweens using Starling framework and make my Sprites(or MovieClips) following a line, curve or create every other non-linear movement that doesn't exist in Transition Class?
I have no problem with Basic Starling animation. So it should be a good start point.
Thanks in advance for examples, resources or suggestions.
PS. I already visit the "Starling Wiki" page about custom Transitions but, as a Beginner(almost Intermediate) coder I wasn't able to completely understand it.
I know there are many online resources about AS3/Starling/Flash/Nape/Box2D but it's not easy for a non-english Beginner programmer to understand them.
You can simple move Starling's movieClip by set .x .y .rotation
Since now, I haven't heard of scripted transition to make predefined non linear movement. As you said, you can move object from one position to another, but it won't happen in a curved line.
What I've done in the past is to predefine the path of the movement, as I needed exactly the same weird path. I did a path tween in Flash, then used one simple function to loop through all frames (using gotoAndStop()) and getting x and y property of the object, storing them in an array. This was done when initializing. Later on I could start animation on all my weird paths whenever I wanted, using onUpdate method of tween, and passing positions from the array I've populated in the beginning.
This of course is good if you have very weird paths. If you want very little curves, you could try to do a mathematical equation. Tween classes have an update function, which will be called on each frame. So on each frame you could do some calculations and modify the parameters. For example if you tween x and y properties, you could use the update function to add a random number to those values. Of course this will make very uncontrolled movement, I'm just giving an example.
The best solution I could think of, speaking of complexity/result ratio - to use Greensock's TweenMax (look at the second example) - it has a built in bezier tweening. This means it could move from point A to point B within a bezier curve. I think this will be a good solution for your problem :)
I'm making a game with ActionScript 3.0. There's is one thing I can't figure out:
I have a big circle on the background. On this circle I want to let a character randomly move. But this character can only move on this circle, so it can't go to the background. Where do I need to start with this, how can i specify a specific stage like this?
P.S. I can't upload a picture yet, I've not enough "reputation points", otherwise I would have uploaded some pictures to get my question more clearly.
A general idea around which you can evolve is using hitTestPoint() method on your stage using current player's coordinates as the point being tested, and if this method returns false, this means the player has left the stage, and you need to put him back. Using previous location is the failsafe method, but you might also invent some other more smart way to do this.
The manual on hitTestPoint()
I'm working with a few programming buddies to create an AS interface to the kinect and one problem we're running into is image differencing. We need to be able to throw out image data that doesn't change from image to image so we can pin-point only things that are moving(i.e. people).
Anyone have any experience with this or a direction we can go?
I would consider creating a pixel bender shader to find the difference and also do any other math or tracking. Pixel bender gets its own thread outside of the normal flash player so you can get some more horse power for your setup. Pixel Bender shaders can be applied to bitmaps, vectors, or video so I think it is perfect for this project. Good Luck!
http://www.adobe.com/devnet/flash/articles/pixel_bender_basics.html
And is is a full collection of shaders including difference
Take a look at the threshold method on BitmapData.
It'll allow you to do this stuff. Their docs have a simple example so check that out.
It might be a long shot, and this is just me rambling, but in sound theory (strange how I'm relating it to image cancellation, but here goes...) the concept of cancellation is when you take a wave sample and add its inverse. It's how you make acapellas from instrumentals + originals or instrumentals from acapellas + originals.
Perhaps you can invert the new image and "normalize" the two to get your offsets? I.e. the first image is 'black on white' and the second image is 'white on black', and then detect the differences for the bitmap data. I know I did a similar method of finding collisions with AS3 a few years back. This would, in theory, cancel out any 'repeating' pixels and leave you with just the changes from the last frame.
With BitmapData your values are going to be from 0 to 255, so if you can implement a cancellation (because a lot of parts of the image are going to stay the same from frame t frame) then you can easily find the changes from the previous frame.
Just a thought! Whatever your solution is it's going to have to be quick in order to beat the flash runtimes' slow speeds. Your Kinect read FPS rate will be greatly hindered with bad code.
Here is some frame differencing code I wrote awhile back. It uses bitmapData: http://actionsnippet.com/?p=2820
I also used this to capture moving colors in a video feed: http://actionsnippet.com/?p=2736
Ok, so I'll try to be as descriptive as possible.
I'm working on a project for a client that requires a jibjab-style masking feature of an uploaded image.
I would like to be able to generate a database-storable object that contains anchor/control positions of a bezier shape, so I can pull it out later and re-mask the object. This all is pretty easy to do, except for one catch : I need to create the bezier object from a user-drawn outline.
So far, here's how I imagine the process going:
on mouse down, create a new sprite, beginFill, and moveTo mouse position.
on mouse move, lineTo an XY coordinate.
on mouse up, endFill.
This all works just great. I could just store the info here, but I would be looking at a GIGANTIC object full of tons of pretty useless x/y coordinates, and no way to really make fine-tuning changes outside of putting handles on every pixel. (I may as well give the end user a pencil tool...)
Here's what I'm thinking as far as bezier curve calculation goes :
1: Figure out when I need to start a new curve, and track the xy of the pixel on this interval. I'm imagining this being just a pixel count, maybe just increment a count variable per mouse move and make a new one every x pixels. The issue here is some curves would be inaccurate, and others unnecessary, but I really just need a general area, not an exact representation, so it could work. I'd be happier with something a little smarter though.
2: take each new x/y, store it as an anchor, and figure out where a control would go to make the line curve between this and the last anchor. this is where I get really hung up. I'm sure someone has done this in flash, but no amount of googling can seem to help me out with the way to get this done. I've done a lot of sketching and what little math I can wrap my brain around, but can't seem to figure out a way of converting pixels to beziers.
Is this possible? All I really need is something that will get close to the same shape. I'm thinking about maybe only placing anchors when the angle of the next pixel is beyond 180 degrees in relation to the current line or something, and just grabbing the edge of the arc between these changes, but no matter how hard I try, I can't seem to figure out how to get this working!
Thanks for your help, I'll be sure to post my progress here as I go, I think this could be really useful in many applications, as long as it's actually feasible...
Jesse
It sounds like a lot of work to turn pixels into Bezier curves. You could try using something like the Linear least squares algorithm. http://en.wikipedia.org/wiki/Linear_least_squares
A different tact, could you have your users draw vector graphics instead? That way you can just store the shapes in the database.
Another cool method of converting raster to vector would be something like this iterative program: http://rogeralsing.com/2008/12/07/genetic-programming-evolution-of-mona-lisa/
Good luck
In my answer to this question I discuss using autotrace to convert bitmaps to beziers. I recommend passing your user drawing through this program on the server. Autotrace does a fantastic job of tracing and simplifying so there is no need to try and reinvent the wheel here.
Thanks for the answers, although I guess I probably should be more specific about the application, I'm really only needing an outline for a mask, so converting images to vectors or polygons, despite how cool that is, doesn't really fix my issue. The linear least squares algorithm is mega cool, I think this might be closer to what I'm looking for.
I have a basic workaround going right now, I'm just counting mouse moves, then every X (playing with it to get most desirable curve) moves, I grab the xy position. then, I take every other stored xy, and turn it into an anchor, the remaining xys are turned into controls. This is producing somewhat desirable results, but has some minor issues, in that the speed at which the mask is drawn effects the number of handles, and it's really just getting a general area, not a precise fit.
Interestingly, users seem to draw slower for more precise shapes, so this solution works a lot better than I had imagined, but it's not as nice as it could be. This will work for the client, so although there's no reason to pursue it further, I like learning new things, and will spend some off the clock time looking into linear least equations and seeing if I can drum up a class that will do these computations for me. If anyone runs across some AS3 code for this type of thing, or would like some of mine, let me know, this is an interesting puzzle.