I'm quite new to as3, and I'm heading with a (for me complex) problem.
I have some identical objects (movieclips), wich I made draggable sqaures.
But I want to achieve the following thing:
When I drag one of these objects to another one, I want them to "attach" to each other, just like in some "building games".
And after two (or more) objects are attached, I need them to be draggable as a new whole.
Which means if you click on any of them, every object drags along, en they stay om the same attached position.
I honestly don't know how to do this.
I would appreciate if anyone could provide some examples or code.
Thanksin advance!
Here's a simple algorithm for you:
1) Make an array that will hold "draggable" objects.
2) Upon selecting the first object add it to the array.
3) On FRAME_ENTER move (translate) all the object that are in the draggable array and check objects in the array collision with other objects. If the collision is true, add those objects to the draggable item array.
People here won't write code for you, it's up to you. But if you run into a problem where your code does not work how you intend it, feel free to post it and surely some help will come!
Related
I'm new to Actionscript 3 and I'm trying to learn as much as I can.
I want to know how to move objects by clicking.
For Example: I will first click on object to select it then I will click on another object(not in the same location) to place the first one on top of it.
*Sorry if my explanation is bad
I don't have the code to show you because I don't know how to do it.
But the way that I thought of is:
- I will click on the first object to select it and that object will go to an array
- That array will have the function of the second click which will transfer the object on top of another one.
The problem is that there is chance that i can select two objects on the first one (It should be only one). Is there any way to fix this? Or is there a way to make this easier?
I am new to Lua scripting, and game development. So please I am just a noob in Lua.
I have searched the net for solutions to my problems, without any luck.
I use Photoshop, Corona, Dusk, json and Tiled on windows7.
I am creating a "board" like game, i.e. Setlers. I am using a world map, as the background. The background image of the game area is a world map (world.png file). I have no problem here.
I would like to create transparrent clickable objects matching the countrys borders on my gamemap with all parameters and values (I have added in Tiled) stored in the object. So When the player clicks on the country the transparrent object (on top of the map) is the one clicked and an eventlistener acts on the click.
In Tiled I can create all the objects I need, naming them + assigning parameters and other values.
If I add object.alpha value in Tiled, the alpha value is passed on to corona and working there.
How can I read these data from the json/tmx file in Corona and adding them to a lua table?
The way I am thinking to use the Tiled map and its objects, is to create one polyline trace of each country’s border (creating one object per country). Then place each “country traced object” on top of the world.png map, also naming the object with the countrys name like “object.name = TileBritannia” and also the other properties for use in game.
My problem is getting the objects info, like object.name, and an eventlistener reacting to a click on the object.
Is a polyline the right way to create a clickable area on a map, when I use a png file as a background image?
What is the best way to create a country border objects, in one layer or with all countries as individual object layers in Tiled.
Can I create one layer with sub objects and still access them in my code?
How do I get the object name and other properties, set in Tiled.
When I try to use the (local britannia = tiledMap:load("britannia.json")) the "load" is not working, getting a nil value.
I am looking for a code that will extract/get/read the object.name i.e. “objBritannia” or "TileBritannia". from the json/tmx file.
When I try to read the different parameters from the json file, I don't get the result I expect. I get the result = function: 046A73B0, was hoping for an object name of some sort.
Please provide links to or code example.
I have edited the question.
Thanks
For questions 1 and 2: I have not used Tiled, but based on Corona Tiled, you have the right strategy in mind. That page makes me think that you can just use tap event listener to detect tap. If you are having issues with the example on that web page, please update your question to be more specific. If tap event handling doesn't work (maybe you're talking about a different Tiled lib), look a Polygon fill and Point in Polygon detection, because that's basically what you need to do. Try some stuff from there. If it still doesn't work for you, then update your question with specifics otherwise it will be likely get closed (it is a little too broad as it is).
For #3, Lua is a dynamic language that supports adding properties to objects in one line. So upon the example on the Corona Tiled page, all you would have to do is
tiledMap = require("tiled")
local britannia = tiledMap:load("britannia.json")
britannia.name = "Britannnia"
local Zulu = tiledMap:load("zulu.json")
zulu.name = "zulu"
Naturally you will probably have a whole bunch so you will create a function that you call for each tile. It's not clear what map.layer["objBritannia "].nameIs("TileBritannia") is supposed to do so I can't comment.
I've been working a lot with AGAL vertex and fragment shaders. I've got individual objects lit correctly (including specular shading) but I'd like to have objects cast shadows on OTHER objects. I have looked online, but I think most people working directly with AGAL have built custom Stage3D libraries and the shadow-casting solution doesn't seem to be in the public domain. Anyone willing to change that?
I'd like to know how to get an object to cast a shadow on another. I can't post what I've tried, because I can't get my head around where to begin on this problem. How would you pass the information (whether other objects are blocking the light) into another object's shader?
Thanks.
IT's called Deferred shading, you have to do 2 pass of vertex and fragment shaders.
In the first pass you accumulate informations about distances, normals, occlusion...
In the second pass you render and apply the informations of the first pass to make shadows.
Another options is ShadowMapping:
Basic shadowmap
The basic shadowmap algorithm consists in two passes. First, the scene is rendered from the point of view of the light. Only the depth of each fragment is computed. Next, the scene is rendered as usual, but with an extra test to see it the current fragment is in the shadow.
The “being in the shadow” test is actually quite simple. If the current sample is further from the light than the shadowmap at the same point, this means that the scene contains an object that is closer to the light. In other words, the current fragment is in the shadow.
I'm wondering if there is a method to do a hit test object between two movieclips from the same class. The movieclips are being spawned into the stage using a for loop.
Is it possible to if(item(event.currentTarget).hitTestObeject(item(thats not being selected at the moment?))) I'm doing a drag and drop game and am trying to not let the items stack above each other when dragged to the snapping slots on the stage. If not is there other methods avaliable? Thanks in advance (:
first of all, detecting, whether two display objects (sprites, movieclips, etc.) hit each other, is independent of the fact, that the objects are instances of the same class. The important thing is, you have two instances and they are display objects, so you're good to go.
If you want to do hit tests, then i would do the following:
Create a helper class, that holds an Array of all the items, which have already been created.
That helper class needs to add itself as a listener to all the items for the event, that you start drag an item.
Once an item is dragged, the helper class adds itself as a listener to the mouse move event of that item
in the mouse move event handler, the helper class does a hit test from the currently dragged item to each item in its list of items (simple for loop)
if a hit test results with true, you save item you have currently tested against, as this is the one, that you dragged item is overlapping with.
Now you can do measurements (comparing positions, bounding boxes of the two items, etc) to figure out, where to position your dragged item, so that it does not overlap anymore.
Don't forget to remove the mouse move event listener in the event of the user ending to drag.
A few weeks ago I was working on a project wich had very specific dragging, so we've decided not to use the Flex DragManager. Our, so called, DragManager is not doing anything special. The thing that I think is related with your work is the presence of snap blocks. In our case the snap blocks were simple groups. Every snap block has a reference to the object wich was dropped into it(let's say it is droppedItem). When trying to drop an item, or even before triggering the snapping mechanism, there is a simple check in the snap block
if (droppedItem == null)
And this was the solution in our case.
I'm not sure what are your snapping slots, but I hope that our approach will help you.
Best regards, Ivan
Im looking for an easy to use method of assigning drag behavior to multiple objects (images, shapes etc) in canvas. Does anyone have a good way or know of any libraries for dragging objects around? Thanks
Creating your own mouse events takes a little work - ideally you should either create or use some kind of mini-library. I'm thinking of creating something like this in the near future. Anyway, I created a drag and drop demo on jsFiddle showing how to drag images - you can view it here.
You can create draggable images like this:
var myImage = new DragImage(sourcePath, x, y);
Let me know if you have any questions about this. Hope it helps.
EDIT
There was a bug when dragging multiple images. Here is a new version.
Another thing you might want to check out is easeljs it sort of in the style of AS3... mouseEvents dragging etc...
The HTML Canvas—unlike SVG or HTML—uses a non-retained (or immediate) graphics API. This means that when you draw something (like an image) to the canvas no knowledge of that thing remains. The only thing left is pixels on the canvas, blended with all the previous pixels. You can't really drag a subset of pixels; for one thing, the pixels that were 'under' them are gone. What you would have to do is:
Track the mousedown event and see if it's in the 'right' location for dragging. (You'll have to keep track of what images/objects are where and perform mouse hit detection.)
As the user drags the mouse, redraw the entire canvas from scratch, drawing the image in a new location each time based on the offset between the current mouse location and the initial mousedown location.
Some alternatives that I might suggest:
SVG
Pure HTML
Multiple layered canvases, and drag one transparent canvas over another.
The HTML Canvas is good for a lot of things. User interaction with "elements" that appear to be distinct (but are not) is not one of those things.
Update: Here are some examples showing dragging on the canvas:
http://developer.yahoo.com/yui/examples/dragdrop/dd-region.html
http://www.redsquirrel.com/dave/work/interactivecanvas/
http://langexplr.blogspot.com/2008/11/using-canvas-html-element.html
None of these have created a separate library for tracking your shapes for you, however.
KineticJS is one such Javascript Library that u can use exclusively for animations
Heres the Link html5canvastutorials
Canvas and jCanvas
You're definitely gonna want to check out jCanvas. It's a super clean wrapper for Canvas, which kicks open a lot of doors without adding code complexity. It makes things like this a breeze.
For example, here's a little sandbox of something close to what you're after, with dragging and redrawing built right in:
Drawing an Arrow Between Two Elements.
I ventured down the road of doing everything with DIVs and jQuery but it always fell short on interactivity and quality.
Hope that helps others, like me.
JP
As you create new objects whether they are windows, cards, shapes or images to be draggable, you can store them in an array of "objects currently not selected". When you click on them or select them or start dragging them you can remove them from the array of "objects not selected". This way you can control what can move in the event of a particular mousedown event or mousemove event by checking if it isn't selected. If it is selected it will not be in the "not selected" array and you can move the mouse pointer over other shapes while dragging shapes without them becoming dragged.
Creating arrays of objects you would like to drag also helps with hierarchy. Canvas draws the pixels belonging to the foremost object last. So if the objects are in an array you simply switch their instance as in element in the array say from objectArray[20] to objectArray[4] as you iterate through the array and draw the objects stored in the array elements you can change whether other objects are seen on top or behind other objects.