I am working on flash professional cs5.5 and actionscript 3. I need to use symbols of customized sizes to test the hitTestOjbect() function. However, when i convert the bitmap to a symbol, by default it goes into a rectangular size and the empty space all around is also detected as part of the symbol.
Is there any way to keep the size of the symbol customized ?
That is the nature of a bitmap. Technically, bitmaps are always rectangular. Transparent areas are just fills with alpha-0. When you convert a bitmap to a symbol, the bitmap still exists, just inside the context of the symbol.
One of the fastest ways to fix this is to use a mask inside your MovieClip. Create a plain drawing object in the exact shape of the hit area you want. Then, place that on your timeline on it's own layer. Right-click the layer with the mask, click "Mask", and then drag the bitmap's layer under the mask one. Lock both layers, and exit symbol editing.
Now your hit area will be limited to only the masked area.
EDIT: I appear to be mistaken - hitTestArea is always rectangular. See the top answer to hitTestObject Collision Not Registering Correctly.
Related
I have a flash object that is comprised of three layers...
the top layer 'Layer1' is a layer where a bunch of stuff happens for the program to run (drawing shapes, movie clips, etc) using as3... the next two layers just sit underneath and serve as a background image to the main program that is happening on 'Layer 1'. I want to programmatically add shapes and sprites and things to the 'masklayer' so that I can update the mask layer programmatically as well...however I can't seem to figure out how to do this...anytime i try to access the object it defaults to the top layer...anybody know?
The layers on your timeline only exist in the editor. There are no "layers" in a compiled swf.
To manipulate the ordering of a display object at runtime, you can use addChildAt(). This works even if the display object is already a child of that container.
However, it's generally better to avoid that by creating parent display objects at design time. For example, you could create movie clips called maskContainer and imgContainer and whatever you want to have on the bottom you could add using imgContainer.addChild().
I am making a game in AS3 for a school project (using the AIR api). I have about a year's worth of experience in AS3, so i would say i'm proficient but not an expert. Anyway, i have never attempted to do sprite animations in AS3 and i'm not quite sure how to approach it.
If i create a list of bitmaps and call addChild() and removeChild() to display each frame of the animation, it would affect the framerate as these functions are not very efficient (i have tried this before and it tanked my framerate if i had too many animations going at once). I have also tried creating a list of BitmapData objects, adding a bitmap to the display list, and then pointing it to a different BitmapData each frame, but this does not seem to work at all.
So what is the best way to do this? In XNA, for example, i would create a sprite class that draws to the screen using a sprite batch, then i would create a list of sprite objects and cycle through them to create the animation. Is there any way to achieve a similar result in actionscript?
First (simple) method: you can just use multi-frame MovieClip for animation. Put an image in each frame, put a MovieClip on the stage and that's all. You can control this animation using play(), stop(), gotoAndPlay(), gotoAndStop(). It will work without much problems for a generic platform game (I did that myself long ago).
Second (advanced) method: use bitmap blitting. For each animation, create a bitmap image that holds each frame of the animation. Use this image as a source for copying pixels into your current animated object. You just need to copy a particular rectangle area inside a source bitmap that corresponds to the current frame.
The actual blitting happens here
destinationBitmapData.copyPixels(sourceBitmapData, areaRectangle, destinationPoint);
Where destinationBitmapData is your "canvas" that you're blitting to; sourceBitmapData is the source image holding all animation frames; areaRectangle is the Rectangle inside the source image defining which area to copy; destinationPoint is left-top coordinate of the copy area in your canvas.
The destination canvas can be just one small object (like your game character that is moving around) or the entire game screen with all objects. I.e. instead of blitting and adding each object separately, you can just have one big canvas and blit any necessary parts directly to it.
That said, there is already a number of various ready-made engines that use blitting and even advanced techniques like 3D acceleration for 2D sprites.
One of them is Starling.
I'm currently doing the following when applying a mask to a MovieClip:
mc1.cacheAsBitmap = true;
_mask.cacheAsBitmap = true;
mc1.mask = _mask;
Which works great, however...
mc1 is a complex vector animation, and cacheing it as a bitmap in order to mask it has pretty big memory implications from what I can see, and have read.
Is their another way to implement masks? Or a way to optimise the usual solution?
Thanks
edit
Both the mask and mc1 are MovieClips, and they have been added to the stage, the mask is a gradient.
I am using Flash CS6, both movieclip and mask are added to the timeline, where they are being animated
You can use http://www.greensock.com/blitmask/
Quote from the documentation:
Can’t I just set the target DisplayObject’s cacheAsBitmap property to true and get the same result? Why use BlitMask?
If you set a DisplayObject’s cacheAsBitmap property to true, Flash takes a bitmap capture of that object so that when you move it (only
altering the x and/or y properties), the text and vectors don’t need
to be re-rasterized again before being rendered to the screen.
However, Flash would still need to concern itself with extra pixels on
every frame if you’re masking them to only show a small portion of the
area. BlitMask, however, only cares about that smaller masked area
(after the initial capture of course) which alleviates Flash from
having to even think about the extra pixels.
I'm a bit confused. If I import a png picture, drag it onto my stage, and right click > convert to bitmap. Is that the same thing is if I have a vector created in code, and then apple cacheAsBitmap = true?
A PNG picture is a raster object, and it has a parent class of Bitmap already. You might, however, encapsulate that Bitmap into a drawn rectangle (effectively making a rectangle with bitmap fill, that is actually a vector object), and then convert to bitmap, applying cacheAsBitmap = true to the vector object made of the raster object. I don't understand why do you want double transformation raster->vector->raster in the first place. Probably Flash isn't so stupid if you just drag a library asset made out of a PNG to the stage, it'll make you a Bitmap based object instead, and "convert to bitmap" won't do a thing.
I am working on a Action Script 3.0 application , in which i ill be allowed to load the image and make them draggable. Consider i am loading the deer image and making it as draggable.
Problem with this is , if i click on the translucent area ( white space around the bitmap ), i dont want the bitmap to draggable.is there any way to draw the deer boundary region exactly without the white space around it.
You can use BitmapData methods to get each pixel color, and then, you can either :
On creation, for each pixel if it's not fully transparent (!= 0) you can draw a point of a Shape, which will be transparent, and make it dragable in place of your bitmap (as noticed in comment, it will be quite CPU consuming, so use the second method)
On click, get the click coordinate relative to the bitmap, check if the pixel is transparent and make it drag only if it's not.
In either way, that will be quite CPU consuming. You may also consider convert your bitmap to a vector image (Sprite). This will allow flash to detect real images boundaries.