I have a pygame screen with multiple tree like objects which grows with each update. I also have to draw random circle which appear and disappear with each update.
I am not able to make the circles alone to disappear. If I try to redraw I loose the slowly incrementing tree structure also. Any help
Using sprite groups (http://www.pygame.org/docs/ref/sprite.html#pygame.sprite.Group) you can put all the tree like objects into a sprite group designated for trees. Then at the end of the game loop you could blit the background onto the screen and call "tree_group.draw(screen)" to draw all your tree sprites wherever they may be on the screen. With that in place, you can simply draw a random circle wherever you'd like without worrying about taking corrective measures and trying to fix where the circle was drawn previously. Using sprite groups makes updating in game loops a breeze as well. Just call "tree_group.update(args)" and every object in the group will update with the arguments passed in.
Related
I have several images in my scene, I managed to make the zoom and pan work but the problem is, All of the images are zooming in at the same time. The scripts are place on each gameobject. I used gameobject for the images.
You need apply a filter so you just appli the transformations to one game object, since every one of them are GameObjects I recommend use raycast to sellect an object and then activate his Zoom.cs script just for this object.
I sugest to use just one Zoom.cs in the scene instead of every object having his own copy, then change your function to work with one game object as a paremeter and, when you touch your game object then that object will be the one to suffer the transformation.
If you doesn't want to implement a raycast or change your function at all, then you could set all the images inside a matrix, or use an index system, the central image, or the index you designed, will be the one to suffer the transformations. so you can scroll betwen your gaery and be sure that just the image that you designate in your matrix/index will be the choosen one. The trouble here is that you need to fully control the scroll animation so no one of the images will be in a wrong place like in between two index.
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 have my player dragged around the stage. If the player hits any object(All perfect rectangles) that I lay out in a movieclip, I'd like the player to hit a wall and stop moving. What's the most efficient way to write this?
Do I loop through all the points the player can't hit?
There are built in methods for hit testing, you loop through all the objects you want to hit test against (make each it's own sprite or hit test the entire sprite that contains all the parts against the object depending on what kinds of info you want to have. You may also want to rig up your own custom Sprite that has hit regions for the left right top and bottom to determine which edge the player has hit.
http://help.adobe.com/en_US/FlashPlatform/reference/actionscript/3/flash/display/DisplayObject.html#hitTestObject()
Multiple hittest AS3
I'm working on a game that allows players to click on a card and drag it across the screen in any random direction. There are a total of 64 100x80 overlapping cards on a 800x800 canvas at any one time and each one is a procedural draw. As some of you probably suspect, canvas doesn't like redrawing that entire canvas for every move. To work around this, I'm utilizing a buffer canvas to draw the card and then attempting to paint that buffer canvas to the main canvas using drawImage(). To ensure there is no drawing buildup, I clear the region of the canvas associated with where I plan to drawImage() using a clearRect().
The problem I'm experiencing is that because the (x,y) coordinates used for the clearRect() and drawImage() are coming from the location of the mouse, if the user moves too fast, the coordinates will differ from the time drawImage() was last executed to the time clearRect() is called during the next draw sequence. The result is residual draw from the last sequence - proportionate to how fast the card is being dragged.
I tried maintaining the (x,y) coordinates from the drawImage() and using those (instead of the current mouse location) for the clearRect() in the next sequence. However, now instead of residual draw being shown, residual we have residual clear (erase).
Thoughts on how I can address this?
NOTE: My animation rate is handled using RequestAnimationFrame and not SetInterval().
Assuming your canvas is static during the drag drop operation, a pretty easy way to get a good increase in performance would be to just cache the rendering.
In other words, when a drag drop operation begins, save the current canvas into another one. Stop all rendering except for the one involved with dragging the card. Now, whenever you need to repaint, simply repaint from your copy-canvas. Since you're basically just copying from one to another, it should be pretty fast.
On each processing cycle, you would take the current position of the dragged card, fill that with data from the copy, then redraw the dragged card in the new position.
Other approaches you could try would be to use some kind of a placeholder for the drag. For example, consider using a same-sized DIV which you display while dragging. This should have the benefit of not requiring to touch the canvas while dragging and thus also run a better performance for it.
I'm trying to find a clean way to "move the camera" of a canvas element.
This for my prototype game (side scroller). I'd love to think there's a better solution than moving the whole set of nodes to simulate a "camera" moving around.
Am almost certain to have read a simple how-to (using offsets?) but the fact I don't find anything like that starts to raise doubts... have I imagined reading that!?
Thanks to help me clarify...
J
Presumably you redraw your whole game scene 30 times a second (more or less)
You need to redraw your whole game scene but first translate the Canvas context by some offset.
context.translate(x,y) is precisely what you want. You'll want to read up on the use of that as well as the save() and restore() methods.
When you translate the context, everything drawn afterwards is shifted by that amount.
So you constantly draw something (maybe an enemy) at 50,50 using drawImage(badguy,50,50). Then the player moves, which changes the x of translate to -1 (because the player is moving to the right) instead of 0. You still draw the enemy sprite with the command drawImage(badguy,50,50), but when you draw it the enemy shows up as if it were at 49,50 because of the context.translate(-1,0) command shifting everything before its drawn.
Of course when you get into performance you'll want to be making sure that you are only ever drawing things that can actually be seen on the screen! If your are far down the level with context.translate(-2000,0), you dont want to be drawing objects at 50,50 anymore, only ones that intersect the viewable area.