I've built an game in Libgdx which uses a single FitViewport passed-in to some Screens (Splash/Intro/Game/Menu/Pause etc.).
Each Screen has it's own Stage containing Groups of Actors - I've written a custom render loop to allow Screens to fade-in/out or slide around or render behind each-other - that's all great.
I now want a 'UI' screen which will rotate on smartphones to match their orientation (everything else in the game will NOT rotate).
I can make this work visually by using a TransformMatrix on the SpriteBatch but that doesn't affect the Stage's 'touch' detection (or debugdraw) and it seems there is no way to do this within the Stage (localtoparentcoords allows for rotation and scale but NOT transformation)
Bear in mind that it will not be 'square' (the FitViewport enforces 16x9 ratio) so it needs translation as well as rotation...
Note: I've tried to mess around with cameras but that's the wrong paradigm - cameras are a different view of the same thing - I want different things (transformation and rotated) drawn into the same view!
Note also: I've already started to create my own version of a Screen/Stage class to do this - I think it might be quicker than kicking the existing code into working properly but I'll be surprised if I'm the first person to want this?
I think I've sort-of solved this by stepping-back a bit and looking at how the Stage/Actor system works.
The idea of rotating AND transforming an entire Stage is fraught with complexity - that I could do it at the SpriteBatch level was a distraction which led to a lot of wasted time - sadly.
It was only when I realised that as I was calculating the position of all my UI (Actor) elements relative to either the screen center or a corner, I may as well take the further step of rotating and transforming them at the same time! I also realised that Grouping them ,made this very simple (indeed I could have static and rotating elements simply by using 2 separate Groups!)
Rotating/Moving an Actor will, of course, adjust it's bounding box/touch-area as well - so I now have a proper Stage/Group/Actor model which rotates as the device is rotated - I could be just static information (scores) or even a dynamic menu or an overlay for a 'cue' in a pool game or whatever...
As Edison would have said - I didn't waste 2 days, I just spent 2 days coming up with a large number of ideas which I now know not to work!
Related
I am working on a map application and I have come across an issue with how my tiles are laying while scaling.
Here is a basic look at my structure:
There is obviously a lot more going on, but you get the idea. Now, I scale the Map App Sprite to zoom in. When that scaling occurs, there is a gap between each tile.
You can see the gap where 4 tiles meet here:
I am caching everything as a bitmap. For each Layer (which all extend Bitmap), I have smoothing set to true and pixelSnapping set to PixelSnapping.ALWAYS (pixel snapping shouldn't help here, but it shouldn't hurt either).
Does anyone have any suggestions on how to fix this issue?
(For the sake of completeness, the Map app is built entirely using AS3 and it is embedded in a Flex app)
Using integers for tile x,y locations and calculating those locations correctly is most likely the fix here, unless the images have seams in them!
The code that calculates and sets the x,y locations would be needed to properly pinpoint the issue in the code.
But, also if you are scaling that container sprite, you would want to ensure that you scale so that the width/height of a tile is an integer value.
For example, if you scale your sprite that contains these tiles, the widths/heights of the individual tiles might not always be integers, therefore creating those seams you see.
What you could do in that case is do your scaling by adjusting your width/height values by integer values, taking into account proportions, as opposed to using scaleX and scaleY on your container sprite.
Without seeing your code it's difficult to be sure, but it is possibly just a visual artifact due to scaling - eg: a 250px wide bitmap scaled to 155% should be rendered at 387.5px wide but thats impossible so its rendered at 388px wide - with the 0.5px part rendered as 1px at 50% alpha to give 'appearance' of 0.5px.
Ensuring scaled bitmaps widths/heights are always integers may solve it?
This looks like a rounding error.
Without code it's hard to know: it would be a great asset to you and us if posted a barebones example of your tiling class. In the process of subtraction you may very well discover your solution.
I'd offer that you should test what happens when you scale and algin four 100x100 bitmap images at various fine grain steps, to detect if it's a Flash rendering issue or a defect in your class.
I've got a problem in actionscript3 with moving large DisplayObject-s. When the size of the DisplayObject is quite large (more than screen size) the movement loses smoothness and it looks like the object starts jumping forward and backward, which overall looks very unpleasant.
Does anybody know the way to fix that? I am trying to make a sort of a race game, where I need to move the background sprite to make the illusion of movement.
Try turning on cacheAsBitmap. That may give you some performance improvements, especially if the object is static (doesn't have any animated bits in it). With AS3 and Flash Player 10 or newer you should be able to get smooth movement even with a large sprite. I've got several games that do it.
Have to agree with Laurent - it is probably better to split the background into small pieces and move them
I am starting to get a grasp of the HTML canvas and I wanted to know if it is encouraged to use optimization techniques. In games for example, is it encouraged to use bounding boxes and only redraw the portion of the screen that needs redrawing, or do people just blindly redraw everything. I ask this b/c I am creating a new engine for canvas and imposing bounding boxes complicates things greatly (ie. the user no longer has the freedom to quickly draw things to the stage).
Absolutely, it's almost always better to draw only what has changed on the screen at any one time. Attempting to draw everything causes unnecessary rasterisation of the images being drawn into one output image, when it's not even going to change on the screen.
In a small game I made a year ago, I was drawing a 2D array of tiles on the screen and getting around 15 frames per second. When I changed it to draw only the tiles visible on the screen, it was an amazing improvement. It will improve in this circumstance too.
I'm new to programming games, so I'll make it short and sweet:
Is there any standard practice for Flash/AS3 for organizing sets of game Sprites, especially related to movement. For Example, if I am moving left, and then down, there should be a fill in animation...if we want that fill-in animation, do we need to create an animation for every permutation of all 8 directions our character can move? Also, if we want to have dynamic shadows for our 2d sprites, do we have to draw a light source for every one of those 8 directions for all 8 directions?
No, there is no practice like that.
However, here are some tips from my personal experience:
fill-ins:
if your sprite is small, just don't do any
other - SOME filling - for example, just from one direction to the one near it, and whenever the sprite rotates more than just on direction, play the fill-ins in a row
if you want to make ALL fill-ins, that would be a lot of work, I would say too much for something as small as a fill-in between two directions - better spend the time for something else
light sources:
again, matters HOW visible this sprite will be - if it is something very small, just mirror and / or don't make any lighting at all
other - I am used to always make one sprite (fully redrawn, or just light redrawn - does not mater) - for all directions - it adds a nice touch to visible things like player sprite that are always going to be on the screen
I'm creating a space game in actionscript/flex 3 (flash). The world is infinitely big, because there are no maps. For this to work I need to dynamically (programatically) render the background, which has to look like open space.
To make the world feel real and to make certain places look different than others, I must be able to add filters such as colour differences and maybe even a misty kind of transformation - these would then be randomly added and changed.
The player is able to "scroll" the "map" by flying to the sides of the screen, so that a certain part of the world is only visible at once but the player is able to go anywhere. The scrolling works by moving all objects except for the player in the opposite direction, making it look like it was the player that moved into that direction. The background also needs to be moved, but has to be different on the new discovered terrain (dynamically created).
Now my question is how I would do something like this, what kind of things do I need to use and how do I implement them? Performance also needs to be taken into account, as many more objects will be in the game.
You should only have views for objects that are within the visible area. You might want to use a quad tree for that.
The background should maybe be composed of a set of tiles, that you can repeat more or less randomly (do you really need a background, actually? wouldn't having some particles be enough?). Use the same technique here you use for the objects.
So in the end, you wind up having a model for objects and tiles or particles (that you would generate in the beginning). This way, you will only add a few floats (you can achieve additional performance, if you do not calculate positions of objects, that are FAR away. The quad tree should help you with that, but I think this shouldn't be necessary) If an object having a view leaves the stage, free the view, and use the quad tree to check, if new objects appear.
If you use a lot of objects/particles, consider using an object pool. If objects only move, and are not rotated/scaled, consider using DisplayObject::cacheAsBitmap.