Currently in a top down game I am developing, I want the player to always be in the center of the screen.
To accomplish this, I am just moving the background down when I want the player to move up, and vice versa.
However, now that I am adding enemies and other objects into the game, I want to avoid the movement getting all wonky when the map moves behind them while they are trying to move also.
Is there any way I can move what the JFrame is viewing up, without changing the coordinates of the background image?
For a better explanation of what I am trying to accomplish, look at the drawing below.
Is what I am trying to accomplish too complicated? Is there an easier way to do this?
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I am creating a game on java, and I would like to reset the whole canvas after painting on the screen. I would like to do this by adding a button on the side of the game, but I am not sure where to add this in my code. The general format of the code is SandLab.java. Would anyone know what area to implement this in?
I wanted to ask if you can use box2d lights so you can see only objects that are in the lights area. For example i have a flashlight and only want to see game objects in the light. I managed to do something like this but the problem is that the sprites of the game objects lose their color intensity because I render lights on top of sprites and the game itself doesn't look good because of this (even though it is the effect that i want).I used box2d bodies with user data containing sprites. I can't figure any way out. Is there any proper way to use box2d lights library to make these objects visible and with their real color? (I am setting lights to X-rays to do this; also I am using it with libgdx in java).
It may be because the default setting is to not use diffuseLight. You have to set rayHandler.useDiffuseLight(true).
Libgdx and Box2DLights - too bright + colors grayed out
imagine that, an imaginary minecraft, where you build cubes.
You have a panel where you have the diferents cubes(tool box),
and other big panel, the world where you build, but the world is bigger.
and all of this things are in the same screen, imagine how can i put a orthografic camera that only zoom the panel where you have the whole world, that it allows you to zoom and build cubes with details and presicion, but the tool box panel still the same position. always visible. ?
Use two cameras. One for the "game" and one for the "HUD".
During a render call, use one camera to render the game, then "switch" cameras and then render the HUD. How you switch cameras depends on what API you're using to render objects (for example use setProjectionMatrix on a SpriteBatch).
You could also create more than one SpriteBatch or more than one Stage (as each tracks camera state internally), but they're a bit heavy-weight.
Beware that when switching contexts, you will probably have to explicitly end/flush/complete the first context before starting the second.
You do not use one Camera to show the stuff. For example you use a Camera for the background of your game and you have a second camera for the game Hud that always has a fixed size. But the game in background can be zoomed in and out because its an different camera.
But for simple boxes on the screen you do not use a second camera. You just use one more Stage that get displayed or not where the new "ui" stuff is shown.
Hope this helps a bit.
I have tried to use different methods but to no avail. So I come looking for a fresh point of view.
I want to have a sprite follow the touch coordinates of the user. So if they dragged their finger across the screen the sprite would move or tween towards the touch coordinates but continuously update to 'follow' the users finger. If the user stopped moving their finger, the sprite would eventually come to a stop at the final touch coordinates.
I can get the sprite to move and tween to a single set of coordinates but not continuously update to follow along. This is for an android game. its in java. this is one of the basic functions i need to use so im not too far along. that being said I can accept direction for open gl or for canvas.
Any help or direction would be much appreciated. thank you!
On every frame, do
Pos = (Pos * 0.95) + (LastTouch * 0.05);
Adjust the ratios until it feels right. Just make sure they add up to 1.
I'm trying to draw a 2D contour plot of some data on Android and I'm wondering what the best approach would be to draw those. The whole datasets can be relatively large (2k * 2k points) and zooming and moving inside the plot should be very fast. Most of the time only a small part of the data will be drawn as the user has zoomed in on the data.
My idea now would be to draw the whole plot onto a large canvas, but clip it to the portion visible on the screen, so that only that part would be really drawn in the end. I find the 2D drawing API of Android somewhat confusing and I'm not sure if this is really a feasible approach and how I would then go about executing it.
So my questions are:
Is it a good idea to draw onto a canvas much larger than the screen and use clipping to display only the relevant part?
How would I create a larger canvas and how would I select which parts should be drawn?
You should start the other way around. Instead of creating a huge canvas you should detect what part of your plot you need to draw and draw only that.
So basically you need some navigation/scrolling and you need to keep the offset from the starting point in memory to calculate where you are. Using the offset you can easily zoom in and out because you just need to scale the plot to the screen.
Is it a good idea to draw onto a
canvas much larger than the screen and
use clipping to display only the
relevant part?
A better question might be, do you have any other options. Some might argue that this is a bad idea since your going to keep memory in use when it isn't relevant to whats happening on the UI. However, from my experiences with the Canvas, I think you'll find this should work out just fine. Now, if you are trying to keep "5 square miles" of canvas in memory your definitely going to have to find a better way to manage it.
How would I create a larger canvas and
how would I select which parts should
be drawn?
I would expect that you will be creating your own "scrolling" method when the user touches the screen via overriding the onTouchEvent method. Basically your going to need to keep track of a starting point X and Y and just track that value as you move the Canvas on screen. In order to move the Canvas there are a number of built in's like translate and scale that you can use to both move the Canvas in X and Y as well as scale it when the user zooms in or out.
I don't think that is a good idea to draw your 2D contour plot on a big bitmap because you need a vector type graphics to zoom in and out in order to keep it sharp. Only pictures are good to scale down but graphs will lose thin lines or come out deformed when scaled down in bitmaps.
The proper way is to do it all mathematically and to calculate which part of the graph should be drawn for required position and zoom. Using anti_alias paint for lines and text, the graph would always come out sharp and good...
When the user zooms out, some items should not be drawn as they could not fit into the screen or would clutter it. So the graph would be always optimised for the zoom level...