I'm trying to make an image more interactive by adding gestures (currently I'm thinking about only zoom, might add later depending on the requirement). It's a parking app by the way.
By interactive I mean that user can tap on a part of an image, let's say it's area A and labelled "A", and then a new interactive image will pop up for that area.
I'm pondering whether I should break down the image part by part in order to detect user's tapping location, or should I take the X, and Y coordinate? And if I should take the coordinate, does that mean I have to alter the code so that it'll cover different screen sizes?
Another question is.. I'm thinking of using Djikstra's algorithm for best route to be taken by user, does the algorithm need the image to be whole?
I'm also planning to add marks for vacant and occupied slots, but it is trivial for whether I should split the image to parts or not, right?
Related
I am currently developing an Android app which allows the user to plot a graph by hand drawing on a canvas. Now I want to make sure that the graph consists of only one path. Is there a way to implement an object that lays on the canvas (for example a mouse or whatever) which can be controlled by the user in order to sketch the graph?
So the user should touch the object and move it. If he wants to extend the path, he just can touch it again and proceed.
Sorry if it's not clear what I want to achieve, the screenshots may help.
Screenshot 1 shows, which type of graphs I want to avoid, while the second screenshot shows how the graphs should look like (don't consider the green circles, they're just indicating turning points)
I'm creating an Android board game with several differently shaped board spaces (like Risk).
I want to be sure that my board appears correct and that OnTouchListeners stay in place on the GUI regardless of screen size/resolution.
Possible solutions I have thought of and their problems:
Create a single image for the board and assign OnTouchListeners based upon pixel geometry. Problem: If the user's display is a different resolution, my Listener might not be under the same pixels as my image (right?)
Create several ImageButtons and arrange them together. Problem: the ImageButtons might get rearranged based upon the display and I would end up with overlapping spaces or gaps.
Use Android custom drawing. If I do this, how would I link my Listeners to my Canvas and be sure that they are synced?
Basic question:
How to be sure that listeners sync with graphics in a GUI that uses irregular geometry?
I worked on an app with irregular touch areas so I can give you guidance on one way to achieve this.
Start with a single image for your entire board. This image is going to have a certain ("intrinsic") width and height regardless of any device resolutions.
Now here comes the tedious part. You (or maybe your graphic designer) will need to plot out coordinates of an irregular polygon for each touch area. These will be constants to your application.
When you are displaying your board, if you are zooming and panning on the image, you want to keep track of the transform matrix for the display. When the user touches the screen, you will get x,y coordinates from OnTouchListener and for those to be useful, you will have to "de-transform" the x,y to normalize it against the intrinsic dimensions of the board and your polygons.
We rolled our own hit-testing logic using an algorithm from http://alienryderflex.com/polygon/, but you can also try this: Create a Path out of your polygon coordinates (using moveTo(), lineTo(), and close()), then assign the Path to a Region using Region.setPath(). Once you have that, supposedly you should be able to hit-test using Region.contains(x,y), but I've never tried it so I can't guarantee that's going to work.
I'd like to create a custom map. It should be or look like one picture, but according to the part of which the user clicks, it should move the user to a different location (i.e. start a different activity). I've seen it done in several games but I don't know how to do it myself.
The part of the picture should have non-geometrical borders (obviously it would be easily done with many square images). Sadly, I don't even know what term describes what I want to do so I wasn't able to find any helpful tutorials or discussed topics.
Example:
Picture: http://i236.photobucket.com/albums/ff40/iathen/mapEx.png
If the user touches the purple slide, (s)he should be leaded to activity_1
If the user touches the blue slide, (s)he should be leaded to activity_2
If the user touches the green slide, (s)he should be leaded to activity_3
In my experience there are 2 main (most used) ways to achieve this.
The first (my favorite):
Get the data from a PNG
You should write multiple layers to a canvas. These layers constitute your "zones" (blue, green, purple in the image). To obtain the data of these areas, you get it from PNGs (with transparencies off course) to write the canvas with whatever you want. You must store the values where there can be a tap from the user (non-transparent areas). Notice that this values can be scaled up/down depending on the map size, screen resolution, map dimensions, etc.
Once you've written the layers to the canvas you should check for a match of the user tap and the stored areas you have. You should take into consideration here the order in which the user tap is processed in your code. For instance, in your image, the purple layer is on top so it must be processed first, the blue as second, and the green as the last one. This way you can have an "island" inside a bigger area.
The second way:
Generate the boundaries programmaticaly
I think this solution is self-explanatory. The only I've faced with this variant is that when the surfaces boundaries get messy, it's really complicated to generate the proper equations.
EDIT:
Using the first approach you can employ multiple PNGs to load data or use a single PNG with data coded into the bytes (i.e. RGB values). It's up to you to decide which one to implement.
Hope it helps!
Since a touchscreen itself isn't very accurate, your collision detection for the buttons doesn't need to be either. It would be a waste of time to try to make a complicated collision detection algorithm to detect a touch within those weird shapes.
Since you are making a game, I assume you know how to handle custom touch events, as well as canvas (at least). There are many ways to do what you want, but in the specific example image you linked is kind of a special case.
You could create a giant bounding circle around the three blobs, and then check if the user touched within the bounds of the circle (ie check if the distance from the touch to the center of the circle is less than or equal to the radius). Once you determine that it is, you could check which section of the circle it falls into by splitting it up into 3 equal sections. Requires some math, but shouldn't be that complicated.
It wouldn't be a perfect solution, but it should be good enough. Although, you might have to change the buttons a little so they aren't so stretched out horizontally, otherwise a bounding circle wouldn't be ideal.
Personally, in my games I always have "nodes" that represent the visual elements of the game, such as buttons. Instead of using a large image like you are doing, I would create separate images for each button, and then check their collisions with touch events independently. That way I could have each button check with their own individual bounding circles, or, if absolutely necessary, I could even have custom algorithms for each individual button.
These aren't perfect solutions. If you do want a pixel-perfect solution, you'll need to implement some polygon collision detection algorithms
One thing to consider is screen size and ratio. The only constants you should use are for percentages.
I don't know how to explain this.
But take Android desktop as an example.
When you move your finger, you move the whole desktop, until a point that you're on the next desktop. So as you can see, if you move the screen, for about 51% to the right, when you leave your finger off the screen, it will go to the right screen, and if you just moved the screen 40ish percent, it will be back on the same screen.
How is this pattern called?
Some sort of "predicting" users movements.
Maybe you are talking about the Location Within pattern:
Problem:
You must describe the location within a series of screens which
contain alternate views, or which continue the display of a set of
content.
Solution:
When several screens of similar or continuous information are
presented with an organic access method, an indicator is usually
required so the user understands their position within the system.
Other sources might call such a thing "carousel" or "slideshow".
Updated answer:
After reading more carefully, "Location Within" might only reference the page position indicators that show which screen is currently in view. Perhaps just the Slideshow or Film Strip patterns describe more exactly what you mean.
As FoamyGuy pointed out in a comment, ViewPager is the way to implement "slideshows" in Android.
Additionally, ViewPagerIndicator provides flexible options to display the page position indicators ("Location Within" pattern)
I have received requirement like this http://www.youtube.com/watch?v=7MYQicokwmY&feature=plcp I am reviewing this requirement.As per requirement we have to build touch detection like in video link for Android enabled Tablets.
In that video toys (toys with circular, star or rectangle shape) uses Conductive Silicone Sensors with that they are detecting touch on screen & deciding shape of external world object like triangle,circle or a star & further processing the shape.
I have to use same touch detection for android tablets.Can anybody help me to find the way to implement this on Android platform ? Is there any API or framework to implement it?
If you see the video around 1:13, they show what I am guessing are some prototypes, the circle has three points, the hexagon too...
My best guess is that the biggest part of the object is non-conductive and only has a few points that are conductive and would actually register as touch points on the screen. The key is that each of them will be different enough that you would be able to recognize them no matter what the orientation is, what the position (and depending on your requirements whether you have several of those objects at the same time on the screen).
You can also play with the area of each conductive points so in your code, you will get the touch information, you can get different pressure values from the MotionEvent
Now how you place the conductive points and how many on each shape is completely up to you and would really depend on what your requirements are (recognizing arbitrary shape is not an option...)
Most touch screens would reject the touch if the area is too large (that's palm rejection), so I don't think there are much other ways to do this...