I'm not familiar with app development so I want to gain a better understanding on how animations are implemented in apps as I have different ideas.
I have designed 4 images using Adobe Illustrator, 3 of the images are planets and 1 image is a rocket. In my app I would like the rocket to randomly move to a planet when clicking a button, the ideas I have to implement this are:
Programatically move the rocket pixel by pixel towards the randomly selected planet
Or
Create 3 different animations of the rocket moving to each planet and when the random planet has been selected play the correct rocket animation.
Which one is the best approach for what I am trying to achieve? If you have better please can you share as I do not know how to go about doing this.
Thanks!
It's a trade off between download size / performance / versatility / maintainability / implementation time.
Will use more processor, result in a smaller program size, be more versatile (you could allow the user to control the rocket and detect when they arrive at a target planet)
Will use less processor, be simpler to implement, result in a larger program size. You'd need to remake the animations in the case of adding a new planet, doesn't scale well (What happens when you have 20 planets? with different screen resolutions?)
Related
So I'm trying to learn unity by creating simple game which all its does is ball bounces around the screen boundary and collect small white squares. (game looks like this)
However, I noticed game will create black bars on the side outside of the reference ratio that I started my project. (creates black bars)
I looked for solutions online which came down to
Extend my game background (Same concept as creating black bars, right?)
Create script that basically streches the black screen area(where ball bounces around) on my game.
I wanted to avoid create empty space for my game so I avoided solution 1 but solution 2 didn't seem appropriate as well since if I adjust the wall ratio depending on device some players will larger area to travel to collect white squares, which will ruin the balance between devices.
What would be the ideal way for my game without hurting the balance? The option for this would be but black bar seems way too thick.
It seems that you have already covered most of the cases yourself.
When creating a game you will usually have a "world" which has its own coordinate system. In your case you may have a 2D space with certain width and height in which your ball is moving. The size of the space can be defined any way you want to; for instance you can define that your ball is always of size 1 and the world size can than be determined based on the level selected.
The reason I am writing this is to keep in mind that maybe you wish to keep your options open to later change the size of your world and an option to have the world size different based on selected level.
It is possible to determine world size based on device size as well but that means (as you already mentioned) that your world changes based on device used which means that gameplay will not be consistent across devices.
What you are facing is a pretty standard issue among all games. I for instance remember Diablo discussing an issue with wide-screen users where monsters on far edges would not respond to player and would stay idle instead of attacking due to game mechanic expecting to react when user got "closer".
Anyway. You need to decide how you wish to show your world to the user. In your case you seem to be leaning toward a few rules:
You wish to show all of the world at the same time
You wish to use as much space as possible
This sounds similar to showing an image with preserve-aspect-fit mode. So yes, you will need some borders around devices that have different aspect ratio then your world.
Another option is to use "fill" approach and your content would automatically scroll based on the movement (of your ball). Not sure if this is applicable to your game though.
Yet another way is to define that only X distance around player (ball) is always shown and your ball is always centered.
But in general it usually comes down to having some "empty" solid area. One reason may be aspect ratio but another may be newer devices (iOS specifically) will have rounded corners and other dead areas for camera and speakers. You will want to avoid those areas but still want to draw "something" there like a solid wall.
I'm making a War Game for iOS using Monotouch and C#. I'm running into some problem with the audio sound effects.
Here's what I require: The ability to play many sound effects simultaneously (possibly up to 10-20 at once) and the ability to adjust volume (for example, if the user zooms in on the battlefield the gun shot volume gets louder).
Here are my problems:
With AVAudioPlayer, I can adjust volume but I can only play 1 sound per thread. So if I want to play multiple sounds I have to have dozens and dozens of threads going just incase they overlap... This is a war game, picture 20 soldiers on the battlefield. Each soldier would have a "sound thread" to play gun fire sounds when they shoot because It is possible that every soldier could just happen to fire at the same exact time. I don't have a problem with making lots of threads, but my game already has dozens of threads running all the time and adding dozens more could get me into trouble... right? So I'd rather not go this road of adding dozens of more threads unless i have too...
With SystemSound, I can play as many sounds as I want in the same thread, but I can't adjust the volume.... So my work around here is, for every sound effect i have - save it like 4 times at 4 different volumes. That is a big pain... Any way to adjust volume with SystemSounds??
Both of these answer some of my requirements, but neither seems to be a seamless fit. Should I just go the AVAudioPlayer multi-threading nightmare road? Or the SystemSound multi-file-with-different-volume-levels nightmare road? Or is there a better way to do this?
Thanks in advance.
Finally found the solution to my problem. AVAudioPlayer IS capable of playiing multiple sounds at once but only with certain file formats... The details are available in this link. The reason why I couldn't play my sound effects simultaneously was because the file format was compressed and the iphone only has 1 hardware decompressor.
http://brainwashinc.wordpress.com/2009/08/14/iphone-playing-2-sounds-at-once/
I'm trying to implement a simple game - I've written a dial control but having trouble writing a on-screen thumbstick in Silverlight for Windows Phone - this would be a large circle - say 150px wide with a 25px circle which when held down moves round the centre much like a real thumbstick - like the Xbox 360 controller thumbsticks.
I'm finding creating this a little tricky - if there are any examples such as a Joystick one I can shrink down for example? Been trying to create something for ages and can't seem to figure it out - the centre circle is loaded from an Image and the Larger one too so it can be customised - getting the two to be within each other centred is the easy part!
As discussed, i'd suggest using XNA doing it since its considerably easier to do. With Mango you could combine XNA and Silverlight and therefore satisfy your needs for some Silverlight too.
Look at this example:
http://create.msdn.com/en-US/sample/touchthumbsticks
It shows how to easily create a thumbstick control. To restrict the area which you can touch, just create a new Rectangle at the position of the thumbstick with the size you desire and use the .Contains(...) overload to check if the position of the tap is inside it and then act accordingly (update the stick, or ignore input).
Check out the .Contains(...) function and its overloads:
http://msdn.microsoft.com/de-de/library/microsoft.xna.framework.rectangle.contains.aspx
I have learned that many programmers tend to stick to Silverlight for they think XNA is some kind of holy grail and is complex to program. It is not. It just needs a bit of getting used to, but you will surely enjoy the ride to XNA enlightment. I can tell, i did :) It's fun! Just trust a stranger on the internet!
If you need to stick to Silverlight and Pre-Mango, i fear i can offer nothing of value for you, and i fear you will suffer pain in trying to recreate the same functionality XNA already offers programmers for no charge.
I am using XNA to develop a game which requires both sound effects and music. I'm trying to figure out how to implement the sound engine. Microsoft provides the ability to use the Content Pipeline to load and play audio. However, I also seen people use Xact to do the same thing. My question is, whats the difference and what would be the better approach to making a sound engine?
Xact is feature rich but complex to use. It was originally the only way to play sound but people wanted something simpler so Microsoft added the content pipeline method.
Use the Content Pipeline if you want:
To play a sound (2d or 3d)
To not have to invest a lot of time
learning an audio framework
Use Xact if you want:
Categories of sounds that can be
interdependently controlled, like
mute game sounds but not menu sounds
Real time advanced control over sound
pitch, volume. For things like
turrets spinning up, cars
accelerating etc.
To have multiple varieties of a
single sound effect like a seven
different pain sounds and have Xact
choose which one to play.
To have a sound play with slightly
different pitch, volume, filter or 3d
pan every time it is played. This is
really good for bullets and
repetitive things like that. There
is nothing that says fake computer
simulation like a repeating sound
with no variance.
To allow a game designer or sound
designer full control to edit and
change sounds without touching the
code.
To have sound banks (collections of
sound) that you can load or unload as
a group, which can use different
compression settings and can be in
memory or streaming.
To mix the volume, pitch and priority
of sounds in an editor.
To apply filtering to a sound.
To control whether the sound is
looping or not.
To use DSP Effects
One of my favourite things about Xact is editing and previewing of sound functions in editor. For example a volume fade on a turret overheat sound. With XACT you can sit down with the sound designer, even if he's not a technical guy and edit the control curves until he's happy with the sound. Once you've set it up it's really easy to change later on. In this example image here a turret is overheated. At the end of the overheat cycle the hissing steam noise volume is reduced, but because it's a curve I have a lot of control over how the sound fades out. I've used this with a beam weapon as well, dropping the frequency according to a curve as it runs out of ammo.
I recently joined a project where I need to get some vehicle based computer vision system. So what sort of special functionalities does a camera need, to be able to capture images while traveling at varying speeds ? for example how high a frame rate is required, and the exposure duration, shutter speed? Do you think that webcams(even if high end) will be able to achieve it ? The project requires the camera to be programmable in C# ...
Thank you very much in advance!
Unless video is capable of producing high quality low blur images, I would go with a camera with really fast shutterspeed, very short exposure duration, and for frame rate, following Seth's math, 44 centimeters is roughly a little more than a foot, which should be decent for calculations.
Reaction time for a human to respond to someone hitting the breaks in front of them is 1.5 seconds. If you can determine they hit their break light within 1/30th of a second, and it takes you 1 second to calculate and apply breaks, you already beat a human in reaction time.
How fast your shutter speed needs to be, is based on how fast you're vehicle is moving. Shutter speed reduces motion blur for a more accurate picture to analyze.
Try different speeds (if you can get a camera with this value configurable, might help).
I'm not sure that's an answerable question. It sounds like the sort of thing that the Darpa Grand Challenge hopes to determine :)
With regard to frame rate: If you're vehicle is going 30 miles per hour, a 30 FPS web cam will capture one frame for every 44 centimeters the vehicle travels. Whether or not that's "enough" depends on what you're planning to do with the image.
Not sure about the out-of-the-box C# programability, but a specific web-cam style camera to consider would be the PS3 eye.
It was specially engineered for motion-capture and (as I understand it) is capable of higher-quality images a high framerates than the majority of the competition. Windows drivers are available for it, and that opens the door for creating a C# wrapper.
Here is the product page, note the 120fps upper-end spec (not sure that the Windows drivers run at this rate, but obviously the hardware is capable of it).
One Note on shutter speed... images taken at a high framerate in low-light will likely be underexposed and unusable. If you'll need this to work in varying light conditions then the framerate will likely either need to be fixed at the low-end of your acceptable range, or will need to self-adjust based on available light.
These guys: Mobileye - develop such commercial systems for lane departure warnings and vehicle and pedestrian detection.
If you go to the "Manufacturer Products->Development and Evaluation Platforms->Cameras"
You can see what they use as cameras and also for their processing platforms.
30 fps should be sufficient for the applications mentioned above.
If money isn't an issue, take a look at cameras from companies like Opeton and others. You can control every aspect of every image capture including: capture time, image size, ++.
My iPhone can take pictures out the side of a car that are fairly blur free... past 10-20 feet. Inside of that, things are simply moving too fast; the shutter speed would need to be higher to not blur that.
Start with a middle-of-the-road webcamera, and move up as necessary? A laptop and a ride in your car while capturing still images would probably give you an idea of how well it works.