XNA DrawableGameComponent mouse input problem - xna

I'm developing a simple board game, where my game board is represented as a DrawableGameComponent. In the update method of board I'm checking mouse input to determine which field on the board was clicked. The problem I'm encountering is that mouse click gets registered only once every 5-6 clicks.
Mouse click code is basic:
public override void Update(GameTime gameTime)
{
MouseState mouseState = Mouse.GetState();
Point mouseCell = new Point(-1, -1);
if (mouseState.LeftButton == ButtonState.Pressed && previousMouseState.LeftButton == ButtonState.Released)
{
mouseCell = new Point(mouseState.X, mouseState.Y);
}
// cell calc ...
previousMouseState = mouseState;
base.Update(gameTime);
}
In the Game.cs, I'm just adding my board to Components collection.
Has anyone idea what I might be missing here?
EDIT: Actually, it's not just the mouse, keyboard input doesn't work properly either, so I've probably messed up DrawableGameComponent implementation altrough I have no idea how.
EDIT2: Found some folks here: http://forums.create.msdn.com/forums/p/23752/128804.aspx and here: http://forums.create.msdn.com/forums/t/71524.aspx having very similar problems.
After unsuccessful debugging I ditched the DrawableGameComponent and implemented manual LoadContent/Update/Draw calls and put all input collecting into game.cs. Works like a charm.
However, if someone has any explanation what could have went wrong (looks like DrawableGameComponent somehow clodges input) I'd really like to know.

The problem is, that if the mouse changes state between MouseState mouseState = Mouse.GetState(); and previousMouseState = mouseState;, then previousMouseState and mouseState will have the same value.
This can be maked almost imposible by moving those to lines as close to each other as posible.
public override void Update(GameTime gameTime)
{
Point mouseCell = new Point(-1, -1); //moved this up, so that the mouseState and previousMouseState are as close to each other as possible.
MouseState mouseState = Mouse.GetState();
if (mouseState.LeftButton == ButtonState.Pressed && previousMouseState.LeftButton == ButtonState.Released)
{
mouseCell = new Point(mouseState.X, mouseState.Y);
}
//It is almost imposible, that the mouse has changed state before this point
previousMouseState = mouseState; //The earliest place you can possibly place this line...
// cell calc ...
base.Update(gameTime);
}

Related

Xamarin SpriteKit running action with key

I am using SpriteKit with Xamarin. I'm currently making a game similar to flappy bird, except the pipes can also 'chomp' down and kill you like that. So at any given time my pipe sprites can be running two actions, one for movement along the X axis (when the player is moving) and one for movement along the Y axis (closing the pipes). When the player stops moving along the X axis I want to stop the running action of the pipes that moves them horizontally, but still keep the chomping action going. I'm having trouble setting up a key for my action though. Currently, this is what I have.
public override void TouchesEnded (NSSet touches, UIEvent evt)
{
base.TouchesEnded (touches, evt);
//TODO: Optimize by removing action by key instead of all of them. Figure out how to do this and impliment.
//This needs to be done before refining chomp as it will flow into the chomp logic
//by not stopping a chomp mid-way because the player lifted their finger.
poletop.RemoveAllActions();
polebottom.RemoveAllActions();
pole2top.RemoveAllActions ();
pole2bottom.RemoveAllActions ();
background.RemoveAllActions ();
//restarting the chomping action if it was stopped before.
chomped_return (false);
chomped_return (true);
}
So I'm basically stopping all actions, then restarting only the chomp if it was running (gets restarted in chomped_return).
This isn't very efficient and also causes some lag in-game as it stops and starts.
Code for starting the action along the X axis (player movement). This is the SKAction that I want to have the key so I can stop it and it alone. resetpoles is the completion function.
SKAction movebottompole;
SKAction movetoppole;
movebottompole = SKAction.MoveToX (edgebottom.X, flTime);
movetoppole = SKAction.MoveToX (edgetop.X, flTime);
polebottom.RunAction (movebottompole, resetpoles);
poletop.RunAction(movetoppole, resetpoles);
Chomping down on the player is an instant teleport of the pipes, but here's the code that runs to start the action of the pipes returning to their original position along the Y axis. This is setting up the action that I don't want to stop until it has completed.
public void chomped_return(bool blFirstPole)
{
//define our two actions
SKAction topreturn;
SKAction botreturn;
//define our floats for the time calculation
float flTime = 0;
float flMoveSpeed = 750;
float flDistance = 0.0f;
if (blFirstPole == true)
{
flDistance = (float)polebottom.Position.Y;
}
else if (blFirstPole == false)
{
flDistance = (float)pole2bottom.Position.Y;
}
//calculate time based on distance and vector units/second desired.
flTime = flDistance / flMoveSpeed;
//setup our moveto actions and use the time calculated above. Start the action.
topreturn = SKAction.MoveToY (750.0f, flTime);
botreturn = SKAction.MoveToY (0.0f, flTime);
if (blFirstPole == true)
{
poletop.RunAction (topreturn);
polebottom.RunAction (botreturn);
}
else if (blFirstPole == false)
{
pole2top.RunAction (topreturn);
pole2bottom.RunAction (botreturn);
}
return;
}
The variable blFirstPole is used to determine whether or not we are running the action on the first set of poles or second set (as there can be two on screen at once)
Would really appreciate any assistance, if you need any more information please do let me know!
Thanks
You can use RemoveActionForKey to remove an action with an certain key.
https://developer.xamarin.com/api/member/MonoTouch.SpriteKit.SKNode.RemoveActionForKey/p/System.String/
polebottom.RunAction(movebottompole, "movebottompole");
// remove it
polebottom.RemoveActionForKey("movebottompole");
But now you don't have your completion handler anymore. You can solve it by combining these two actions into one Sequence.
var poleactionWithCompletion = SKAction.Sequence(movebottompole, restpoles);
polebottom.RunAction(poleactionWithCompletion, "movebottompole");
If you need this more often, you can implement an extension method like:
public static class SKNodeExtension
{
public static void RunAction(this SKNode node, SKAction action, SKAction completion, string key)
{
var sequence = SKAction.Sequence(action, completion);
node.RunAction(sequence, key);
}
}
and then run your action like:
polebottom.RunAction(movebottompole, restpoles, "movebottompole");

Dealing with game cursor, not windows cursor

Earlier, I had an issue with my Windows cursor being uncoordinated with the game and asked here how I could solve this. A member suggested me to hide the Windows cursor and create a custom game cursor, so I did this. However, a new problem occurred.
My game cursor is usually offset to the right of the Windows mouse, so when I want to move the game cursor to the left side of the window and click my left mouse button, it causes a disturbance to the game, such as bringing an application in the background to the top.
Here is a picture of what I mean: http://i.imgur.com/nChwToh.png
As you can see, the game cursor is offset to the right of the Windows cursor, and if I use game cursor to click on something on the left side of the window, the application in the background (Google Chrome in this case), will be brought up to the front, causing disturbance to the game.
Is there anything I can do to use my game cursor without any disturbances?
I have just tried to move everything out of their classes, all into the main Game class.
This fixed the problem, but does not give me an answer to WHY this happens.
The code is exactly the same, it's just organized to separate classes.
So, does anyone know why this is?
Why is using object-oriented programming instead of putting everything in the game class going mess up my mouse coordination and stuff?
Normally, you would have a texture for you in-game cursor where, for instance, the pixel at [16,16] is where you are "aiming" (the center of a crosshair, for instance). What you owuld to to draw this centered on the mouse is to use Mouse.GetState() to get the position, and then offset the drawing of your mouse-texture by the negative of the "center" of the "aim"-point.
so let's say we make a custom Mouse-Class:
public class GameMouse
{
public Vector2 Position = Vector2.Zero;
private Texture2D Texture { get; set; }
private Vector2 CenterPoint = Vector2.Zero;
public MouseState State { get; set; }
public MouseState PreviousState { get; set; }
//Returns true if left button is pressed (true as long as you hold button)
public Boolean LeftDown
{
get { return State.LeftButton == ButtonState.Pressed; }
}
//Returns true if left button has been pressed since last update (only once per click)
public Boolean LeftPressed
{
get { return (State.LeftButton == ButtonState.Pressed) &&
(PreviousState.LeftButton == ButtonState.Released); }
}
//Initialize texture and states.
public GameMouse(Texture2D texture, Vector2 centerPoint)
{
Texture = texture;
CenterPoint = centerPoint;
State = Mouse.GetState();
//Calling Update will set previousstate and update Position.
Update();
}
public void Update()
{
PreviousState = State;
State = Mouse.GetState();
Position.X = State.X;
Position.Y = State.Y;
}
public void Draw(SpriteBatch spriteBatch)
{
spriteBatch.Begin();
spriteBatch.Draw(Texture, Position - CenterPoint, Color.White);
spriteBatch.End();
}
}

Changing Shape on Button Press Action Script 3.0

Alright, sorry if this is a pretty easy question to get answered, but I looked around through pages and pages on google and couldn't find anything somewhat related. I got a lot of help, but I still can't seem to get this part of my ActionScript working. I have a program, that when running, allows me to paint random color squares on mouse click. I added a button, that is supposed to be able to change the shape being painted from rectangle to circle. I can't seem to get that button to work. This is what my code looks like so far.
var color:Number;
stage.addEventListener(MouseEvent.MOUSE_DOWN, startDrawing);
stage.addEventListener(MouseEvent.MOUSE_UP, stopDrawing);
function startDrawing(e:MouseEvent):void {
stage.addEventListener(MouseEvent.MOUSE_MOVE, makeShapes);
color = Math.random() * 0xFFFFFF;
}
function stopDrawing(e:MouseEvent):void {
stage.removeEventListener(MouseEvent.MOUSE_MOVE, makeShapes);
}
function makeShapes(e:MouseEvent):void {
var rect:Rect = new Rect(10,10,color);
addChild(rect);
rect.x = mouseX;
rect.y = mouseY;
}
shape_btn.addEventListener(MouseEvent.MOUSE_DOWN, mouseDownHandler);
function mouseDownHandler(event:MouseEvent):void {
}
At the bottom I left it blank, it seems to be the part I'm stuck on. I've tried simply setting the VAR to my "Ellipse" class I had made, which gets it to work, but only that one time when I click the button. It doesn't stay a circle and allow me to paint with the shape. Again I'm sorry, I felt like I was getting pretty close to the solution, and then I hit a wall.
Hard to understand what the difficulty is, but I'll try to address what I understand.
First, the stage mouse down event will capture your button event, so you might as well get rid of it and stick to one mouse event.
stage.addEventListener(MouseEvent.MOUSE_DOWN, onMouseDown);
private function onMouseDown(ev:Event):void
{
if (ev.target==shape_btn)
changeShape();
else if (ev.target==stage)
startDrawing();
}
Or something along those lines.
Second, I don't know what Rect is. Is it a class you have an access to? This is how I'd do it without a special class:
private function makeShape():void
{
switch (shapeType)
{
case "rect":
drawRect();
break;
case "circle":
drawCircle();
break;
}
}
private function drawRect():void
{
var rect:Shape = new Shape();
rect.graphics.beginFill(color);
rect.graphics.drawRect(0, 0, 10, 10);
rect.x = mouseX;
rect.y = mouseY;
addChild(rect);
}
private function drawCircle():void
{
var circle:Shape = new Shape();
circle.graphics.beginFill(0xff0000);
circle.graphics.drawCircle(0, 0, 10);
circle.x = mouseX;
circle.y = mouseY;
addChild(circle);
}
and finally, the changeShape function:
private function changeShape():void
{
shapeType = shapeType=="rect"?"circle":"rect";
}
There are better ways to go about it, but when dealing with two shape types only this is acceptable.
Of course you need to have a var shapeType:String = "rect" somewhere in your code, outside the functions.
I also think the color randomization should be in the mouse move handler rather than the mouse click. Is that on purpose?

Do screen transitions when the user clicks on a bitmap

I am working on an eBook app where I need to transition the screens from left to right and right to left. I tried many samples that I've found, but I am not successful. How do I change the screen frequently when user clicks on the screen from left to right and right to left. What is the basic idea for transition of pages. I went through the Developer Support Forum thread "page-flip effect" looking for a solution, but I can't see it.
The following code is not logical. In which position do I have to implement flip effect for flipping pages in the screen and how to implement it?
public class TransitionScreen extends FullScreen implements Runnable{
private int angle = 0;
Bitmap fromBmp,toBmp;
public TransitionScreen(){
}
public TransitionScreen(AnimatableScreen from,AnimatableScreen to) {
fromBmp = new Bitmap(Display.getWidth(), Display.getHeight());
toBmp = new Bitmap(Display.getWidth(), Display.getHeight());
Graphics fromGraphics = Graphics.create(fromBmp);
Graphics toGraphics = Graphics.create(toBmp);
Object eventLock = getApplication().getEventLock();
synchronized(eventLock) {
from.drawAnimationBitmap(fromGraphics);
to.drawAnimationBitmap(toGraphics);
// Interpolate myOffset to target
// Set animating = false if myOffset = target
invalidate();
}
try {
synchronized (Application.getEventLock()) {
Ui.getUiEngine().suspendPainting(true);
}
} catch (final Exception ex) {
}
}
protected void paint(Graphics g){
//control x,y positions of the bitmaps in the timer task and the paint will just paint where they go
g.drawBitmap(0,0, 360,
480, toBmp, 0, 0);
g.drawBitmap(0, 0, 360,
480, fromBmp, 0, 0);
// invalidate();
}
protected boolean touchEvent(TouchEvent event) {
if (!this.isFocus())
return true;
if (event.getEvent() == TouchEvent.CLICK) {
// invalidate();
}
return super.touchEvent(event);
}
}
Assuming you're working with version 5.0 or later of the OS, this page has a simple example:
http://docs.blackberry.com/en/developers/deliverables/11958/Screen_transitions_detailed_overview_806391_11.jsp
From where did you get the code sample posted in your question? That code does not appear to be close to working.
Update: you can actually animate transitions like this yourself fairly simply. Assuming you know how to use the Timer class, you basically have a class-level variable that stores the current x-position of your first Bitmap (the variable would have a value of 0 initially). In each timer tick, you subtract some amount from the x-position (however many pixels you want it to move each tick) and then call invalidate();.
In each call to the paint method, then, you just draw the first bitmap using the x-position variable for the call's x parameter, and draw the second bitmap using the x-position variable plus the width of the first bitmap. The resulting effect is to see the first bitmap slide off to the left while the second slides in from the right.
A caveat : Because this is java (which means the timer events are not real-time - they're not guaranteed to occur when you want them to), this animation will be kind of erratic and unsmooth. The best way to get smooth animation like this is to pre-render your animation cells (where each is a progressive combination of the two bitmaps you're transitioning between), so that in the paint method you're just drawing a single pre-rendered bitmap.

how to dynamically change image source in a silverlight for windows phone 7 project?

I'm working on a windows phone 7 project, with silverlight, and i'm trying to show 4 images in sequence to give the user the feeling of a short movie.
I have 4 urls pointing to 4 different jpeg images, and I'm using an Image control to show these jpeg in sequence.
The way I'm trying to achieve this is by doing:
private void RetrieveImages()
{
image1.ImageOpened += new EventHandler<RoutedEventArgs>(image1_ImageOpened);
frameNumber = 0;
gotoNextImage();
}
void image1_ImageOpened(object sender, RoutedEventArgs e)
{
System.Threading.Thread.Sleep(400);
gotoNextImage();
}
private void gotoNextImage()
{
if (frameNumber < 4)
{
webBrowser1.Dispatcher.BeginInvoke(()=> {
image1.Source = new System.Windows.Media.Imaging.BitmapImage(new Uri(cam.framesUrl[frameNumber]));
frameNumber++;
});
}
else
{
image1.ImageOpened -= image1_ImageOpened;
}
}
But this just don't work as expected. I'm sure I'm missing something about how to interact with the UI.
Can anyone point me in the right direction?
Which is the best way to achieve this?
Edited:
I'll explain better what's wrong with my code... probably it's unclear what happens.
I don't get any error with my code, but I don't see the "movie effect" too. It just show 1 single image, without iterating between the image collection.
I think it's a threading problem... kind of I'm not doing the right thing in the right thread to see the UI updating as expected...
This seams to work best.
xaml
<UserControl
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
mc:Ignorable="d"
x:Class="YourNamspace.YourClass"
d:DesignWidth="24"
d:DesignHeight="24">
<Grid x:Name="LayoutRoot">
<Image Name="YourImageName" Stretch="Fill" Source="YourPath" ImageOpened="onImageOpened"/>
</Grid>
</UserControl>
C#
using System;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Documents;
using System.Windows.Ink;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Media.Animation;
using System.Windows.Shapes;
using System.Threading;
namespace YourNameSpace
{
public partial class YourClass : UserControl
{
public int FirstImageIndex = 1;
public int LastImageIndex = 1000;
public int CurrentImageIndex = 1;
public YourClass()
{
InitializeComponent();
}
private void onImageOpened(object sender, System.Windows.RoutedEventArgs e)
{
Thread.Sleep(1000);
CurrentImageIndex = ( CurrentImageIndex == LastImageIndex ) ? FirstImageIndex : CurrentImageIndex++;
YourImageName.Source = new BitmapImage(new Uri("Your/path/to/image"+CurrentImageIndex+".jpg"), UriKind.RelativeOrAbsolute);
}
}
}
Hope that helps. I am pretty new to Silverlight.
So far the best way is to define the image as a resource. Via converter setting the image source.
But, your code should work fine as well. Try setting UriKind.RelativeOrAbsolute may be that should help. Because, this is the most common area while setting image source causes issue
HTH
Ok, I figured it out, and I think I also find a nice solution :) IMHO
I basically bound the Image.source to a proprerty of my class (that now extends INotifyPropertyChanged). But this gave me some issue about the transiction between images: since they were downloaded from internet there was a black images occurring between one images an the next one... but only the first time (i'm looping on a set of 4 images, looks like the video repeat), 'cause after that the images are cached.
So, what I've done is to cache the images the first time, without displaying the right Image control, but displaying instead another Image control (or whatever else) which says to the user "I'm loading".
For handle this scenario I've created a custom event:
public delegate void FramesPrefetchedEventHanlder();
public event FramesPrefetchedEventHanlder FramesPrefetched;
Now let's take a look at the RetrieveImages method:
private void RetrieveImages()
{
frameNumber = 0;
currentCycle = 0;
// set e very short interval, used for prefetching frames images
timer.Interval = new TimeSpan(0, 0, 0, 0, 10);
timer.Tick += (sender, e) => gotoNextImage();
// defines what is going to happen when the prefetching is done
this.FramesPrefetched += () =>
{
// hide the "wait" image and show the "movie" one
imageLoading.Opacity = 0;
image1.Opacity = 1;
// set the timer with a proper interval to render like a short movie
timer.Interval = new TimeSpan(0, 0, 0, 0, 400);
};
// when a frame is loaded in the main Image control, the timer restart
image1.ImageOpened += (s, e) =>
{
if (currentCycle <= cycles) timer.Start();
};
// start the loading (and showing) frames images process
gotoNextImage();
}
Ok, now what we need to handle is the step by step loading of the image and communicate when we finished the prefetching phase:
private void gotoNextImage()
{
timer.Stop();
if (frameNumber < 4)
{
CurrentFrame = new System.Windows.Media.Imaging.BitmapImage(new Uri(cam.framesUrl[frameNumber]));
frameNumber++;
}
else
{
// repeat the frame's sequence for maxCycles times
if (currentCycle < maxCycles)
{
frameNumber = 0;
currentCycle++;
// after the first cycle through the frames, raise the FramesPrefetched event
if (currentCycle == 1)
{
FramesPrefetchedEventHanlder handler = FramesPrefetched;
if (handler != null) handler();
}
// step over to next frame
gotoNextImage();
}
}
}
This works pretty fine to me... but since I'm new to Silverlight and Windows Phone 7 developement, any suggestion for improvement is welcome.

Resources