i have a problem of how to swap images isnide my 3 * 3 array, for example:
mImage image1 image2
image3 image4 image5
image6 image7 image8
mImage is the one i would like to swap with the rest, I can swap it only with the next one or with the one below(Sort of like a puzzler).
So the mImage can be swap only with image1 and image3.
What i thought is to swap with i+1 or with i+3 when the mouse is clicked.
Is that a good technique or is there a better approach to this problem?
Thank you
When an image is clicked, check if it's next to mImage (i.e. either it's X coordinate is the same as mImage.X and the difference in Y coordinates is equal to 1, or the other way round). If it's true, then you can swap.
Related
Please this fiddle I have copied my complete project in it
here if you open the fiddle in the output you can see an image, scribble on the image selecting pen,add text etc(like this perform some functions).then rotate the group using rotate button and then try to scribble you will understand what is the problem exactly.
In me view Problem is I am having a stage and a layer is added to the stage and a group is added to the layer and different elements like lines text etc are added to the group. then group is rotated the i am trying to draw the line based on the mouse position of the stage.But it is not coming correctly because the group got rotated the x and y what we are taking to draw a line is from stage.I need to take the x and y from the group not from the stage is their any way.If hav't understand please ask me or post a reply.
This should get you fairly close: http://jsfiddle.net/k4qB8/24/
// This rotates that added active line along with your group.
// This makes the draw direction correct
activeline.setRotationDeg(0-rootGroup.getRotationDeg());
// Here you'll have to figure a way to calculate how much to move the
// line over so the draw is on the correct spot
// This is as close as I got it
if(Math.abs(rootGroup.getRotationDeg()%360)==0)
activeline.move(rootGroup.getX()-375, rootGroup.getY()-175);
if(Math.abs(rootGroup.getRotationDeg()%360)==90)
activeline.move(rootGroup.getX()-175, rootGroup.getY()+375);
if(Math.abs(rootGroup.getRotationDeg()%360)==180)
activeline.move(rootGroup.getX()+375, rootGroup.getY()+175);
if(Math.abs(rootGroup.getRotationDeg()%360)==270)
activeline.move(rootGroup.getX()+175, rootGroup.getY()-375);
Also, add some more logic for counter-clockwise rotation, as this doesn't work 100%.
I think the real solution would be to just draw on separate layers for each rotation, kind of like this:
if (rotation is 90) : draw on lineLayer1;
if (rotation is 180) : draw on lineLayer2;
if (rotation is 270) : draw on lineLayer3;
if (rotation is 360 || 0) : draw on lineLayer4;
This way you could just rotate the layers which are not drawn on to simulate the feel of rotation.
My question is how to go to go to previous/next frame after 'monkey' and 'dog' are both dragged out of the scrollpane.
The file is placed below:
https://www.sugarsync.com/pf/D9726155_61875891_24948
Thanks for any advise.
2 ways I can think of
1- check x and y position of monkey if they are lower or higher than the x and y of scrollpane then go to next frame
2- set and invisible collision area and check if they collide.
I would help more with the code but i didn't find the objects to drag ^_^
I'm currently struggling on a problem that seems far beyond my maths capacities (been a long time since I've made some proper maths...) and I would appreciate some help on that.
Here's my setting :
I got some simple shapes (rectangles), and I "project" their bottom points on a line, coming from an Origin point.
Up to this point everything is fine.
But now I'd like to draw the original shape distorted as if it was projected with some perspective on a plane.
Please consider that I have nothing related to any rotation, isometric or any 3D or fake 2D perspective in my code, I'm only trying to draw some shapes using the graphics library to only have a feeling of something real.
Here's a quick drawing of what I'm trying to do :
What I know :
Origin point coordinates
the rect position & sizes
the red line position
the A & B points coordinates
What I want to determine is the coordinates of the C & D points, thing that could be easy if I wasn't struggling to find the "Origin bis" coordinates.
What I'm trying to do is to fake the projection of my rectangle on something that can be considered as a "floor" (related to the plane where my original rectangle is that can be seen as a wall).
Maybe I'm over-complicating the problem or maybe I fail to see any other easier way to do it, but I'm really not good anymore in any geometry or maths thing... :-(
Thanks a lot for your answers !
hmm i don't know if I undestood it correctly but I think you have too few input parameters:
you said the following information is given:
Origin point coordinates
the rect position & sizes
the red line position
the A & B points coordinates
I don't think it is possible to get your projected rectangle with this information alone.
Additionally, I think your green lines and the 'origin Bis' aren't helpful as well.
Perhaps, try this:
Supose, a blue line going through the points C & D is given as well.
Then you could find your projected rectangle by projecting the top of the rectangle onto that blue line.
So in summary:
You define an origin + two parallel lines, a red and a blue one.
Then you can project the top of the rect onto the blue line and the bottom of the rect onto the red line, yielding the points A,B,C,D
I hope this helps.
If I'm right, this code will show what you wanted to see.
First of all, I've ignored your initial setup of objects and information, and focused on the example situation itself; fake-projecting shadow for a "monolith" (any object is possible with the example below, even textured)
My reason was that it's really quite easy with the Matrix class of ActionScript, a handy tool worth learning.
Solution:
You can use the built-in Matrix class to do skew transform on DisplayObjects.
Try this example:
(The "useful" part lies in the _EF EnterFrame handler ;) )
import flash.display.MovieClip;
import flash.geom.Matrix;
import flash.events.Event;
import flash.display.BitmapData;
const PIP180:Number = Math.PI / 180;
const MAX_SHADOW_HEIGHT_MULTIPLIER:Number = 0.25; // you can also calculate this from an angle, like ... = Math.sin(angle * PIP180);
const ANIM_DEG_PER_FRAME:Number = 1.0 * PIP180; // the shadow creeps at a +1 degree per frame rate
var tx:BitmapData = new MonolithTexture(); // define this BitmapData in the library
var skew:Number = -10 * PIP180; // initial
var mono:MovieClip = new MovieClip();
mono.graphics.beginBitmapFill(tx);
// drawn that way the registration point is 0,0, so it's standing on the ground
mono.graphics.drawRect(0, -tx.height, tx.width, tx.height);
mono.graphics.endFill();
// align monolith to the "ground"
mono.x = stage.stageWidth / 2;
mono.y = stage.stageHeight - 100;
// make it be 100x300 pixel
mono.width = 100;
mono.height = 300;
var shad:MovieClip = new MovieClip();
// colored:
shad.graphics.beginFill(0x000000);
// or textured:
//shad.graphics.beginBitmapFill(tx);
shad.graphics.drawRect(0, -tx.height, tx.width, tx.height);
shad.graphics.endFill();
addChild(shad); // shadow first
addChild(mono); // then the caster object
addEventListener(Event.ENTER_FRAME, _EF);
function _EF(e:Event):void {
// animate skew on the positive half circle
skew = (skew + ANIM_DEG_PER_FRAME) % Math.PI;
// Matrix takes 6 parameters: a, b, c, d, x, y
// for this shadow trick, use them as follows:
// a = width scaling (as mono and shad are drawn in the same way, copy mono.scaleX for a perfect fit
// b = 0, because we don't want to project the vertical axis of transformation to the horizontal
// c = horizontal skew
// d = height scaling * skew * making it a bit flat using the constant
// x = mono.x, ...
// y = mono.y since originally mono and shad look alike, only the Matrix makes shad render differently
var mtx:Matrix = new Matrix(mono.scaleX, 0, Math.cos(skew), mono.scaleY * Math.sin(skew) * MAX_SHADOW_HEIGHT_MULTIPLIER, mono.x, mono.y);
shad.transform.matrix = mtx;
}
Now all you got to know to utilize this in your case, is the following N factors:
Q1: from what angle you want to project the shadow?
A1: horizontal factor is the skew variable itself, while vertical angle is stored as constant here, called MAX_SHADOW_HEIGHT_MULTIPLIER
Q2: do you want to project shadow only "upwards", or freely?
A2: if "upwards" is fine, keep skew in the positive range, otherwise let it take negative values as well for a "downward" shadow
P.S.: if you render the internals of the objects that they don't snap to 0 y as a base point, you can make them seem float/sink, or offset both objects vertically with a predefined value, with the opposite sign.
You face 1 very simple problem, as you said:
'What I want to determine is the coordinates of the C & D points, thing that could be easy if I wasn't struggling to find the "Origin bis" coordinates.'
But these co-ordinates relate to each other, so without one (or another value such as an angle) you cannot have the other. If you are to try this in 3D you are simply allowing the 3D engine to define 'Origin bis' and do your calculating for C and D itself.
So regardless you will need an 'Original bis', another value relating to the redline or your Rect for which to calculate the placement of C and D.
I remember making stuff like this and sometimes it's better to just stick with simple, you either make an 'Original bis' defines by yourself (it can be either stationary or move with the player/background) and get C and D the way you got A and B only that you use a lower line than the red line, or as I would of done, once you have A and B, simple skew/rotate your projection from those points down a bit further, and you get something the same as an 'Original bis' that follows the player. This works fine at simulating 'feeling of something real' but sadly as has been said, it looking real depends on what you are portraying. We do not know what the areas above or below the red line are (sky/ground, ground/water) and whether 'Origin' and 'Origin bis' is your light source, vanishing point, etc.
In Flash, pixels are calculated using twips, or twentieth of a pixel. Consequently, every position is always in multiples of 0.05. I haven't seen this mentioned in the HTML Canvas spec and am unable to trace the cursor position on Canvas. Does anyone know the accuracy of its pixel calculations?
Edit for clarification:
I'm referring more to Zeno's paradox which says in order to move something from point A to point B, it must first move to a point halfway between the two. And then halfway again, ad infinitum.
So if I want to move on the x axis from point 0 to 100 at 0.5:
At frame 1: 50
Frame 2: 75
Frame 3: 87.5
Then: 93.75, 96.875, 98.4375... etc.
So at what step does the Canvas actually round-up to the next pixel?
I'm unsure what you mean by accuracy of slicing.
Pixels on the Canvas can be drawn to a little less than 0.10, after which they make barely any visible impact.
Of course, if you scale, you can draw things that are 0.00125 pixels, and so on. But they won't be visible if you unscale.
http://jsfiddle.net/GvVD9/
(That first square block on the top-left is a pixel)
Accuracy of the mouse is an entirely different thing, in no way related to the canvas spec.
EDIT:
Well, we can sorta demonstrate that. We can draw a bunch of pixels with y values approaching 100 and see how they compare to a red pixel drawn with the y value 100.
http://jsfiddle.net/GvVD9/46/
Every single horizontally separated piece is just a single 1 by 1 pixel rect using the drawRect command.
50
75
87.5
93.75 // first black pixel you see in image
96.875
98.4375
99.21875
99.609375
99.8046875
99.90234375
99.951171875
99.9755859375
99.98779296875
99.993896484375
99.9969482421875 // last black pixel you see in image
I have a task:
I need to place about 100 sprites on one canvas (with prepared grid on it). I need to place them as invisible (circles) stones, on the board, and make visible only on mouseover.
The problem I come across is following, I can't place those objects accurately into the nodes on the grid.
E.g.
if I define stones (it's just a sprite, as I said earlier) this way:
var stone:StoneSprite = new StoneSprite();
stone.x = this.x + 2*cellWidth;
stone.graphics.beginFill( 0x000000 );
stone.graphics.drawCircle(stone.x , this.y + cellWidth, cellWidth/3 );
stone.graphics.endFill();
rawChildren.addChild(stone);
They don't sit on the node...
See image:
http://img.skitch.com/20091014-kuhfyjeg1g5qmrbyxbcerp4aya.png
And if I do it this way:
var stone:StoneSprite = new StoneSprite();
stone.graphics.beginFill( 0x000000 );
stone.graphics.drawCircle(this.x + 2*cellWidth , this.y + cellWidth, cellWidth/3 );
stone.graphics.endFill();
rawChildren.addChild(stone);
The stone is displayed correctly in the grid node... See image 2:
http://img.skitch.com/20091014-f595tksjxramt98s7yfye591bh.png
So I wonder what is the difference between these 2 approaches.
Also, I think I need to pass correct coordinates to the stone class... In case I would like to change some properties of the stone object. E.g. visibility, or radius.
Could you please suggest, what's wrong in defining coordinates as stone.x, stone.y
How to fix the problem with incorrect positioning.
Would really appreciate ideas about the problem, I am trying to solve for so long :(
Assume x & y are 30 and cellWidth is 30.
First Example:
stone.x = 30 + 60; //90
drawCircle(90, 60, 10);
This means if you were to draw a rectangle around your circle, it would be at [170,50]. (x,y).
Second Example:
stone.x = 0;
drawCircle(90, 60, 10)
This means the rectangle around your circle is at [80,50];
In the first example, you are moving the sprite to position x==90. Then drawing a circle whose center is at x==90 inside the sprite. So relative to this, you're at x==180. But because a circle's x,y coords are the center, subtract 10 for the radius to get the boundary x position.
In the second example, the sprite defaults to position x==0 relative to this and you're drawing the circle inside the sprite at position x==90. (therefore it begins at x==80).
I am not sure what's causing the issue - might be some padding induced by the container - can't say without testing. But I believe that adding a Sprite (say board) to canvas.rawChildren and using it as the parent for the grid and stones would fix the issue.