as3 draw smoother round corners - actionscript-3

I use the following script to draw:
private function drawBkg():void {
_bkg_shp.graphics.clear();
_bkg_shp.graphics.lineStyle(1, 0x0, 1, false, LineScaleMode.NORMAL, CapsStyle.ROUND, JointStyle.ROUND);
_bkg_shp.graphics.moveTo(_round, 0);
_bkg_shp.graphics.lineTo(_width - _round, 0);
_bkg_shp.graphics.curveTo(_width, 0, _width, _round);
_bkg_shp.graphics.lineTo(_width, _height - _round);
_bkg_shp.graphics.curveTo(_width, _height, _width - _round, _height);
// draw down arrow
const startPont:int = (_width + _arrowBase) * 0.5;
_bkg_shp.graphics.lineTo(startPont, _height);
_bkg_shp.graphics.lineTo(int(_width * 0.5), _height + _arrowHeight);
_bkg_shp.graphics.lineTo(int(startPont - _arrowBase), _height);
_bkg_shp.graphics.lineTo(_round, _height);
_bkg_shp.graphics.curveTo(0, _height, 0, _height -_round);
_bkg_shp.graphics.lineTo(0, _round);
_bkg_shp.graphics.curveTo(0, 0, _round, 0);
}
And the result is:
Do anyone know how to remove the fuzziness of the of the rounds? Snapping to the pixel, depends on the sizes can improve or worsen the shape.

Increasing the thickness of the line stroke weight will help:
import flash.display.CapsStyle;
import flash.display.JointStyle;
import flash.display.LineScaleMode;
graphics.lineStyle(2,
0x0,
1.0,
true,
LineScaleMode.NORMAL,
CapsStyle.SQUARE,
JointStyle.MITER);

The common solution to avoid that problem with lines is just not to use them :)
You can draw round rectangles only by fills:
For example that code draws one:
/**
* Draw rectangle with rounded corners with fills (without lines) for
* nice scaling of corners
*/
public static function drawRoundRectAsFill (graphics:Graphics,
x:Number, y:Number,
w:Number, h:Number,
radius:Number,
lineColor:uint=0x000000, fillColor:uint=0xffffff,
lineThickness:Number=1,
lineAlpha:Number=1, fillAlpha:Number=1):void
{
graphics.lineStyle(0,0,0);
graphics.beginFill(lineColor, lineAlpha);
graphics.drawRoundRect(x, y, w, h, 2*radius, 2*radius);
graphics.drawRoundRect(x+lineThickness, y+lineThickness, w-2*lineThickness, h-2*lineThickness, 2*radius-2*lineThickness, 2*radius-2*lineThickness);
graphics.endFill();
graphics.beginFill(fillColor,fillAlpha);
graphics.drawRoundRect(x+lineThickness, y+lineThickness, w-2*lineThickness, h-2*lineThickness, 2*radius-2*lineThickness, 2*radius-2*lineThickness);
graphics.endFill();
}

Use shapes for everything. Don't use lines. Ever.

Related

Libgdx blending contrast issue in render();

In a Libgdx 1.x Stage, my goal is to apply a dark semi transparent mask on my screen except an area that should display the original screen.
My global render method:
public void render() {
Gdx.gl.glClearColor(0, 0, 0, 1);
Gdx.gl.glClear(GL20.GL_COLOR_BUFFER_BIT);
batch.setShader(null);
update();
stage.act(Gdx.graphics.getDeltaTime());
stage.draw();
batch.begin();
darkener.draw(batch, 0.7f);
spotlight.draw(batch, 1f);
batch.end();
}
Both instances of objects Darkener and Spotlight are Sprites made from a pure white 4x4 texture:
spotlight = new Sprite(new Texture(Gdx.files.internal("data/ui/whitepixel.png")));
darkener = new Sprite(new Texture(Gdx.files.internal("data/ui/whitepixel.png")));
I give my Darkener object the size of the screen, and my Spotlight object the size of the area I want not to be darkened.
Here is the draw method of my object darkener:
public void draw(Batch batch, float alpha) {
darkener.draw(batch, alpha);
}
And the draw method of my Spotlight object:
public void draw(Batch batch, float alpha) {
batch.setBlendFunction(GL20.GL_DST_COLOR, GL20.GL_SRC_ALPHA);
spotlight.draw(batch, alpha);
batch.setBlendFunction(GL20.GL_SRC_ALPHA, GL20.GL_ONE_MINUS_SRC_ALPHA);
}
My problem is about blending:
With the parameters:
darkener.draw(batch, 0.7f);
spotlight.draw(batch, 1f);
The preserved (spotlight) area is darker than the original.
With the parameters:
darkener.draw(batch, 0.3f);
spotlight.draw(batch, 1f);
The preserved (spotlight) area is brighter (saturated) than the original.
With the paremeters:
darkener.draw(batch, 0.5f);
spotlight.draw(batch, 1f);
The preserved (spotlight) area is exactly like the original (so, as I want it). The problem is that I want to be able to set different values for my Darkener either < 0.5f or > 0.5f.
What I am doing wrong?
The blend function you're using for the spotlight takes the current pixel brightness and multiplies it by (1+alpha).
So if you darken to 0.7 of brightness (using a darkener alpha of 0.3), you want the spotlight to multiply the brightness by 1/0.7 = 1.429 so you should use a spotlight alpha of 0.429. So:
spotlightAlpha = 1/(1-darkenerAlpha) - 1; //assuming darkener RGB is black
The problem is if you darken to less than 0.5 brightness (darkner alpha > 0.5), because alpha cannot be greater than 1. You would have to run the spotlight with alpha 1 repeatedly until the brightness is above 0.5 and then one more time with the appropriate value.
You will lose color precision the darker you go so this method may not be suitable. Might want to consider drawing 8 dark boxes instead. And if you want the spotlight to be non-rectangular you can make its sprite inverted to fill in the middle rectangle.

html5 canvas - emulate 3d rotation of image

I have an image which has square shape. I want to rotate and squeeze it to get 3d effect like on the pictures below:
Source image:
Rotate to 0 degrees and squeeze:
Rotate to 45 degrees and squeeze:
Something like this.
I have played around Math and tried to change Width and Height of the image by multiplying to Sin and Cos of angle.
var w = image.width*Math.cos(angle* TO_RADIANS);
var h = image.height*Math.sin(angle* TO_RADIANS);
h=h*2/3; //squeezing the height
ctx.drawImage(image, 0, 0, w, h);
But I am not good at mathematics, so I hope somebody may help me to solve this issue.
I've resolved my problem. I squeezed my image in photoshop. So, the image became 300x150 size and looked like the second picture above. Then I applied a function below anytime, when I needed to redraw the image according to the angle:
var TO_RADIANS = Math.PI/180;
ctx.save();
ctx.translate(x, y);
ctx.rotate(angle * TO_RADIANS);
var w = image.width-Math.abs((image.width/2)*Math.sin(angle* TO_RADIANS));
var h = image.height+Math.abs((image.height)*Math.sin(angle * TO_RADIANS));
ctx.translate(-w/2, -h/2);
ctx.drawImage(image, 0, 0, w, h);
ctx.restore();
Now it works pretty well.
You should look into a transform matrix.
Something like this:
ctx.transform(1, 0.6, -.8, .5, 20, 0);
http://jsfiddle.net/ericjbasti/nNZLC/
some links for you :
http://www.w3schools.com/tags/canvas_transform.asp
https://developer.apple.com/library/safari/documentation/AudioVideo/Conceptual/HTML-canvas-guide/MatrixTransforms/MatrixTransforms.html

Tweening Sprite size using GreenSock in AS3

I've seen examples where it's possible to tween a rectangle using scaleX, but I can't find anything that tweens a circle. (The "circle" that I'm drawing is actually a donut shape and I want the outside circle to be the one that is tweened).
var resizeVar:Number = 75;
myCircle.graphics.drawCircle((myCircle.width/2), (myCircle.height/2), resizeVar);
myCircle.graphics.drawCircle((myCircle.width/2), (myCircle.height/2), 75);
I tried doing it this way, but this throws lots of errors. I don't think it's possible this way:
TweenMax.to(myCircle, 2, {resizeVar:150, ease:SlowMo.ease.config(1, 0)});
Normally with display objects, it is done this way. It doesn't work with this "donut" though:
TweenMax.to(myRectangle, 2, {scaleX:1.5, scaleY:1.5 ease:SlowMo.ease.config(1, 0)});
So my question is, how can I tween the radius size of my outside circle?
EDIT: This is how the donut is being drawn, so the resizeVar needs to change from 75 to 150.
var myCircle:Sprite = new Sprite();
myCircle.graphics.beginFill(0xbbbbbb);
myCircle.graphics.drawCircle(0, 0, 150); // this is what should be tweening/scaling
myCircle.graphics.drawCircle(0, 0, 75); // this should stay the same
myCircle.graphics.endFill();
addChild(myCircle);
You should be able to tween the scaleX and scaleY properties of ANY displayObject:
var radius:Number = 75;
var myCircle:Sprite = new Sprite();
myCircle.graphics.beginFill(0);
myCircle.graphics.drawCircle(radius/2, radius/2, radius);
myCircle.graphics.endFill();
addChild(myCircle);
TweenMax.to(myCircle, 2, {scaleX:2, scaleY:2, ease:SlowMo.ease.config(1,0)});
EDIT
This is how you would scale just the outside of the donut:
var resizeObject:Object = { innerRadius:75, outerRadius:150 };
myCircle = new Sprite();
myCircle.graphics.beginFill(0xbbbbbb);
myCircle.graphics.drawCircle(0, 0, resizeObject.outerRadius);
myCircle.graphics.drawCircle(0, 0, resizeObject.innerRadius);
myCircle.graphics.endFill();
addChild(myCircle);
TweenMax.to(resizeObject, 2, {outerRadius:300, ease:SlowMo.ease.config(1,0), onUpdate:updateCircle, onUpdateParams:[resizeObject]});
function updateCircle(resizeObject:Object):void
{
myCircle.graphics.clear();
myCircle.graphics.beginFill(0xbbbbbb);
myCircle.graphics.drawCircle(0, 0, resizeObject.outerRadius);
myCircle.graphics.drawCircle(0, 0, resizeObject.innerRadius);
myCircle.graphics.endFill();
}
The reason it works with the rectangle is that you are changing the scale of the rectangle. When you change the scale Flash Player adjusts the scale of the display object containing your graphics.
However, with the circle, you are trying to change the radius of the circle. The radius is only used when you draw the circle with the drawCircle() method. One way to tween the radius is to use your tween to re-draw the circle many times (not that ideal).
To re-draw the circle with a new radius, you can use the onUpdate callback that TweenMax offers:
TweenMax.to(myCircle, 2, {resizeVar:150, onUpdate: onUpdateCallback, onUpdateParams: [resizeVar] });
function onUpdateCallback(radius):void
{
myCircle.graphics.drawCircle(myCircle.graphics.drawCircle((myCircle.width/2), (myCircle.height/2), radius);
}
[Edit]
Note, I've added some params that you need to pass to the onUpdateCallback() function. I've also modified the function to add a radius parameter, and then use the radius when drawing the circle.
In regards to "trying to change the outside circle of this donut", this may be more complex. You might need to draw both circles of the donut. You might need to also call graphics.clear() before you draw the circle.
However, perhaps the answer from #Marcela is better, just change the scaleX and scaleY of the object you've already drawn. But if you need to get to a specified radius, the only way to do that is by re-drawing the circle(s) on each interval of the tween.

as3 wipe fade alpha using tween

Is it possible to fade the alpha with a soft wipe transition using as3 tween?
I thought maybe http://www.greensock.com might have the answer but I have found nothing. I would like the image to slowly fade away from one side to the other. A soft dissolve.
I thought maybe its possible using a mask but I don't think masks accept alphas otherwise it could be done that way.
Actually masks allow alphas. It's kind of a hack. You should try writing this in code:
maskMC.cacheAsBitmap = true;
objMC.cacheAsBitmap = true;
objMC.mask = maskMC;
Where objMC is your animated MovieClip and maskMC is your Mask that contains a gradient shape with transparency. See an example here: Link
You can also achieve this effect using Greensock. Code would look like this:
TweenLite.to(objMC, 1, {"alpha":0, "x":objMC.x + 10});
When using TweenLite, you need to provide object to animate, duration of animation and an instance of an Object class (that's stuff we write between curly braces). This instance contains all the values we want to change gradually.
You can accomplish this by using the ALPHA blendmode.
Make a shape that has a gradient whose alpha goes from full to nothing, then make it's blend mode ALPHA, put it in the same container as your item you wish to mask.
Then set the container blendmode to LAYER
Psuedo Code:
container.blendMode = BlendMode.LAYER; //container holds both the mask and the thing you want masked
maskObj.blendMode = BlendMode.ALPHA;
drawMaskGradients();
Here is a function I've used in the past to create said mask via code: (itemContainer is the object I'm masking)
You could however do this all in the Flash IDE using design tools.
softMaskSprite = new Sprite();
this.blendMode = BlendMode.LAYER;
softMaskSprite.blendMode = BlendMode.ALPHA;
softMaskSprite.mouseChildren = false;
softMaskSprite.mouseEnabled = false;
this.addChildAt(softMaskSprite,this.getChildIndex(itemContainer)+1);
//Create Sides
var top:Shape = new Shape();
var matr:Matrix = new Matrix();
matr.createGradientBox(areaWidth + (softMaskWidth * 2), softMaskWidth, 90 * (Math.PI / 180), 0, 0);
top.graphics.beginGradientFill(GradientType.LINEAR, [0xFF0000, 0x0000FF], [0,1], [0,255], matr, SpreadMethod.PAD);
top.graphics.drawRect(0, 0, areaWidth + (softMaskWidth * 2), softMaskWidth);
top.graphics.endFill();
top.x = softMaskWidth * -1;
top.y = softMaskWidth * -1;
softMaskSprite.addChild(top);
//BOTTOM
var bottom:Shape = new Shape();
matr = new Matrix();
matr.createGradientBox(areaWidth + (softMaskWidth * 2), softMaskWidth, 90 * (Math.PI / 180), 0, 0);
bottom.graphics.beginGradientFill(GradientType.LINEAR, [0xFF0000, 0x0000FF], [1,0], [0,255], matr, SpreadMethod.PAD);
bottom.graphics.drawRect(0, 0, areaWidth + (softMaskWidth * 2), softMaskWidth);
bottom.graphics.endFill();
bottom.y = areaHeight;
bottom.x = softMaskWidth * -1;
softMaskSprite.addChild(bottom);

ActionScript 3.0 - Line Gradient Positioning?

i'm drawing a line with a gradient style, but for some reason the line's x position appears to be about 4 or 5 instead of 0 when added to the display list. tracing the line's x postion returns 0, but it's clearly visible that the line is not positioned at that coordinate.
if i remove the gradient box then it is positioned correctly, but that's not a solution since i would lose the gradient.
i'm targeting FlashPlayer 11 / AIR 3 using Flash Builder. any ideas?
//Constants
private static const LINE_COLOR:uint = 0xFFFFFF;
private static const LINE_WIDTH:uint = 10;
//Variables
private var volumeLineShape:Shape = new Shape();
private var volumeLineMatrix:Matrix = new Matrix();
// ~
volumeLineMatrix.createGradientBox(widthProperty, heightProperty);
volumeLineShape.graphics.clear();
volumeLineShape.graphics.lineStyle(LINE_WIDTH, 0, 1.0, false, LineScaleMode.NONE, CapsStyle.NONE);
volumeLineShape.graphics.lineGradientStyle(GradientType.LINEAR, [LINE_COLOR, LINE_COLOR, LINE_COLOR], [0.0, 1.0, 0.0], [0, 255 * toneProperty, 255], volumeLineMatrix);
volumeLineShape.graphics.moveTo(0, heightProperty - heightProperty * volumeProperty);
volumeLineShape.graphics.lineTo(widthProperty, heightProperty - heightProperty * volumeProperty);
Just gived some static values to width and position, and it drawed a line that left corner and line is transparent at corner. Check your values and change your background to see white transparent part of line.
volumeLineShape.graphics.clear();
volumeLineShape.graphics.lineStyle(LINE_WIDTH, 0, 1.0, false, LineScaleMode.NONE, CapsStyle.NONE);
volumeLineShape.graphics.lineGradientStyle(GradientType.LINEAR, [LINE_COLOR, LINE_COLOR, LINE_COLOR], [0.0, 1.0, 0.0], [0, 255 * toneProperty, 255], volumeLineMatrix);
volumeLineShape.graphics.moveTo(0, 0);
volumeLineShape.graphics.lineTo(100, 100);
it's a banding problem. setting zero position at alpha 0 and another zero position at alpha 1 causes issues.