Rails migration column types
:primary_key, :string, :text, :integer, :float, :decimal, :datetime, :timestamp, :boolean
:primary_key, :string, :text, :integer, :float, :decimal, :datetime, :timestamp, :boolean
壁紙 【かべがみ】 (n) (1) wallpaper; (2) (comp) wallpaper; background image; desktop image; (P); EP
Today I learned a fast way to divide by two or multiply by two - use the bitshift operators. (e.g. 10 » 1 = 5 and 10 « 1 = 20)
This isn't exactly news, but I created an account on the Japanese social network/code sharing site Wonderfl. It's kind of cool... you can use the site to automatically compile Actionscript 3 code, then save it for other people to check out. If you see some code you like, or that sparks a new idea, you can "fork" it — copy it and save your own version. I was kind of surprised... I added two small demos on Monday, and by Wednesday some other users had already modified my demos. There's a lot of random crap, but you can also learn some cool techniques by browsing through the user-submitted code. If you have any interest in Actionscript, you should check it out.
I think one of the main disadvantages of using the Flex compiler to create Flash programs is that animation is a bit more difficult to create (although, to tell the truth, I've never used the Flash IDE enough to be able to compare them). I think for most simple games, you can get away with not animating any of your characters. But once you get into creating games that have more detailed characters, you pretty much need to add some sort of animation. We can do that pretty easily by loading multiple images into a DisplayObjectContainer (such as a Sprite) and then showing/hiding each image in turn. Take a look at the following example:
package {
import flash.display.Sprite;
import flash.events.Event;
import flash.utils.getTimer; // for getTimer()
// Set SWF FPS, etc.
[SWF(frameRate='30', width='200', height='200', backgroundColor='0xffffff')]
public class AnimationExample extends Sprite {
// For frame rate info
public var ticks:Number = 0;
public var framesPerSecond:Number;
public var frameTimer:Number = 0;
public var currentAnimationFrame:int = 0;
// For animation
[Embed(source="run-1.svg")]
public var animationFrame1:Class;
[Embed(source="run-2.svg")]
public var animationFrame2:Class;
[Embed(source="run-3.svg")]
public var animationFrame3:Class;
public var character:Sprite;
public function AnimationExample():void {
// Create new sprite for animation frames
character = new Sprite();
// Add frames, hide all but the first one
character.addChild(new animationFrame1());
character.addChild(new animationFrame2());
character.addChild(new animationFrame3());
character.getChildAt(1).visible = false;
character.getChildAt(2).visible = false;
this.addChild(character);
// This will call the animation function
this.addEventListener(Event.ENTER_FRAME, enterFrame);
}
public function enterFrame(e:Event = null):void {
// getTimer() provides # of ms since Flash Player started
var currentTicks:Number = getTimer();
// Figure out how many seconds each frame is displaying for
var secondsPerFrame:Number = (currentTicks - ticks) / 1000;
// For the heck of it, you can also determine FPS
framesPerSecond = 1 / secondsPerFrame;
// Set this var for the next iteration
ticks = currentTicks;
// Increment the timer
frameTimer += secondsPerFrame;
// Compare the frameTimer value against the number of seconds you want each frame to display
if(frameTimer > 0.5) {
// Reset the frame timer
frameTimer = 0;
// Hide the first frame
this.character.getChildAt(0).visible = false;
// Move the last frame up to be first
this.character.setChildIndex(this.character.getChildAt(2), 0);
// Show the new first frame
this.character.getChildAt(0).visible = true;
}
}
}
}
Download the code, .swf, and (bad) graphics.
In addition to the setChildIndex() function that swaps the depth of each animation frame, there's also some code that obtains the current frame rate, which helps set the speed of the animation. In some games, the motion of all the characters can be limited by a number derived by the frame rate, which helps ensure that the game runs the same speed on different computers. This isn't totally necessary in Flash, however, since it's possible to limit frame rate by using [SWF(frameRate='XX')] at the beginning of your Actionscript package.