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/**
Displays an animated Game Object
@author <a href="mailto:matthewcasperson@gmail.com">Matthew Casperson</a>
@class
*/
function AnimatedGameObject()
{
/**
Defines the current frame that is to be rendered
@type Number
*/
this.currentFrame = 0;
/**
Defines the frames per second of the animation
@type Number
*/
this.timeBetweenFrames = 0;
/**
The number of individual frames held in the image
@type Number
*/
/**
Time until the next frame
@type number
*/
this.timeSinceLastFrame = 0;
/**
The width of each individual frame
@type Number
*/
this.frameWidth = 0;
/**
Initialises this object
@param image The image to be displayed
@param x The position on the X axis
@param y The position on the Y axis
@param z The depth
@param frameCount The number of animation frames in the image
@param fps The frames per second to animate this object at
*/
this.startupAnimatedGameObject = function(/**Image*/ image, /**Number*/ x, /**Number*/ y, /**Number*/ z,
/**Number*/ frameCount, /**Number*/ fps)
{
if (frameCount <= 0) throw "framecount can not be <= 0";
if (fps <= 0) throw "fps can not be <= 0"
this.startupVisualGameObject(image, x, y, z);
this.currentFrame = 0;
this.frameCount = frameCount;
this.timeBetweenFrames = 1/fps;
this.timeSinceLastFrame = this.timeBetweenFrames;
this.frameWidth = this.image.width / this.frameCount;
}
/**
Draws this element to the back buffer
@param dt Time in seconds since the last frame
@param context The context to draw to
@param xScroll The global scrolling value of the x axis
@param yScroll The global scrolling value of the y axis
*/
this.draw = function(/**Number*/ dt, /**CanvasRenderingContext2D*/ context, /**Number*/ xScroll, /**Number*/
yScroll)
{
var sourceX = this.frameWidth * this.currentFrame;
context.drawImage(this.image, sourceX, 0, this.frameWidth, this.image.height, this.x - xScroll, this.y -
yScroll, this.frameWidth, this.image.height);
this.timeSinceLastFrame -= dt;
if (this.timeSinceLastFrame <= 0)
{
this.timeSinceLastFrame = this.timeBetweenFrames;
++this.currentFrame;
this.currentFrame %= this.frameCount;
}
}
}
AnimatedGameObject.prototype = new VisualGameObject;
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