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INTRODUCTION TO HTML 5 CANVAS (PART II)

INTRODUCTION TO HTML 5 CANVAS (PART II) 




In the last post we saw how canvas tag is used and done some very basic things with it. This time we’ll be doing some more interesting stuff. Last time we drawn a rectangle and a line to our canvas.

Having Fun with Loops

We can draw multiple object on our canvas at a time. This can be done with help of loops or the setInterval () function. We can change the coordinates of object and redraw it with the new coordinates . Here are some examples,
We can also change x and y at the same time  to draw an inclined pattern,
Try these out, also try to make different patterns of your own wish.

Making Things Move

Okay so we can draw things on canvas, but that would be boring if they would just sit there and don’t do anything. To make things move on our canvas we can change the coordinates of them and redraw them with the new coordinates while clearing the canvas with each iteration . Let’s understand it with an example,


1           1) First draw a rectangle, but this time are going to pass the parameters to the fillRect() function
          using  variables as done above. 
       
          
        2) Now, make the coordinates change with every iteration like this,


  
              3)Now clear the canvas with each iteration like this Hurray!!  Its moving










Here the object move in a path .These paths then can be  controlled by condition checking the coordinates like this.                                                                                                                                                                                                                                                                                                                                                            
                                                     
Here it will stop as it reaches the boundary of canvas and won’t go outside the screen. The screen.width  return the width of our canvas as we have assigned it to the variable screen.




This is it for now guys.….   


                                           Thanks of giving your precious time……..                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     





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