corehtml5canvas / code Goto Github PK

   function drawHand(loc, isHour) {
       // ...
   }

     // ...
   function drawHands() {
       // ...
       drawHand(hour*5 + (date.getMinutes()/60)*5, true, 0.5);
       drawHand(date.getMinutes(), false, 0.5);
       drawHand(date.getSeconds(), false, 0.2);
   }

I cannot find how the third parameter is used? Did it mean the length of the hand?

I believe it should have been
return { x: (x - bbox.left) * (canvas.width / bbox.width),
y: (y - bbox.top) * (canvas.height / bbox.height)
};
instead of(missing brackets)
return { x: x - bbox.left * (canvas.width / bbox.width),
y: y - bbox.top * (canvas.height / bbox.height)
};

in windowToCanvas method of example.js in example-1.5.

Upendra

Object approaching the hypotenuse bounce as if it were a square extending the x of the x-most endpoint and the y of the y-most/least(depending on orientation) endpoint of the hypotenuse to an imaginary fourth corner.

Closing the polygon by creating a fourth point equal to the first gives the correct response.

https://github.com/corehtml5canvas/code/blob/master/ch02/example-2.31/example.js#L199

fill()

In example-8.10, try to update the 1st polygon points to:
[ new Point(25.5, 100), new Point(200.5, 200),
new Point(400.5, 200), new Point(600.5, 160),
new Point(600.5, 300), new Point(16.5, 300) ]
If you dragged any other polygon between the 1st polygon faced edges without real intersection, it will detect collision while there is no collision