Clarify Loop end condition in BufferGeometry.merge()

[takahirox]

Comment inline.

[takahirox]

(Update: Clean up the comment)

This method seems to expect attributeArray1 size won't be resized.

j can be bigger than the attributeArray1.length here but attributeArray1/2 are typed array then attributeArray1[ index ] = value; // index >= attributeArray1.length has no effect.

I think better to make clear the behavior by clarifying loop end condition. And it'll be efficient in case j can be bigger than attributeArray1.length because it can cut off no effect operation .

[donmccurdy]

Because assigning to an out-of-bounds index in a typed array has no effect and throws no error, this change has no effect on the method output, and just makes the actual behavior more explicit right? Sounds good to me.

[takahirox]

Yes, that's right. Thanks for clarifying.

[mrdoob]

Would this be more clear?

var attributeOffset = attribute2.itemSize * offset;
var length = Math.min( attributeArray2.length, attributeArray1.length - attributeOffset );

for ( var i = 0, j = attributeOffset; i < length; i ++, j ++ ) {

	attributeArray1[ j ] = attributeArray2[ i ];

}

[mrdoob]

/ping @takahirox

[takahirox]

Sorry for the late. Updated.

[mrdoob]

Thanks!