Best way to duplicate objects?

Hello everyone! Please educate me the most efficient way to duplicate objects. I used to perform Alt-D to make object instance, then i found out a similar way by using group instance(Shift-A -> Add Group Instance). What are their differences and which one is more efficient?

For example, i’ve a glass of whisky and i want to duplicate it over a mountain so that i can have a mountain of whisky:D, which way is cheaper? Alt-D or Group Instance? Thanks!

Cheaper relative to what aspect (adding, manipulating, rendering speed …)?

<alt-D> creates a new independent object sharing the same mesh, with separate logic and separate logic status.

Instances create a new independent empty + the instantiated objects sharing meshes and logic but separate logic status

Hello Monster Sifu!:smiley:

I meant cheaper in term of resources.

I just did some experiment, indeed, for Alt-D the logic was separated. Never knew that! (Edited)

So, does it mean we should use group instance if logic is not a concern? How about if we want to duplicate 10,000 object without attached logic, will Alt-D be equivalent performance wise? Otherwise, we need to Shift-A and hover down the menu 10,000 times. (i’m lazy, i know:D)

How about Group Instance vs. Linking? Which one is cheaper in term of resources?

Pardon me for the wave of questions, thanks!

I once read somewhere on this forum that using ALT+D actually uses more resources than SHIFT+D in terms of performance. I don’t really understand it myself, so I’ll be interested to hear why. I would assume that only having to use one mesh and texture/material for multiple objects would improve performance.

For randomly placed objects, linked it and spawn with python.

For non-randomly placed objects, linked it and continue the finger exercise.

Let me know if i’m wrong.