Why is this .blend file lagging?

(thebombmartin) #1


I have a student who has downloaded files form BlendSwap. She has included many of them in a single scene. This file won’t stop lagging, it’s almost impossible for her to work on. Why is this? Would love to learn why this is happening. Thanks!


(Pixelfox) #2

What version of Blender is she using?

(Lumpengnom) #3

What kind of GPU and which OS does she have?

(thebombmartin) #4

She is using version 2.79b.

(thebombmartin) #5

macOS Sierra Version 10.12.6
GPU is Intel Iris Pro 1536 MB

(Lumpengnom) #6

Well, her system is rather useless. If she has included a lot of stuff into this file it is expected to run slow on a machine like this.
My wife has a similar MacBook Pro and the GPU is simply not made for things like 3D programs.

(thebombmartin) #7

I hear you. This doesn’t look like a complicated file. I’ve been teaching blender on these machines for a decade but I’ve never seen a problem like this. Much more complicated files than this have worked fine. Did you get a chance to look at it? Does it have to do with the textures that came with the mesh objects she used from Blendswap?

(Lumpengnom) #8

It runs without problems on a GTX 1070. It has more than 5 million triangles which doesn´t seem like a completely trivial amount of geometry for an integrated GPU to me.

Does it run decently if you set the display method to solid instead of material?

(thebombmartin) #9

It does! Thanks so much! So how should she go about texturing without hitting the render image button all the time? The kids love that rendered view button.
What does this screenshot mean?

(Lumpengnom) #10

I think it means that auto running python is disabled in the preferences and that the file is trying to use Python somewhere. Perhaps some object has a driver with an expression or something like that?

(Lumpengnom) #11

There is an object (_windowFrame) somewhere out in left field which has several drivers. The driver "key_blocks[“Thickness”] has an invalid path.

(BigBlend) #12

The books have 1 million polygons. The screws have 1.4 million polygons!!! That is a crazy amount.

(Lumpengnom) #13

If your kids are old enough you could teach them how to use dupli gorups

(thebombmartin) #14

We have used dupli groups for particle systems. They are US high schoolers age 14-18. What should she use them for in this scene?

This place is great. I learn so much!

(Lumpengnom) #15

Make DupliGroups out of things like the screws, the fan lamps, the fan blades the books and all that stuff. Texture one of them in isolation mode. Making them Dupli Groups saves a lot of resources.

If you want to go deeper put one of these objects - for example a screw - into a separate file and instead of having the scew multiple times in your scene link it to your “master” file from the the “screw file” as a dupli group.
You can then texture it in the screw file without lag and see the result in you master file on all screws. Do the same with all objects you have several of in the scene.

If all of this is too complicated at least create linked data objects instead of making all objects unique when dealing with objects that are there multiple times.

Or make them particles. The fan blades for example could be particles. The screws, too. The books would be perfect. But the setup is a bit more complicated of course.