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daz1761
07-22-2011, 11:37 AM
Unbelievable :(

I've not long had my new LW10 book by Dan Ablan and I started off with a bit of hard dynamics.

The short detailed video entails you building a simple brick wall with a floor and a ball to smash through the wall

I have copied all his parameter settings and for some unknown reason, the brick wall is just crumbling down and completely ignoring the ball which has a sphere collision 700mm wrapped around it.

So I have 3 layers,

wall
ball
floor

the floor and ball have a collision assigned to it and the wall has a HardFX with the gravity set to -9.8, resistance 1.0 etc, exactly as the video tutorial shows

I have even loaded up his lesson file and it works and mine just doesnt :(

Like i say, the brick wall just completely ignores the ball hurling towards it.

Any help would be much appreciated please, i really want to knock down this wall :)

nickdigital
07-22-2011, 12:08 PM
Have you compared your settings against Dan's? Maybe there's a setting that's just slightly different that you're missing.

Can you post your file? That would make helping you a lot easier.

daz1761
07-22-2011, 12:13 PM
Quick Update

After changing the "ball" object dynamics "type" to "object" instead of "sphere" it seems to work

But i noticed the wall instantly starts "bouncing" before the "ball" hits it??

This also happens on his video, is there a way to make the wall solid before my collision object hits it?

Many thanks

daz1761
07-22-2011, 12:17 PM
Thanks

Yes i have compared setting until i my eyes nearly popped out of my head lol

Like i updated, it seems to work now i selected "type" object but not "Sphere"

I have attached my scene file, there are no surfaces just a few layers of basic primitives. Also this is the file that seems to work now after changing the above but i really want to know why the "Sphere" type wouldn't work?

Many thanks

nickdigital
07-22-2011, 12:29 PM
You need to post the objects too. You only posted the Layout file.

daz1761
07-22-2011, 12:46 PM
Sorry

Here they are

Thanks

nickdigital
07-22-2011, 01:23 PM
...i really want to know why the "Sphere" type wouldn't work?


My guess is that it's because you're using an actual object. If you add a null and set it to Sphere it works as if the null is a ball.

daz1761
07-22-2011, 02:04 PM
Many thanks much appreciated

So next time, if I make a primitive ball intended to smash a wall in, parent it to a null object then? then assign a dynamic collision to the null object?

Also do you know why the wall starts bouncing before the ball hits it?

Many thanks

nickdigital
07-22-2011, 02:08 PM
Many thanks much appreciated

So next time, if I make a primitive ball intended to smash a wall in, parent it to a null object then? then assign a dynamic collision to the null object?

Also do you know why the wall starts bouncing before the ball hits it?

Many thanks

You could...or just use the Object Collision mode on your object.

For your wall, under Collision tab set the Start by Collision pulldown to be Start By Collision. I believe you had it set to None.

daz1761
07-22-2011, 02:17 PM
You could...or just use the Object Collision mode on your object.

For your wall, under Collision tab set the Start by Collision pulldown to be Start By Collision. I believe you had it set to None.

Excellent, thank you very much, you have been a huge help, well yes, that was the only way i got it working in the end

Just another question if i may, I have ticked the "Start By Collision" and it works but some of the bricks don't fall as they would naturally and stay in mid air

Many thanks

nickdigital
07-22-2011, 02:51 PM
Are you talking about bricks that are still attached to the wall or bricks that have been blown away?

daz1761
07-22-2011, 03:02 PM
Sorry,

the bricks that are left standing, please find attached a screen grab of the bricks

Many thanks

skywalker113
07-22-2011, 03:18 PM
I think your going to have to make more collision objects in order to get a propor result. Use them to fix the weird areas. Lightwave does not have a strong physics system.

Snosrap
07-22-2011, 08:38 PM
My tip. Wait for a better dynamics implementation in LW. :D

daz1761
07-23-2011, 04:00 AM
I think your going to have to make more collision objects in order to get a propor result. Use them to fix the weird areas. Lightwave does not have a strong physics system.

Well, that does explain a few things, i was getting worried as i am new to LW thinking i would have to tweek parameters for ages that i wasnt too sure of lol

I suppose if you were doing something like I was in higher detail, you would use a few nulls to finish the wall off?


My tip. Wait for a better dynamics implementation in LW. :D

Sounds logical to me, what software in your opinion have the best physics engines?

Many thanks

skywalker113
07-25-2011, 02:23 AM
Nulls can help tweak things that are hard to do with physics. Blender also does physics that I think are better than Lightwave. Although I have not figured out how to make things stick together and break apart like a wall.

3Ds max does good with physics. Although it cost a fortune unless you can pay for the educational discount.