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daforum
03-15-2018, 05:45 AM
Just seen this from William Vaughan on LinkedIn. Can LightWave do something similar?

http://pushingpoints.com/v2/wp-content/uploads/2017/09/SPG_Size_01.gif

Sensei
03-15-2018, 11:36 PM
In SprayBgPoints (http://modelingpack.trueart.eu)you can spray 1-point polygons on background layer.


https://www.youtube.com/watch?v=P6p-Cm_PFyc

After spraying points, you could use Weight airbrush tool, and use them as particle sources together weight map as particle size..

daforum
03-16-2018, 12:27 PM
Thank you Sensei :thumbsup:

prometheus
03-16-2018, 01:27 PM
In SprayBgPoints (http://modelingpack.trueart.eu)you can spray 1-point polygons on background layer.


https://www.youtube.com/watch?v=P6p-Cm_PFyc

After spraying points, you could use Weight airbrush tool, and use them as particle sources together weight map as particle size..

Thatīs good sensei, but I think itīs quite a different story VS how particles are sprayed with realtime feedback, which I would think is the crucial thing to design it just as you like, not cranking down on your advice though...just pointing out that it is not quite the same.

MonroePoteet
03-16-2018, 03:04 PM
In LW2018, it's possible to get something similar to this type of interactive instance placement, although it's a little more cumbersome to setup in LW and not *quite* so interactive, but it works OK.

The basic concept is to create a Weight Map for each Instanced object on the Ground object in Modeler with their initial Weight at 0.0%. So, for example, if you're going to want to spray a Rock and a Grass Bunch, you'd set up (for example) a RockPlacement weight map and a GrassPlacement weight map with their initial values set to 0%.

In Layout, you set up the Instancer to have Random Rotation and Scaling, and a Weight Map gradient for the Weight specifying the correct Weight Map for each object to be instanced:

140705

You then use F4 to split the Layout screen and bring up Modeler and place it over the right-hand side of the screen (or where convenient for you) and use the Map=>Airbrush to spray the weights for the objects you want:

140706

And, then, the tricky part is assigning a keystroke to the Synchronize Layout command, perhaps CTRL-F12. If you set up LW2018 modeler to have the Layout View and Weight Shade type, you spray onto the view as seen in Layout, press CTRL-F12, and the instances are created. You can clear the map, undo etc. in Modeler. You rotate the desired view in Layout, and then get into Modeler again and the Layout View is updated accordingly.

Setting up the Instancer to Surface, an "appropriate" number of instances, and adjusting the "mid-point" of the positive Gradient allows you to spray using Airbrush and get the desired density.

140707 140708

I've attached the sample scene and objects, but having the shortcut key to Synchronize Layout can't be done automatically in the Scene file. As well, setting up the Layout panes and Modeler panes isn't feasible in the ZIP file!

As I said, more cumbersome to set up, but it actually works pretty well. Having said that, it'd be nice to simply have the Map=>Airbrush function in Layout to change the Weight Maps directly!

mTp

prometheus
03-16-2018, 04:11 PM
what MonroePoteet is doing is also one way to go..yes, and with instances, but as far as I know, there is no way of using sprayed particles and have it in realtime with interactivity, maybe advanced placement is the thing..but very expensive.

If not using instances, there is also another trick, still not possible to get realtime feedback with an airbrush..and itīs only for modeler, you could use dponts Dp_verdure the tree, grass and foliage generator.

In modeler..
if you create a weightmap on your object at zero value, then use weight airbrush at 100 and spray where you want your objects on that, then use the foliage command in dp verdure, and you can choose the weightmap you just created and the objects will be
only on that area, if you just donīt use any leaf object..it will automaticly check your background layer and use whatever is there, so it can be any object, and initially you will interactivly just get a box to showcase the scale and position ..then you apply the foliage with "make foliage"and it will have your background object attached..whatever that is.

http://forums.newtek.com/attachment.php?attachmentid=140710&d=1521238234

raw-m
03-17-2018, 04:07 AM
This can be easily done in Layout if you have 3rd Powers Paint Weight. Setup Instances and feed a weight map into scale, then simply paint on the object with the correct weight map selected.

prometheus
03-17-2018, 04:18 PM
This can be easily done in Layout if you have 3rd Powers Paint Weight. Setup Instances and feed a weight map into scale, then simply paint on the object with the correct weight map selected.

These methods are restricted to actually having the geometry divided enough to enable weight painting, what modo does is most likely just particles actually created on the fly at any object that can be a flat plane even.

what you also can try, that is to use actual particles on the object as instancer, and use a null as scaling ref, or perhaps density ref and use an alpha gradient with distance set to that null, turn on studio live(only in opengl for lw2015, or it will slow down your system too much)
and when you move your null you should be seeing your instances scaled up in reference to how you move your null, preferably you use the density weigth channel and an alpha gradient set to that ref null, so the instances should pop up in realtime only where you move the null, it is still however only instances weight that is generated, you would need a certain amount of particles that covers the whole mesh, and they should be set as generated per frame, and the same amount in particle limit.

with some trickery with raycast, or sticky surface modifier perhaps, you may be able to simulate a brush floating over the surface, but really..the Lw team needs to make this stuff working with painting points or particles directly in layout soon, itīs overdue.

Ztreem
03-17-2018, 06:28 PM
Just seen this from William Vaughan on LinkedIn. Can LightWave do something similar?

http://pushingpoints.com/v2/wp-content/uploads/2017/09/SPG_Size_01.gif

From what I can make out of this video he’s not spraying points on the object, only scaling the objects allready there. That you can kind of do in modeler with airbrush set to morph.

prometheus
03-20-2018, 02:13 PM
From what I can make out of this video he’s not spraying points on the object, only scaling the objects allready there. That you can kind of do in modeler with airbrush set to morph.

better to do in layout (unless it should be made a modeled object) and with nodes on particles, just reference a null in the weight channel with a distance to object gradient in alpha mode(nodes can be used for that as well), and then enter nodes for the scale and use item info (use the null) and then plug that in to scale rotation etc, so you can scale instances with the size control of the null, then just move the null around and the density of instances is based on where you have that null located and how that gradient is set up, and it requires a certain amount of particles, but then again..if you use surface mode instead of particles, you do not even need particles ..so that is maybe better and simpler.

http://forums.newtek.com/attachment.php?attachmentid=140787&d=1521576765