Rendering with particles

Announcements, requests and support regarding the Blender Indigo export script
Post Reply
13 posts • Page 1 of 1
abecrow
Posts: 7
Joined: Mon Apr 29, 2013 11:04 am
Location: France

Rendering with particles

Post by abecrow » Tue May 07, 2013 10:27 pm

Hello,

I have a little problem with blender and Indigo. Let me explain my scene:

On an empty scene (just a camera and a light), I created an object of type "plane" to simulate the ground. I applies a brown material such as "diffuse" and I add another material green.

Keeping the selected object, I add a particle system with "Hair" type, I made ​​my adjustment to have a proper grass in Blender.

My problem is when rendering in Indigo, I see the ground, but not the grass, then with rendering blender everything is perfect.

Is there a way that the grass is rendered in Indigo ? If so, how ?

Thanks,
Attachments
blender.jpg
Scene in Blender

User avatar
Headroom
Indigo 100
Posts: 989
Joined: Wed Aug 08, 2007 1:07 pm
Location: Spartanburg, SC, USA

Rendering with particles

Post by Headroom » Tue May 07, 2013 10:43 pm

Yes. Don't use hair ;-)

Use a simple grass object modeled in blender and then use the particle system to instance it. StompinTom posted this little tutorial ages ago and I am not even sure if it still opens up in Blender that does exactly that.

http://www.indigorenderer.com/forum/vie ... =19&t=8846

The hair system in Blender is specifically tied to the strand renderer in Blender and I don't think, it can be used with any external render engine, be it Indigo, Luxrender, Yafaray etc.

Once you've successfully create the first grass you can use with maps to distribute it unevenly etc. works pretty cool actually.
iMac 2.93 GHz Quad Core i7. 12 GB memory
ATI Radeon HD 5750M 1024 MB
OS X 10.10.3 Yosemite
Blender 2.72, Blendigo 3.8.25, Indigo 3.8.26

Trippy Lighting LLC - Colorful LED lighting systems
High Power RGB LED driver - Blog

User avatar
aleksandera
Posts: 378
Joined: Fri Sep 15, 2006 10:49 pm
Location: Slovenia

Re: Rendering with particles

Post by aleksandera » Wed May 08, 2013 12:08 am

It would be nice to have something like this in Blender exporter :oops:
http://xaotherion.deviantart.com/art/Lu ... -178646164

abecrow
Posts: 7
Joined: Mon Apr 29, 2013 11:04 am
Location: France

Re: Rendering with particles

Post by abecrow » Wed May 08, 2013 12:34 am

Headroom wrote:Yes. Don't use hair ;-)

Use a simple grass object modeled in blender and then use the particle system to instance it. StompinTom posted this little tutorial ages ago and I am not even sure if it still opens up in Blender that does exactly that.

http://www.indigorenderer.com/forum/vie ... =19&t=8846

The hair system in Blender is specifically tied to the strand renderer in Blender and I don't think, it can be used with any external render engine, be it Indigo, Luxrender, Yafaray etc.

Once you've successfully create the first grass you can use with maps to distribute it unevenly etc. works pretty cool actually.

It work thank you !

User avatar
Zom-B
1st Place 100
Posts: 4656
Joined: Tue Jul 04, 2006 4:18 pm
Location: ´'`\_(ò_Ó)_/´'`
Contact:

Re: Rendering with particles

Post by Zom-B » Wed May 08, 2013 12:35 am

aleksandera wrote:It would be nice to have something like this in Blender exporter :oops:
http://xaotherion.deviantart.com/art/Lu ... -178646164
Seems that this was simply converted to polygons on export (therefor the long export time and RAM need!).
polygonmanufaktur.de

StompinTom
Indigo 100
Posts: 1820
Joined: Mon Sep 04, 2006 3:33 pm

Re: Rendering with particles

Post by StompinTom » Wed May 08, 2013 1:53 am

You get more control and variety if you instance the grass yourself instead of using a converted hair system. Grass doesn't look like hair, and there are many other little plants mixed in with the blades of grass in any typical lawn. With instancing you can use size and density maps as well, something which is incredibly useful.

Good to see my little tutorial still works.

User avatar
CTZn
Posts: 7240
Joined: Thu Nov 16, 2006 4:34 pm
Location: Paris, France

Re: Rendering with particles

Post by CTZn » Wed May 08, 2013 2:44 am

StompinTom wrote:With instancing you can use size and density maps as well, something which is incredibly useful.
How is this implemented into the exproter ? Using indigoScatter or particles coordinates ?
obsolete asset

User avatar
Polinalkrimizei
Posts: 632
Joined: Sat May 02, 2009 6:59 am

Re: Rendering with particles

Post by Polinalkrimizei » Wed May 08, 2013 6:17 am

Blender spreads the grass meshes around the surface as you wish, e.g. controlled by a density map. Blendigo exports the meshes as instances afaik, and most of the time three or four light meshes are enough.

User avatar
CTZn
Posts: 7240
Joined: Thu Nov 16, 2006 4:34 pm
Location: Paris, France

Re: Rendering with particles

Post by CTZn » Wed May 08, 2013 7:13 am

Thanks polinalkrimizei.
obsolete asset

StompinTom
Indigo 100
Posts: 1820
Joined: Mon Sep 04, 2006 3:33 pm

Re: Rendering with particles

Post by StompinTom » Wed May 08, 2013 12:35 pm

Polinalkrimizei wrote:Blender spreads the grass meshes around the surface as you wish, e.g. controlled by a density map. Blendigo exports the meshes as instances afaik, and most of the time three or four light meshes are enough.
Yes, that's correct. It requires you to switch to Blender Internal to reveal the texture settings, though, something that the Blendigo devs may want to look into freeing up. Activating Indigo hides a lot of the texture functionality that Blender otherwise has.

User avatar
CTZn
Posts: 7240
Joined: Thu Nov 16, 2006 4:34 pm
Location: Paris, France

Re: Rendering with particles

Post by CTZn » Thu May 09, 2013 10:42 am

StompinTom wrote:
Polinalkrimizei wrote:Blender spreads the grass meshes around the surface as you wish, e.g. controlled by a density map. Blendigo exports the meshes as instances afaik, and most of the time three or four light meshes are enough.
Yes, that's correct. It requires you to switch to Blender Internal to reveal the texture settings, though, something that the Blendigo devs may want to look into freeing up. Activating Indigo hides a lot of the texture functionality that Blender otherwise has.
In the case of random scattering over a surface, the particle system could be translated to an indigo_scatter node, density(/size iirc) texture/shader included.

The density/particle count would be preserved but the particle placements would be different. Exports blind fast.

edit: I checked and the instance size does not seem applicable using polygonal meshes but parametric surfaces.
edit2: actually the node name is scatter.
edit3: my XML reference, there's no further data required to scatter 1000 objects over a surface (using a shader):

Code: Select all

  <scatter>
    <name>the scatter</name>
    <geometry_uid>1000</geometry_uid>
    <material_uid>3000</material_uid>
    <num>1000</num>
    <shader>
           <![CDATA[   
def evalScale(int index) real :
  0.1 # 0.1 * (0.5 + gridNoise(real(index)))	]]>
    </shader>
    <target_object_uid>2000</target_object_uid>
  </scatter>
obsolete asset

StompinTom
Indigo 100
Posts: 1820
Joined: Mon Sep 04, 2006 3:33 pm

Re: Rendering with particles

Post by StompinTom » Fri May 10, 2013 1:07 am

CTZn wrote:
StompinTom wrote:
Polinalkrimizei wrote:Blender spreads the grass meshes around the surface as you wish, e.g. controlled by a density map. Blendigo exports the meshes as instances afaik, and most of the time three or four light meshes are enough.
Yes, that's correct. It requires you to switch to Blender Internal to reveal the texture settings, though, something that the Blendigo devs may want to look into freeing up. Activating Indigo hides a lot of the texture functionality that Blender otherwise has.
In the case of random scattering over a surface, the particle system could be translated to an indigo_scatter node, density(/size iirc) texture/shader included.

The density/particle count would be preserved but the particle placements would be different. Exports blind fast.

edit: I checked and the instance size does not seem applicable using polygonal meshes but parametric surfaces.
edit2: actually the node name is scatter.
edit3: my XML reference, there's no further data required to scatter 1000 objects over a surface (using a shader):

Code: Select all

  <scatter>
    <name>the scatter</name>
    <geometry_uid>1000</geometry_uid>
    <material_uid>3000</material_uid>
    <num>1000</num>
    <shader>
           <![CDATA[   
def evalScale(int index) real :
  0.1 # 0.1 * (0.5 + gridNoise(real(index)))	]]>
    </shader>
    <target_object_uid>2000</target_object_uid>
  </scatter>
This would be something that would be extremely useful with PyNodes within Blender! If we could have some Indigo material nodes with things like scatter, ISL textures, etc., it could really simplify / speedup things like particle export / distribution.

User avatar
SaphireS
Indigo 100
Posts: 134
Joined: Tue May 05, 2009 9:06 am
Location: Austria
Contact:

Re: Rendering with particles

Post by SaphireS » Mon May 13, 2013 6:35 pm

StompinTom wrote:
CTZn wrote:.../quote]

This would be something that would be extremely useful with PyNodes within Blender! If we could have some Indigo material nodes with things like scatter, ISL textures, etc., it could really simplify / speedup things like particle export / distribution.
+1 for PyNode support (Blender 2.67 incl. PyNodes is officially released since a few days) ;)
Your ad here!

Post Reply
13 posts • Page 1 of 1

Who is online

Users browsing this forum: No registered users and 1 guest