Thursday, April 2, 2015

Day 26 - Smoke, Footprints & Cloth

Billow Smoke

This is the tutorial that I'm working for this billow smoke:
https://www.sidefx.com/index.php?option=com_content&task=view&id=3078&Itemid=407

I'm trying on this billow smoke. Firstly, I'll create a sphere and flatten it, then I'll create a ground plane from the rigid bodies to make them interact. So next, in order to create the billow smoke, I'll go to the pyro fx > billow smoke.


I'll then dive into the autodopnetwork > pyro tab to adjust the settings accordingly then add an area light to make the billow smoke look nicer.



For this exercise, I didn't meet much problem as I think it's more of adjusting the settings correctly to get the correct look of the billow smoke. However, it's very laggy and I need to wait for a longer time to see the results when I wanted to do a flipbook.

This is the directory for this project:
\\MUSHROOMSWISS\test\peishan\billowsmoke

Geometry solver foot prints

This is the tutorial link:
https://www.sidefx.com/index.php?option ... Itemid=132

For this exercise, I'm trying to create this foot print effect when the foot is stepped onto the snow, So firstly to begin, I'll create a grid and a sphere. Selecting the sphere, I'll do an extract on it. Then I select the extracted sphere and grid then go to the modify tab > combine. Now, I'll create an attribcreate for both grid and the object_merge for the sphere. After that, I'll combine both attribcreate using an attribtransfer. I'll then add a group below the attribtransfer.


Next, I'll add in a color node. Now when we keyframe the sphere and make it move, the prints will follow accordingly.


Going back to the grid_object1 node, I'll add in a solver node and duplicate the first set of "group" and "color". 


In the first set of nodes, I'll add in a ray node before the attribtransfer. The ray will make the prints to start to dent down. In the solver node, I'll copy the attribtransfer and ray node that I've created and paste it inside. 


Now, to improve the foot print, I'll reduce the grid rows and columns to 2 each and add a "triangulate2d" node after the grid node. Then I'll import the snow_walk scene which is provide in the tutorial too and add a transform to adjust the orientation of the toon character. Then I'll rename the grid_object1 to snow and change the object_merge inside from sphere to the snow_walk. To make more division on the floor, we'll add in thesubdivide in the snow node.


I didn't meet much problem in this exercise and I find it quite manageable and useful. I've learned how to do the foot print before but I find that this tutorial teaches me a much easier way.

This is the directory for this project:
\\MUSHROOMSWISS\test\peishan\geometrysolver_footprints

Cloth

I went back to explore more about cloth. So after looking at the second tutorial link that I yesterday found, I tried to make the skirt look more like soft material kind by reducing the stiffness of the cloth from 200 to 10. I've also tried to add some lights and a background. I'm trying to find tutorials on how to use basic shapes to create out different types of clothes as I find it quite interesting to create clothes out for that character. I found one checkered cloth texture and try to paste the texture on it. So this is the current results. I'll try to render out the movie file for the billow smoke and cloth to see the effect and post here.



Wednesday, April 1, 2015

Day 25 - Cloth & Particles Spray

Cloth

Today I tried on some cloth simulation. 
These are the two tutorial links:
https://www.sidefx.com/index.php?option ... Itemid=132
https://www.sidefx.com/index.php?option ... Itemid=132


Firstly, I went to the Mixamo website to download the free character with animation. I downloaded it as an FBX file and I'll import it to Houdini. To group the animation together and cleaning things up, I'll first select the body and a "body_geo" with a set of nodes will pop up. I'll go to the take list. I'll merge the mixamo_com in the take list to the main and delete the other nodes in the take list except the main. So now, my animation will work just fine. To resize it, I'll first select the body and go to the Modify tab > extract. After I do so, an "object_merge" will appear. I'll rename that node to "body" and inside that geo, I'll put in a transform node and scale it down to 0.1.



I'll do the same for the other 3 parts which is the hair, left eye and right eye by duplicating the "body" node 3 more times. Next, we'll export the geometry by creating a ROP output driver in each of the node and render. 



So now everything is completed, I'll go and create a new file and import in the geometry that I just rendered. I'll now drop down a mantra surface and change the specular color to something dark. After that, when we downloaded the model down using FBX file and extract it for the first time, they'll have some default material coming together. So I'll assign that material with it.



I'll now start to create the skirt for my character. Firstly, I'll start by creating a circle and resize it. Then I'll go and do a polyextrude and do some alter to the settings. In order to achieve more details, I'll put in a subdivide for the skirt polygon. Then I'll adjust the radius and center accordingly.



After that, I'll color the skirt by using a mantrasurface.



So now, I'll go to the cloth tab and select the body, then click on the cloth body collider. Then I'll select the skirt and cloth on cloth object. So now the simulation is created. However, the skirt is not attach with the body and it looks weird. So I'll use the attach to body tool to attach both together. I'll select only the top part of the skirt.




So now the cloth simulation of the skirt is done. I enjoyed doing this tutorial as I find it quite fun to help the character to create some clothes for her. I've also learned how to use basic shapes and gradually create out some cloth.




This is the directory for this project:
\\MUSHROOMSWISS\test\peishan\Mixamo_houdinicloth

Particles Spray On Waves

I tried on another tutorials whereby we can create particles spray on waves.
This is the link for the tutorial: 
https://www.sidefx.com/index.php?option ... Itemid=166
For this tutorial, I'll first have to create a grid, changing it to a nurbs. Then I'll apply a soft transform in the middle of the grid points and adjust it.


I'll then add in a mountain node and created out a network box to clean up my network. Next, I'll go and create three curves that will be used as an isobars.



I'll apply a transform after the merge node to do the keyframing for the isobars to animate and move.



After that, I'll add in a convert node after the mountain to convert it into a polygon. Then, for the other side of the transform node, I'll add in a color node and make it red color. Then I'll combine both nodes using an attribtransfer.



I'll now group the points together by creating a group node. In the group node, I'll create an expression of $CB < 0.8



I'll then add in a "popnetwork" and dive inside to create a source. Then I'll adjust some of the settings and this is the final result for this exercise.





This is the directory for this project:
\\MUSHROOMSWISS\test\peishan\particlesprayonwaves