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.

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

Day 24 - Avalanche Previsualization

Avalanche Previsualization

Today I tried out this tutorial, https://www.sidefx.com/index.php?option=com_content&task=view&id=1221&Itemid=262

So basically, I'm supposed to create this collision between this slope and boulders. Firstly, I created out the slope by creating out a grid and making it to rotate on x-axis by 58 degrees, increase the rows 15 by 15 and scale 4 by 1 by 3. After that, I dived into the "slope" node and create a mountain node. I increased the height to 1.3

Next, I'll go and create the "boulders". I'll first create another grid, scale it 3.3 by 1 by 0.5 and change the rows by columns to 2 by 2. I'll then change translate y-axis to 13 and z-axis to -1.5.

Lastly, I'll go and create another box as my "source_boulders"

I'll start and make the "slope" object to be a "Rigid bodies > Terrain Object" then I'll make the "boulders" a RBD point object. Then I'll select the box as my instance. For this, when I'm selecting the RBD point object, I'll have to click on the RBD point object instead of the RBD packed object.

After that, I'll go back to "source_boulders" and create a color and null node. After that, I'll go back to the "slope" node to create an object merge for my boulders. Then I'll go and create out an "attribtransfer" node to combine my "attribcreate" and "object_merge". So after that, I'll add a group under "attribtransfer" and named it snow and at the filter expression, I'll add in this filter expression "$CB < 0.8"

Next, I'll create a popnet, dive inside to create a source and interact pop. So as to create the particle simulation to appear when my boxes started to fall down. I've also went to the "source_boulder" node to create a tube and switch so that I can toggle in between boxes and tubes to create more variables. So this is my final work.

However, I still couldn't make the particles to appear after my boxes dropped off. The particles will appear before my boxes drop off. I tried to fix it but I haven't get to solve it. But other than that, other things that is in this animation works well.

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

Day 23 - Flip Fluid Render & Working With Noises

Flip Fluid

Last week, I did out a flip fluid and I went to test render it out. This is how it would look like but I think that it can be improve.

Working With Noises

Today, I tried out the tutorial whereby it's about noises.
This is the tutorial link:
https://www.sidefx.com/index.php?option=com_content&task=view&id=2567&Itemid=132

Firstly, I tried out with the pointwrangle node. I learned that we can refer to vopsop node if we are unsure what is the expression we should use in the pointwrangle. I created out this random wave bar lines using the expression.

By inserting this "Frame" node inside the VEXpression, it allows me to create a short animation whereby when it's playing, the random bar lines will start to move.
We can actually create other pattern of the bar line by changing the VEXpression.

So after that, I went through this tutorial whereby Mr Ari taught about the different noises waveforms. I screenshot some of the notes down. This is the 2D examples for examining the waveforms.

This is the 3D examples.

I went on to explore some simple vopsop nodes that I can apply to create basic mountain shader.

By swapping some of the nodes, we can create different effects out.

We can also use a switch node to check out different noise waveform even easier by browsing the motion view:

After that, I went on to do one of the example whereby I'm suppose to create this noise and I've made a switch for different geometry so that I can switch and look at the noise being placed on different geo such as "torus", "sphere" and "grid".

Basically, I'm following this steps and created out these nodes to form out.

This is my overall workflow.

After I created out this noise workflow, I'm able to switch this noise to different geometry.

So this is the final look of it.

Day 20 - Flip Fluid & Procedural Animation Text

Flip Fluid

I found this flip fluid tutorial in the houdini website so I decided to give it a try. 
Here's the link:
https://www.sidefx.com/index.php?option=com_content&task=view&id=2157&Itemid=262
Firstly, I started to create out a grid then selecting the primitives, I did some polyextrude. After that, in order to clean up the bottom edges of the landscape that we are using as our base for the water to fall down, I selected the edges and loop it then I'll edit and scale it down. So when the edges are still selected, I'll add in a polycap and make the landscape geo that I created into a static object.

I've also did some changes after I made the landscape geo into a static object by diving into the autodopnetwork and rename the static object as landscape so that it will be clear enough. Then I'll turn on the show collision guide geometry and increase the uniform division to 100. 

Next, I went on to create an emitter for the water fluid using a grid. I'll then select the grid then select the emit particles fluid.

I'll dive into that autodopnetwork and selecting the "flipsolver1", I'll adjust the box till it's only covering the landscape.

I want the fluid to flow down and got deleted, not accumulating particles inside so I'll go to the flipfluidobject > properties > initial data and tick on closed boundaries and uncheck the "+z axis".
Next, I go to my emittergeo and add a mountain and vopsop inside.

In the vopsop, I'll add in this nodes and now, my flip fluid is in this state.

I've also adjusted the height of the highest peak of my landscape to make the fluid collision to have more impact.

After that, I went to export the particles out and isolate the "particles","vel" and "surface". After that I created a vopsop inside the particle_fluid to create the randomness of the particles flowing.

I went back to the particle_fluid and create another delete node, changing the entity > points and operation > delete by expression. Then I'll add in this expression in the filter expression: "$CR<0.8" to see the filtered particles.

I'll create another dopnetwork and add a popobject and a popsolver. Inside the popsolver, I'll add a source and adjust the settings accordingly.

I'll make the landscape into a static object after I go back to the landscape geo and make the visability tab to polycap. I'll then dive back to the spraysim > popsolver > voppop and create out these nodes.

After that, I've also created out another geo for the spray and in it, I've created dopimport and box respectively. So this is the end result of my flip fluid, I'll do a test render out and post here.

This is the directory for my project:
\\MUSHROOMSWISS\test\peishan\flipfluid_files

Procedural Animation Text

Tutorial link: https://vimeo.com/17039552
I found this tutorial in the houdini website too however, I couldn't really follow the tutorial well and I can't find any reference file for that. But throughout this tutorial, I learned a new tool which is "foreach". It looks something like a copy/instance node and it's quite useful. We can duplicate objects using either primitive/points or other options too. 

This is the directory for my project:
\\MUSHROOMSWISS\test\peishan\proceduraltextanimation