Daily Updates (19th July)

Lesson 12 :

In the first part of this lesson, I learn how to add layers in the mantra also render float value like $AGE, $LIFE by creating a parameter in the material shader builder and name in the same name the attributes is being created.

To render different layers, extra image plane have to be create so we could choose which render layers we want to see.

In the material shader, I need to create parameter with the same name I named my attributes.

In the material shader, I need to create parameter with the same name I named my attributes.

Creating attributes and viewing them on a image plane.

$LIFE is a percentage from 0 (Birth) to 1 so the render below is representing the value of $LIFE of the particles showing by colors, 0 being black and 1 being white.

If i press I on the keyboard, I get a look up table where I get to see the color values.

Toon Shader

In the next part of the lesson, I learn how to create a toon shader. A simple toon shader will be just using the the two tone node in the shop network

But we are also able to edit the parameters, for example, mixing it with textures.   In order for us to adjust how much color of texture we want, we add a parameter node and insert in to the bias amount of the color mix so we could control how much texture or color we want.

In order to get ready for compositing, we create another parameter inside the shader and label is obj id. This is to ensure that each geo is masked out seperately.

Under the mantra node, we create a new image plane and name the same name obj id in order for to render the mask in a seperate layer.

So when you render and view the obj id layer at first you will get all white, you have to click "adapt to full pixel range" to see the seperate mask.

In the tutorial, wren node is used. It can be found in the out level and it is used to render wireframe of the geo. Apparently apprentice version houdini is disabled and i cannot use the node.

So since before compositing, we had a layer called obj id and in obj id my grid and teapot have different values and we can call the values back into compositing by using the limit node and mask out the geo seperately.

The teapot was given a value of 5 in obj id. So by using the limit node, I can change the lower and upper limit to 5 and get the alpha of the teapot. But before that, I have to put a channelcopy node so i can extract the obj id layer. By doing this I can just edit the teapot itself without affecting the grid.

And by multiplying back to the original image, we are able to see the changes made. I am glad that the compositing side of houdini is not difficult to use as it is quite similar with compositing softwares like Nuke. I will definitely explore more on compositing.