R E N D E R M A N   S T E P S

If you are reading this page, then you clicked on the Renderman render, and you want to know how to save out .rib files and prebaked animations.

For a text only version of this page please click HERE.

At this point, you should already have what I have been calling your "Middle" branch modeled. Now we are going to create .rib files from that model.

To get started, we will need three versions of our Palm branch.

I simply copy and pasted the SOP tree and changed the values on the bend, twist, and transform on the lower half of the node tree to have 3 seperate branches to save out.

Next, we are going to save out 3 different .ribs in order to have 3 different branches for the proxy. To do this, right click the lowest node on your tree, click on the "Save Geometry" tab. This will bring up a window that asks where and what to save it as. Choose your folder, and make sure to name it " ".rib.

We now have to setup a DelayedReadArchive in the shop level that will read the rib and apply them to whatever geometry I desire.

Make two more and add your .rib files for the Top and Bottom branch to them.

Next you should compile your new shader into a material. I say should because, technically you dont need to, However, compiling your shaders into materials allows them to appear on your Material Palette.

To compile a shader in the shop level:

Highlight the node or tree of nodes you wish to compile

and simply press Shift+C

And now your .rib shaders are conviently in your

Material Palette.

From there, go back to your obj level, and click your geo node. You need to put the new ri_delayedreadarchive nodes in the Procedural shader path.

Geo > Render > Geometry

Rendering at this point should give you a single Palmetto branch that has little curve to its stem and is low to the ground plane.

Now that we have that .rib file applied to a single box, we can begin adding branches.

Create two new geometry nodes by "Copying and Pasting" the Geo Node named "Bottom".

Name one Middle and the other Top to correspond to the .ribs used.

If rendered correctly, you should get something like this.

Now that we know that all of the .rib textures work, we can begin to put together

proxy boxes to make up your deisred number of branches.

This might not be the best way to do this, however, as of the making of this site, I do not have any other solutions that work.

That being said, I think this method is sloppy and cumbersome, but it works. Were going to start with the middle of the plant again, because I feel that with its shape, it is the best option to show differences.

First copy and paste your "Middle" geo node 16 times, so that you have 17 total.

At this point, we need to do a little simple math to figure out the degrees

we wish to rotate around the y-axis in order to give a branch equal spacing.

For this section we have 17 branches that need to be rotated a total of 360 degrees to

form the middle portion of the plant. Therefore, (360/17)= the angle we need, which is ~ 21 degrees.

So highlight all of the "Middle" geo nodes execpt the original, which will stay on the origin,

and enter 21 for the "Rotate-y", or $RY, value.

Finally we're going to parent the geo nodes to each other, that way we do not need to go into each node and change the $RY value. When we highlighted all of the nodes and put 21 in the $RY, that basically gave the node a base number to start at. When you parent them to each other, they take the value from the previous node and add a value they are holding, in our case it is a

$RY value of 21.

If done correctly, your palm section should look like this.

Do the same for both the Top nodes and the Bottom nodes. Use what ever branch number to degree ratio your little heart desires, just remember that it has to equal the full 360 degrees of a circle.

Using the values provided above, I came up with these renders:

Renderman Palm Renders
Houdini Palm Renders
Tutorial Part 3: Finishing Model in Houdini
Tutorial Part 4: Writing a PRMan Shader Using VEX
Tutorial Part 5: Creating .otl in Cutter to Work in Houdini