This is a basic intro to wrangles and will cover how to control and understand integer, float and vector values. Will also introduce geometry spread sheets and how to manipulate variables. - Integer : Whole number - for example: 1, 2 , 3 - Float : Decimal numbers - for example : 1.1, 2.2, 3.3 - Vector : Three values - x y z - for example: { 1, 2, 3 } - To create our first attribute we will declare a value: i@atti = 1; // This means i stands for integer, @atti can be anything, the name you wish the attribute to have. - Use the geometry spread sheet to analize the input values on the wrangle. (0:04:09:16) - f@attf = 1.1; // This means float and the name of the attribute. You can see we will get decimals here ( 0:05:11:22 ) - v@attv = { 1, 2, 3 }; // This will get us the vector values on our geo spread sheet. Heres is the code: i@atti = 1; f@attf = 1.1; v@attv = { 1, 2, 3 }; // Note this double slash means its a comment so houdini doesent read this line of code. And houdini starts counting from 0, just like computer science. - Variable; int vara = 1; float varb = 1.1; vector varc = { 1,1,1 }; Examples for manipulating normals: @N = {1,0,0}; per vector manipulationf: @N.x = 1; and you can also do @N.x, @N.y, @N.z // Houdini understands a set of global attributes that have already been declared as integer, vector or floats. This are set values inside of houdini so we dont need to declare this global attributes. Example of global attributes: P = vector = point position N = vector = normal direction v = vector = velocity id = int = uniqu element ID pscale = float = uniform scale scale = vector = scale non uniform

Uisng voronoi fracture and material fracture. - scatter points onto the geo or points from volume. Points from volume prefered because it creates points inside of your geo. - Jitter the points so that you can scatter them randomly - Plug the geo onto the right side of the voronoi and points into the left. - Explode view will show you waht you have and how its been f ractured. - Voronoi breaks the geo based on the position of the points. The more points, the more pieces that you will have. - In the Voronoi, you can export different groups, such as inside or outside groups. (0:03:08:17) you can see an example of inside and outside pieces coloring here. - You can use this group for subidiving, different texture and other control. - Theres options to output different attributes as well. - Check out (0:04:47:14) to understand how to control the density in specific places of the amount of broken pieces. - Material fracture is the same thing but much more robust. - No need to use the points in the material fracture because it has the functionality already built inside. You can control the amount of points your scatterng inside of the material fracture. (0:06:13:25) - The noise controls the position of this points, therefore it controls the variation of the position from the broken pieces. - You have the ability to add multiple layers of fracture. (0:07:30:24) It breaks this broken pieces into more small pieces. -The chipping will shatter them in slices / chipping adds a lot of detail. - Control the interior and edge detail to your material fracture. This adds a noise and allows you to create deformation of the geo inside pieces. (0:09:10:18) - The constraints allow syou to glue pieces for rbd simulations. - Note you can fracture different kinds of default setups. Such as ready to go concrete, glass or wood. (0:09:10:28)

This are basic ways you can make the most out of the polyextrude node. Will cover the main parameters and good practices, such as grouping with extrusions so that you can make your setups procedural and efficient. - Make sure you are using polygons so that we have subdivisions to extrude - Polyextrude is the node we will be using - To extrude individual elements choose the divide info option below group. - Inset allows us to reduce the size of extruded face - You can alos twist and inrease its subdivisions to create subdivided twisted geo. - Note how the same setup works with differente geo. (0:01:54:05) - The extrude options gives us ability to extrude groups and output different parts. - Enable the output back to make sure your extrusions have closed back. (0:04:46:23) - The spline controls is awesome fro adjusting the thickness and twist based on prebuilt spline ramps. - Extruding based on groups is procedural and effective. Once grouped you can pick the name of the group inside the extrude sop.(0:04:23:14) - Extrusion based on curve will allow you to control the path of the extrusion. (0:07:02:16) - (0:07:47:24) Shows you an example of how to mix both the curve extrusion and the thickness ramp control together effectively. - (0:08:57:21) Heres how to mix extrusions with vdbs and an idea of how to make growing fx.

Learn what fit range means and the power of the curve u attribute. Will cover the reason for you to use fit range functions and the importnace of remapping values. The curve sop is essentialy the same thing as splines in c4d. You can pick what kind of curve you want to have. We are using the nurves curve. Then converting nurves back into polygons and resampling it. - Resample: This is great for reorganizing the points on your curve, you can increase or decreade them, controlling the level of detail and smoothness. - Note that in the resample, we are also enabling the curveu attribute. (0:02:28:10) = The color sop lets us visualize what we are doing when ramping from attribute and writing down curve u attribute. (0:02:55:07) = Polywire, we are typing our curveu to control our width in the wire radius. So the curve u gives us a value that goes from white to black from one edge of the spline to the other edge. If we control our radius based on this value, we will get one side thick and thin on the other end. = @curveu*.3 : Will make the thicker side thinner. but it makes the entire thing thinner. We cant control the thickness in an easy way and thats why we use fit functions. - (0:04:28:02) Shows you a solution for resolving this issue. Creating attribute create: Name this attribute width and give it a value of @curveu - This tells houdini that the value is going to be calculated based on our value, in other words curveu = width - So then when we add the polywire and we type in @width it will give us the width based on the curve u. - Now on (0:05:17:00) We type the fit function on our attribute create value. So we know our current value is curveu, now we will control the curveu values to fit them like this: fit(@curveu, 0,1,.5,.3) - (0:05:25:16) Explains how the the fit funciton works. We state that we want to fit. then the parenthesis says that we wan the curveu attribute to be fit. And the first two numers state to fit the 0 and 1 values. And the second two values state what we want the new values to be. - With this setup, you can now give the beginning and end of the curve a number you desire. - (0:06:21:10) Recap of process, quick follow for final result.

This is an intro session on basic particle understdings. This is aimed to help you understand what particles really are and how we can turn points or geo into particles inside popnetwork. It will also cover the main parameters inside a popnet and introduce you to what a popnetwork is. Notes: - Popnetwork is the main default setup for particles. - Popnet contains: Source: which is what refers to the source outside the network Popobject: which refers to the kind of object this dopnet is using - in this case pops for particles. Popsolver: The main solver setup where we plug things in to solve (run sim) Merge: it defaults with a merge - Remember that particles are simply points. Popnet allows us to control the points and when they move, we refer to them as particles. Popsource: - Includes the source. Which can have scatter onto surface. This makes particles appear onto the surface. Almost as an animated scatter points onto surface. - Popnet defaults to no force affecting the particles. So this is why we use a popforce ( this is unless you have added velocity to the particles before bringing it into the popnet ) - (0:04:24:27) Will show you how to make particle begin to be born from existing points. This is if you want particles to exist from points and not from the geo. - Birth: you can use the impulse activation to control when particles are born, for how many frames. - Attributes: you can control any attribute you are brining in, for example ( 0:06:42:20 ) will show you how to compute velocity of your animation before you bring it into the popnet. In this case we also enable this attribute inside our popnets attribute controller and use the inherited velocity. - Popdrag: makes the fx you build feel a bit more slow motion. - Use file cache after you have your setup diled inn. - After the sim you can see all the attributes that are created. - Age, airresist ect - all of this attributes are controllable - Use a color and ramp by attribute to visualize the attributes fx. Refer to (0:10:46:09) In order to see an example of how I am using velocity to color our particles using a ramp of color. This makes particles change color based on our v.

We are going to learn how to use RBDs in creative ways. For this shot, you will learn how to manipulate leafs of trees in a beautiful, artistic way. Will also break down the shot and show you how it was setup in different networks. Notes: - Clip node is great for cleaning geo - Transform : move centroid to origin helps get things in the 0 axis. - Note how im clipping main parts of the geometry and isolating them to build different architectural pieces. - I use a null ( with OUT_ and then a name ) Then a merge object to reference it and bringing it into different parts of the network. - Use the select "3d connected geometry" to isolate and select pieces of geo easier. - The tree comes in as an alembic file - Then converted to polygons - It is isolated into two different parts / bark and leafs - The tree was built using speed tree - You want to use the bark as the collider and the leafs as the active rbd - I didnt sim allthe lefs, I isolated some of them to be the ones that move. - Make sure you set it to a proper scale value - houdini sims with proper real life values - Uv quick shade I use to test my diffuse channels on the textures and making sure my uvs are properly built. - The object that will be simmed, use an assemble to pack it and letting houdini know its all individual leafs. - Inside dops - You want to use a rigidbodysolver. - Use RbdPacked Ojbect with a popforce - Then use a static object as collider merged towards the right side after the rigid body solver has solved the active pieces. ( refer to 0:10:27:05 ) - You want to cache this after the simulation - If you want to chane the movement of the leafs, play with the pop forces amplitude and frequency to control its forces. - its cool to bring the floor but if you dont see the floor, there is no need to sim and calculate this extra info. - Then merge this sim to the actual tree bark - Position the tree in the right place of the scene and create a delete with a bounding box to delete all the pieces that leave this limit. This helps with performacn

This is an intro onto vdbs. Learn some good vdb practices, tips and tricks to help you undertand its advantages and when it is a good time to use.

Tips on how to control the axis of your objects in houdini. Will cover how to do this manually, procedurally and simple script snips that will allow for incredible control over any setups axis. This is very useful for c4d users whom use the axis center option. Heres how to take that to another level.