4. Setting up a material for the dynamic material

-

Before we start programming our dynamic material, we need to create a static material. This material will be used to create our dynamic material. You can create a new material by going to the “Content” folder in the Content Browser. Right click in the content browser and click on “Material”.

Img 10, Creating a material


By double clicking on our material, a new window will open where we can edit our material. First let’s create a vector parameter. Right click on the grid and type “Vector Parameter”.

Img 11, Searching and selecting the vector parameter node


Click on the “Vector Parameter” option. A new node will appear. By clicking on the node, you can edit the details of the node. For us, it’s important to set a clear parameter name. The parameter name will be used for our code later. I’ve called my node “EmissionColor”, because this parameter is going to determine what color our dynamic material is going to emit.

Img 12, Setting the vector parameter name


Let’s create a scalar parameter to get control over the emission strength. Again, right click on the grid and type “Scalar Parameter”. Click on the “ScalarParameter” option to create a scalar parameter node.

Img 13, Searching and selecting the scalar parameter node


We also need to give our scalar parameter a parameter name. I’ve called my parameter “EmissionStrength”.

Img 14, Setting the scalar parameter name


We need a multiply node to combine our parameters for the emission output of our material. Right click on the grid, type in “Multiply” and click on the “Multiply” option to create the multiply node.

Img 15, Creating a multiply node


Connect all nodes as in image 16. You can connect the nodes, by holding your left mouse button on a slot and dragging it to another slot.

Img 16, Connecting all nodes


Save your material, by clicking on save in the left top corner of the window. The material is now ready to be used for our dynamic material.

Popular posts from this blog

6. Creating and editing the dynamic material

-
Image
Before we can create our dynamic material, we need to find our static mesh component that contains our material. Img 23, Code of finding our static mesh component and creating and setting our dynamic mesh With the “GetComponentByClass()” function we are asking UE4 to return to us the first component object defined within the round brackets. We want to receive our static mesh component, so we use “UStaticMeshComponent::StaticClass()”. The function returns a “UComponent*”. With the “Cast<T>()” function we can convert the returned object between the round brackets to our class defined in position of “T”.  We use the “IsValid()” function as a security to make sure that the cast has been executed successfully. If the cast has failed and we were to try to access an empty pointer, our game would instantly crash. Within the if-statement we put the rest of our code. Line 25 on image 23 creates a dynamic material and assigns it to our pointer. Within the function we use “SMC->GetMat...
Read more

5. Constructing a blueprint

-
Image
We need a blueprint where we can combine our assets. A blueprint will allow us to create multiple instances that we can place in our level. You can create a blueprint in the same way as creating a material. Go to the Content Browser, right click in the content and select “Blueprint Class”. Img 17, Creating a blueprint class A new window opens. A blueprint is by UE4 seen as a type of class. We need our blueprint to inherit our class “DMObject” in order for our blueprint to have our code. Open “All Classes” at the bottom of the window and type in your class, I used “DMObject”. Click on your option to continue. Img 18, Creating a BP that inherits “DMObject” Open the newly created blueprint. We need to add a component that can hold a mesh with our material. Click on “+Add Component” in the left upper corner. A window will pop-up with a list of predefined components. Click on “Static Mesh” to create a static mesh component. Img 19, Adding a static mesh component Let’s choose a mesh that can...
Read more

8. Reading parameters of the dynamic material

-
Image
For creating different types of effects it can be very useful to read the parameters of a dynamic material. Let's read and output our emission color right after the effect we created earlier. Img 30, Reading and outputting emission color For our reading function, we need to create a variable placeholder that can contain the information of our color. You can see on line 38 of image 30 that I’ve created a FLinearColor placeholder called “ReadVector”. To read a vector parameter, we need to use the “GetVectorParameterValue()” function contained in our dynamic material. The function needs the parameter name, which we declare in the first parameter slot. In the second parameter slot we put our “ReadVector” placeholder. Next, we want to output our emission color to the output log of UE4. That way we can test if our code works. On line 40 of image 30 you can see how to do that. I am outputting the name of the object, following the read color. Reading the scalar parameter value is similar. ...
Read more