Next steps

Simplifying the Project View

By default, the Project View can look intimidating. The list contains many files and folders, and you haven’t even started writing a program! But we can simplify it by hiding files that are not Kotlin programs.

First, let’s enable some new scopes for the Project View:

  • Make the Gradle panel visible by clicking on the Gradle elephant on the right side of the screen.
  • In the panel that shows up, double-click on openrndr-template > Tasks > openrndr > "add IDE file scopes".
  • Hide the Gradle panel by clicking on the elephant again.

After running the add IDE file scopes task, let’s enable the scope that shows code files:

  • Click on Project ⌵ at the top-left of the Project View.
  • Choose ★ Code at the bottom of the list.

Only two Kotlin files should be listed, everything else is now hidden. Isn’t that a relief?

You can always switch back to the Project scope to see all files or switch to one of the others. For instance, the ★ Media scope will display only sound, image and video files from your project.

Multiple programs in one project

By default, the openrndr-template project comes with two programs. One is called TemplateProgram.kt and the other TemplateLiveProgram.kt.

The second one provides live-coding! If you run that program by clicking on the green triangle next to fun main(), any changes you make to the code will be visible in the running program after you save your changes. No need to stop and start the program.

But you are not limited to two programs, of course. In the Project View on the left, you can copy and paste .kt files (using keyboard shortcuts or the mouse). IntelliJ IDEA will ask you to name the new file (the name must start with an Upper-Case letter). It will also ask whether you want to add the new file to Git. It’s fine to click Cancel.

If you created a third .kt file, make some changes to it and then click the green triangle next to fun main() to run it.

All your Kotlin programs must be placed under src/main/kotlin, otherwise they won’t run.

Note: at the top of the window, there is also a green triangle to run programs. By default, clicking that green triangle will re-run the last program you ran, no matter which file you are editing now. This can be surprising when you start editing a different program in your project. For a more intuitive behavior, click on the drop-down on the left of the triangle and select Current File. After this change, the top green triangle will run whatever program you are currently editing.

import statements

OPENRNDR is very modular. Not every possible feature is available by default: to make classes available, they need to be “imported”. For example, if we want to create a Circle object, we need to add a line at the top of the program that imports the Circle class. After doing this, the compiler will understand what a Circle is. Fortunately, we do not need to type such import lines by hand. Let’s see how IntelliJ IDEA helps with this.

Inside the extend { ... } block, go ahead and type val v = Vector3. When you do this, a floating dialog should appear. What this dialog is doing is asking you “which Vector3 do you mean?”. See, different classes may provide something that sounds like a Vector3. Some of these classes can be part of OPENRNDR, and other classes may be provided by Java or other frameworks.

The one we are looking for is “Vector3 (org.openrndr.math)”. If it is highlighted in that floating dialog, press the ENTER key. This will add the necessary import statement to the beginning of the file, making Vector3 available for you. If the highlighted item was not the one we were looking for, press the UP and DOWN arrow keys to choose the right one, then press ENTER.

If you accidentally import the wrong one, you can undo, or you can also manually delete the import from the top of the file.

When an import is missing, the unrecognized word will be highlighted in red. Let’s try this. Delete any Vector3 related imports from the top of the file. The Vector3 word will be highlighted as an error. When this happens, we can automatically import the right class by clicking the word (highlighted in red), then press ALT+ENTER (or Command+ENTER on Mac). A tool tip will show up letting you choose the right import to add.

IntelliJ IDEA cleanup tips

In IntelliJ IDEA, you can double-tap the SHIFT key to open a global search tool that will find whatever you type in your source code, but also in the program settings, menus and actions you can perform.

Let’s try it:

  • Double-tap SHIFT and type optimize. In the search results choose optimize imports. This will remove no longer used import statements from the beginning of your program.

  • Double-tap SHIFT and type reformat. In the search results choose reformat code. This will tidy up the spacing and indentation of your program.

What’s next?

At this point you are likely interested in how this program is structured. The guide explains more in the Program basics chapter.

If you are more interested in reading source code, you can find the code for the examples in this guide in the openrndr-examples repository.

If you are interested in more advanced examples, we recommend checking out the demo programs in the orx repository; most orx modules have demos in their src/demo/kotlin folder.

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