orx/orx-olive/README.md

orx-olive

Live coding extension for OPENRNDR

usage

make sure that you add the following to your list of dependencies (next to orx-olive)

implementation "org.jetbrains.kotlin:kotlin-scripting-compiler-embeddable:1.3.31"

Then a simple live setup can created as follows:

import org.openrndr.Program
import org.openrndr.application
import org.openrndr.extra.olive.Olive

fun main() = application {
    configure {
        width = 768
        height = 576
    }
    program {
        extend(Olive<Program>())
    }
}

The extension will create a template script for you in src/main/kotlin/live.kts. You can edit this to see how the program updates automatically.

Shade style errors

Recent versions of orx-olive automatically set the org.openrndr.ignoreShadeStyleErrors property which makes OPENRNDR ignore errors in the shade style and return the default shader. To get this behaviour in older versions add -Dorg.openrndr.ignoreShadeStyleErrors=true to the JVM arguments.

Reloadable State

Along with the extension comes a mechanism that allows state to be reloaded from a store on script reload. This functionality is offered by the Reloadable class.

An example live.kts in which the reloadable state is used:

@file:Suppress("UNUSED_LAMBDA_EXPRESSION")
import org.openrndr.color.ColorRGBa
import org.openrndr.draw.*

{ program: PersistentProgram ->
    program.apply {
        val a = object : Reloadable() {
            var x : Double = 0.0
        } 
        a.reload()

        extend {
            // do something with a.x here
        }
    }
}

The Reloadable store can be cleared using the clearReloadables function.

Reloadable GPU resources

To store GPU resources or objects that use GPU resources (a.o. ColorBuffer, VertexBuffer, Shader, BufferTexture) in a Reloadable object one uses OPENRNDR's persistent {} builder function.

@file:Suppress("UNUSED_LAMBDA_EXPRESSION")
import org.openrndr.color.ColorRGBa
import org.openrndr.draw.*

{ program: PersistentProgram ->
    program.apply {
        val a = object : Reloadable() {
            var image = persistent { loadImage("data/images/pm5544.png" ) }
        }
        a.reload()

        extend {
            drawer.image(a.image)
        }
    }
}

Keep in mind that Reloadable should only be used for singleton classes.

Persistent Data

Sometimes you want to keep parts of your application persistent. In the following example we show how you can prepare the host program to contain a persistent camera device.

import org.openrndr.Program
import org.openrndr.application

class PersistentProgram: Program() {
    lateinit var camera: FFMPEGVideoPlayer
}

fun main() = application{
    program(PersistentProgram()) {
        camera = FFMPEGVideoPlayer.fromDevice()
        camera.start()

        extend(Olive<PersistentProgram>()) {
            script = "src/main/PersistentCamera.Kt"
        }
    }
}

The live script src/main/PersistentCamera.kts then looks like this:

@file:Suppress("UNUSED_LAMBDA_EXPRESSION")
import org.openrndr.color.ColorRGBa
import org.openrndr.draw.*

{ program: PersistentProgram ->
    program.apply {
        extend {
            camera.next()
            drawer.drawStyle.colorMatrix = tint(ColorRGBa.GREEN) * grayscale(0.0, 0.0, 1.0)
            camera.draw(drawer)
        }
    }
}

Demos

DemoOlive01

source code

DemoOliveScriptless01

source code