Is there a way to perform vector draws on low level, just by executing functions? The only way to draw I currently know is to create an object for every visible vector primitive I have and manage it. For example, I can do

val c = circle()

and then when I don't need it I must do

c.removeFromParent()

to avoid memory leaks. Can I just draw a circle without creating an object? Like in Canvas2D Web API, for example?

val c = graphics { circle(...) }

Oops, it seems there is still some kind of leak... I see that FPS gradually becomes lower and lower. What am I doing wrong?

suspend fun main() = Korge {
    Logger.defaultLevel = Logger.Level.DEBUG

    val rect = Rectangle(0, 10, 20, 20)
    val g = graphics()

    addHrUpdater { delta ->
        log.debug { "FPS: ${ (1000 / delta.millisecondsDouble).roundToInt() }" }

        ++rect.x
        if (rect.x > 100) {
            rect.x = 0.0
        }

        g.apply {
            fill(Colors.BLACK) {
                rect(0.0, 0.0, this@Korge.width, this@Korge.height)
            }

            fill(Colors.YELLOW) {
                with(rect) { rect(x, y, width, height) }
            }
        }
    }
}

misses a

clear

inside g.apply

Great, thank you! It now works. AFAIR, LibGDX is more effective in terms of low-level graphics calls. The same code for painting there:

Gdx.gl.glClearColor(0, 0, 0, 1)
Gdx.gl.glClear(GL20.GL_COLOR_BUFFER_BIT)

shapeRenderer.begin(ShapeType.Filled)
shapeRenderer.setColor(255 / 255.0f, 255 / 255.0f, 0 / 255.0f, 1f)
with(rect) { shapeRenderer.rect(x, y, width, height) }
shapeRenderer.end()

There I could easily draw many primitives at 144 FPS. I think there was no hacks with software rasterizing... Is it possible to optimize this in KorGE? Of course, there are many places where you can prealocate Views to draw, but also there are cases when you don't know which and how many primitives you need to draw, and it seems KorGE can't handle these cases effectively now.

just a rect?