JavaFX Reset Graphics Context

Question

I'm working on a video game that redraws every 1/60 of a second using Kotlin and TornadoFX/JavaFX. Currently, my program redraws by setting the background to white and drawing over it. However, I would prefer something that is a bit cleaner. This is how I'm drawing it currently:

private fun drawShapes(gc: GraphicsContext) {
    gc.fill = c(255, 255, 255)
    gc.fillRect(0.0, 0.0, 700.0, 700.0) //Game is 700x700
    gc.fill = c(94, 132, 233)
    walls.forEach { gc.fillRect(it.x.toDouble(), it.y.toDouble(), it.w.toDouble(), it.h.toDouble()) }
    gc.fill = c(255, 239, 20)
    coins.filter { !it.collected }.forEach { gc.fillRect(it.x.toDouble(), it.y.toDouble(), it.w.toDouble(), it.h.toDouble()) }
    //Cut off here because following is more of same
}
fixedRateTimer(period = 16, initialDelay = 500) { drawShapes(graphicsContext2D) }

Is there any way to simply wipe it clean instead of layering a lot on top of each other? I've tried searching the internet for it, but I couldn't find anything.

You should [profile](http://stackoverflow.com/q/2064427/230513) to see what's "causing lag issues." — trashgod, Dec 08 '17 at 01:52
@trashgod I'm not really sure how to use the programs you linked. Also, it's mainly just preferable to me. I'll remove the misleading portion. — fin444, Dec 08 '17 at 02:53
Two approaches are contrasted [here](https://stackoverflow.com/a/44141878/230513). — trashgod, Dec 08 '17 at 12:30

score 0 · Accepted Answer · answered Jan 05 '18 at 19:45

0

Turns out there isn't really a way to do this. However, blanking out the canvas and drawing it again didn't cause any issues. The issues were being caused another part of the program.

answered Jan 05 '18 at 19:45

fin444

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score 0 · Answer 2 · answered Jan 06 '18 at 13:54

If the background of your game is consistently white then I would consider inserting a pane behind the canvas that has a white background color. You can still draw your foreground images just as you currently are and then to clear the canvas between frames use clearRect.

gc.clearRect(0.0, 0.0, 700.0, 700.0);

JavaFX Reset Graphics Context

2 Answers2