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As far as I know, the fastest way to draw is to use scene.createRenderable combined with Image.setRows. That’s what I use in Space Rocks 3D.

Here’s an older discussion about the topic: Is it possible to write directly to screen (pixels) on the Arcade?

scene.createRenderable takes a function as its second argument, that function gets called each time the screen content is refreshed on updates. The called function gets an Image as its first argument which is a reference to the screen buffer, you can modify that image to draw directly onto the screen.

The image.getRows and image.setRows methods copy pixels from the screen into a byte buffer and back.

Something like this (untested):

const buf = Buffer.create(120)
const zLayer = 0
scene.createRenderable(zLayer, (target: Image, camera: scene.Camera) => {
  for (let x = 0; x < 160; +=x) {
    // Read the current screen content for modification
    image.getRows(x, buf)
    // Now "buf" contains a color value for the current pixel row 
    // (it's actually a vertical column onscreen) where it can be modified.
    buf[12] = 15
    // Write the modified pixels back to the screen.
    image.setRows(x, buf)
  }
})
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