1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
|
import kotlinx.browser.document
import org.w3c.dom.CanvasRenderingContext2D
import org.w3c.dom.HTMLCanvasElement
class Renderer(val viewportWidth: Int, val viewportHeight: Int, private val outputScale: Int) {
private val canvas = (document.getElementById("render-output") as HTMLCanvasElement)
.apply {
width = viewportWidth * outputScale
height = viewportHeight * outputScale
}
private val context = (canvas.getContext("2d") as CanvasRenderingContext2D)
.apply { scale(outputScale.toDouble(), outputScale.toDouble()) }
fun drawLine(startX: Double, startY: Double, endX: Double, endY: Double, cssColour: String = "#FF0000") {
context.strokeStyle = cssColour
context.lineWidth = 2.0
context.beginPath()
context.moveTo(startX, startY)
context.lineTo(endX, endY)
context.stroke()
}
fun drawLine(startX: Int, startY: Double, endX: Int, endY: Double, cssColour: String = "#FF0000") {
drawLine(startX.toDouble(), startY, endX.toDouble(), endY, cssColour)
}
fun drawLine(startX: Int, startY: Double, endX: Int, endY: Int, cssColour: String = "#FF0000") {
drawLine(startX.toDouble(), startY, endX.toDouble(), endY.toDouble(), cssColour)
}
fun clear() {
context.clearRect(0.0, 0.0, viewportWidth.toDouble(), viewportHeight.toDouble())
}
}
|