September 2017 Update

2017-09-23 10:01:46 +02:00 · 2017-09-23 10:01:46 +02:00 · ba8067c3b7
commit ba8067c3b7
parent bba7bfd280
14570 changed files with 153136 additions and 63871 deletions
--- a/Task/Xiaolin-Wus-line-algorithm/Kotlin/xiaolin-wus-line-algorithm.kotlin
+++ b/Task/Xiaolin-Wus-line-algorithm/Kotlin/xiaolin-wus-line-algorithm.kotlin
@ -0,0 +1,101 @@
+// version 1.1.2
+
+import java.awt.*
+import javax.swing.*
+
+class XiaolinWu: JPanel() {
+    init {
+        preferredSize = Dimension(640, 640)
+        background = Color.white
+    }
+
+    private fun plot(g: Graphics2D, x: Double, y: Double, c: Double) {
+        g.color = Color(0f, 0f, 0f, c.toFloat())
+        g.fillOval(x.toInt(), y.toInt(), 2, 2)
+    }
+
+    private fun ipart(x: Double) = x.toInt()
+
+    private fun fpart(x: Double) = x - Math.floor(x)
+
+    private fun rfpart(x: Double) = 1.0 - fpart(x)
+
+    private fun drawLine(g: Graphics2D, x0: Double, y0: Double, x1: Double, y1: Double) {
+        val steep = Math.abs(y1 - y0) > Math.abs(x1 - x0)
+        if (steep) drawLine(g, y0, x0, y1, x1)
+        if (x0 > x1) drawLine(g, x1, y1, x0, y0)
+
+        val dx = x1 - x0
+        val dy = y1 - y0
+        val gradient = dy / dx
+
+        // handle first endpoint
+        var xend = Math.round(x0).toDouble()
+        var yend = y0 + gradient * (xend - x0)
+        var xgap = rfpart(x0 + 0.5)
+        val xpxl1 = xend  // this will be used in the main loop
+        val ypxl1 = ipart(yend).toDouble()
+
+        if (steep) {
+            plot(g, ypxl1, xpxl1, rfpart(yend) * xgap)
+            plot(g, ypxl1 + 1.0, xpxl1, fpart(yend) * xgap)
+        }
+        else {
+            plot(g, xpxl1, ypxl1, rfpart(yend) * xgap)
+            plot(g, xpxl1, ypxl1 + 1.0, fpart(yend) * xgap)
+        }
+
+        // first y-intersection for the main loop
+        var intery = yend + gradient
+
+        // handle second endpoint
+        xend = Math.round(x1).toDouble()
+        yend = y1 + gradient * (xend - x1)
+        xgap = fpart(x1 + 0.5)
+        val xpxl2 = xend  // this will be used in the main loop
+        val ypxl2 = ipart(yend).toDouble()
+
+        if (steep) {
+            plot(g, ypxl2, xpxl2, rfpart(yend) * xgap)
+            plot(g, ypxl2 + 1.0, xpxl2, fpart(yend) * xgap)
+        }
+        else {
+            plot(g, xpxl2, ypxl2, rfpart(yend) * xgap)
+            plot(g, xpxl2, ypxl2 + 1.0, fpart(yend) * xgap)
+        }
+
+        // main loop
+        var x = xpxl1 + 1.0
+        while (x <=  xpxl2 - 1) {
+            if (steep) {
+                plot(g, ipart(intery).toDouble(), x, rfpart(intery))
+                plot(g, ipart(intery).toDouble() + 1.0, x, fpart(intery))
+            }
+            else {
+                plot(g, x, ipart(intery).toDouble(), rfpart(intery))
+                plot(g, x, ipart(intery).toDouble() + 1.0, fpart(intery))
+            }
+            intery += gradient
+            x++
+        }
+    }
+
+    override protected fun paintComponent(gg: Graphics) {
+        super.paintComponent(gg)
+        val g = gg as Graphics2D
+        drawLine(g, 550.0, 170.0, 50.0, 435.0)
+    }
+}
+
+fun main(args: Array<String>) {
+    SwingUtilities.invokeLater {
+        val f = JFrame()
+        f.defaultCloseOperation = JFrame.EXIT_ON_CLOSE
+        f.title = "Xiaolin Wu's line algorithm"
+        f.isResizable = false
+        f.add(XiaolinWu(), BorderLayout.CENTER)
+        f.pack()
+        f.setLocationRelativeTo(null)
+        f.isVisible = true
+    }
+}