Refactor rewind functionality with circular buffer, update BufferedImageData handling in DisplayView, enhance ConsoleView rendering updates, and integrate SnakeCode data.

build.gradle.kts

@@ -67,7 +67,7 @@ kotlin {
     }
     val jsMain by getting {
       dependencies {
-        implementation("nl.astraeus:kotlin-komponent:1.2.5")
+        implementation("nl.astraeus:kotlin-komponent:1.2.8")
       }
     }
     val jsTest by getting

src/commonMain/kotlin/mtmc/asm/instructions/Instruction.kt

@@ -57,7 +57,7 @@ abstract class Instruction(
       if (ls != null) {
         return ls
       }
-      val jumpReg = JumpInstruction.disassemble(instruction)
+      val jumpReg = JumpRegisterInstruction.disassemble(instruction)
       if (jumpReg != null) {
         return jumpReg
       }
@@ -65,7 +65,7 @@ abstract class Instruction(
       if (jump != null) {
         return jump
       }
-      return "<unknown>"
+      return ""
     }
   }
 }

src/commonMain/kotlin/mtmc/asm/instructions/JumpRegisterInstruction.kt

@@ -26,10 +26,16 @@ class JumpRegisterInstruction(
 
   companion object {
     fun disassemble(instruction: Short): String? {
-      if (BinaryUtils.getBits(16, 5, instruction).toInt() == 9) {
+      if (BinaryUtils.getBits(16, 4, instruction).toInt() == 9) {
         val reg = BinaryUtils.getBits(4, 4, instruction)
-        val sb = StringBuilder("jr")
-        sb.append(fromInteger(reg.toInt()))
+        if (reg.toInt() == 11) {
+          return "ret"
+        } else {
+          val sb = StringBuilder("jr")
+          sb.append(" ")
+          sb.append(fromInteger(reg.toInt()))
+          return sb.toString()
+        }
       }
       return null
     }

src/commonMain/kotlin/mtmc/emulator/BufferedImage.kt

@@ -2,6 +2,8 @@ package mtmc.emulator
 
 expect fun createBufferedImage(width: Int, height: Int): BufferedImage
 
+expect fun createCanvasImage(width: Int, height: Int): BufferedImage
+
 interface BufferedImage {
   val width: Int
   val height: Int

src/commonMain/kotlin/mtmc/emulator/MTMCDisplay.kt

@@ -3,7 +3,7 @@ package mtmc.emulator
 import kotlin.math.min
 
 class MTMCDisplay(private val computer: MonTanaMiniComputer) {
-  private val buffer: BufferedImage? = null
+  val buffer: BufferedImage = createCanvasImage(COLS, ROWS)
   private var currentColor: DisplayColor? = null
   private var graphics: Array<BufferedImage> = arrayOf()
   private var byteArray: ByteArray = ByteArray(0)
@@ -107,11 +107,11 @@ class MTMCDisplay(private val computer: MonTanaMiniComputer) {
   }
 
   fun setPixel(col: Int, row: Int, color: DisplayColor) {
-    buffer?.setRGB(col, row, color.intVal)
+    buffer.setRGB(col, row, color.intVal)
   }
 
   fun getPixel(col: Int, row: Int): Short {
-    val rgb = buffer?.getRGB(col, row) ?: 0
+    val rgb = buffer.getRGB(col, row)
     return DisplayColor.indexFromInt(rgb)
   }
 
@@ -123,10 +123,11 @@ class MTMCDisplay(private val computer: MonTanaMiniComputer) {
   }
 
   fun drawRectangle(startCol: Short, startRow: Short, width: Short, height: Short) {
-//    val graphics = buffer.getGraphics()
-//    graphics.setColor(currentColor!!.javaColor)
-//    graphics.fillRect(startCol.toInt(), startRow.toInt(), width.toInt(), height.toInt())
-//    graphics.dispose()
+    for (x in startCol..<startCol + width) {
+      for (y in startRow..<startRow + height) {
+        setPixel(x, y, currentColor!!)
+      }
+    }
   }
 
   fun drawImage(image: Int, x: Int, y: Int) {

src/commonMain/kotlin/mtmc/emulator/MonTanaMiniComputer.kt

@@ -31,7 +31,9 @@ class MonTanaMiniComputer {
   var display: MTMCDisplay = MTMCDisplay(this)
   var clock: MTMCClock = MTMCClock(this)
   var fileSystem: FileSystem = FileSystem(this)
-  var rewindSteps = mutableListOf<RewindStep>()
+
+  var rewindSteps = Array<RewindStep?>(MAX_REWIND_STEPS) { null }
+  var rewindIndex = -1
 
   // listeners
   private val observers = mutableListOf<MTMCObserver>()
@@ -46,12 +48,12 @@ class MonTanaMiniComputer {
     registerFile = ShortArray(Register.entries.size)
     memory = ByteArray(MEMORY_SIZE)
     breakpoints = ByteArray(MEMORY_SIZE)
-    rewindSteps.clear()
+    rewindIndex = -1
     setRegisterValue(
       Register.SP,
       MEMORY_SIZE.toShort().toInt()
     ) // default the stack pointer to the top of memory
-    rewindSteps.clear()
+    rewindIndex = -1
     observers.forEach { obj ->
       obj.computerReset()
     }
@@ -134,7 +136,8 @@ class MonTanaMiniComputer {
   fun fetchAndExecute() {
     currentRewindStep = RewindStep()
     currentRewindStep?.let {
-      rewindSteps.add(0, it)
+      rewindIndex = (rewindIndex + 1) % rewindSteps.size
+      rewindSteps.set(rewindIndex, it)
     }
     fetchCurrentInstruction()
     val instruction = getRegisterValue(Register.IR)
@@ -795,11 +798,8 @@ class MonTanaMiniComputer {
   }
 
   private fun addRewindStep(runnable: Runnable?) {
-    if (currentRewindStep != null && rewindSteps != null) {
+    if (currentRewindStep != null) {
       currentRewindStep!!.addSubStep(runnable)
-      if (rewindSteps.size > MAX_REWIND_STEPS) {
-        rewindSteps.removeLast()
-      }
     }
   }
 
@@ -954,12 +954,15 @@ class MonTanaMiniComputer {
   }
 
   fun rewind() {
-    val latestRewindStep = rewindSteps.removeFirst()
-    latestRewindStep.rewind()
+    if (rewindIndex >= 0) {
+      val latestRewindStep = rewindSteps[rewindIndex]
+      rewindIndex--
+      latestRewindStep?.rewind()
+    }
   }
 
   val isBackAvailable: Boolean
-    get() = !rewindSteps!!.isEmpty()
+    get() = rewindIndex >= 0
 
   enum class ComputerStatus {
     READY,

src/commonMain/kotlin/mtmc/emulator/RewindStep.kt

@@ -3,7 +3,7 @@ package mtmc.emulator
 import mtmc.util.Runnable
 
 class RewindStep {
-  var subSteps: MutableList<Runnable?> = ArrayList<Runnable?>()
+  var subSteps: MutableList<Runnable?> = mutableListOf()
 
   fun rewind() {
     subSteps.reversed().forEach({ obj: Runnable? -> obj!!.invoke() })

src/jsMain/kotlin/mtmc/emulator/BufferedImage.js.kt

@@ -1,5 +1,12 @@
 package mtmc.emulator
 
+import kotlinx.browser.document
+import org.khronos.webgl.get
+import org.khronos.webgl.set
+import org.w3c.dom.CanvasRenderingContext2D
+import org.w3c.dom.HTMLCanvasElement
+import org.w3c.dom.ImageData
+
 actual fun createBufferedImage(
   width: Int,
   height: Int
@@ -25,10 +32,44 @@ class BufferedImageImpl(
     check(x in 0 until width && y in 0 until height)
 
     val offset = (x + y * width) * 4
-    display[offset + 0] = intVal.toByte()
+    display[offset + 0] = (intVal shr 16).toByte()
     display[offset + 1] = (intVal shr 8).toByte()
-    display[offset + 2] = (intVal shr 16).toByte()
+    display[offset + 2] = intVal.toByte()
     display[offset + 3] = 255.toByte()
   }
 }
 
+class BufferedImageData(
+  val imageData: ImageData,
+) : BufferedImage {
+  override val width: Int = imageData.width
+  override val height: Int = imageData.height
+
+  override fun getRGB(x: Int, y: Int): Int {
+    check(x in 0 until width && y in 0 until height)
+
+    val offset = (x * 4 + y * width * 4)
+    val display = imageData.data
+    return (display[offset + 0].toInt() and 0xff) shl 16 +
+        (display[offset + 1].toInt() and 0xff) shl 8 +
+        (display[offset + 2].toInt() and 0xff)
+  }
+
+  override fun setRGB(x: Int, y: Int, intVal: Int) {
+    check(x in 0 until width && y in 0 until height)
+
+    val offset = (x * 4 + y * width * 4)
+    val display = imageData.data
+    display[offset + 0] = ((intVal shr 16) and 0xff).toShort().asDynamic()
+    display[offset + 1] = ((intVal shr 8) and 0xff).toShort().asDynamic()
+    display[offset + 2] = (intVal and 0xff).toShort().asDynamic()
+    display[offset + 3] = 255.toShort().asDynamic()
+  }
+}
+
+val canvas = document.createElement("canvas") as HTMLCanvasElement
+val ctx = canvas.getContext("2d") as CanvasRenderingContext2D
+
+actual fun createCanvasImage(width: Int, height: Int): BufferedImage {
+  return BufferedImageData(ctx.createImageData(width.toDouble(), height.toDouble()));
+}

src/jsMain/kotlin/mtmc/util/PlatformSpecific.js.kt

@@ -1,6 +1,7 @@
 package mtmc.util
 
 import kotlinx.browser.window
+import mtmc.display
 import mtmc.mainView
 import kotlin.js.Date
 
@@ -11,8 +12,9 @@ actual fun requestAnimationFrame(action: (Double) -> Unit) {
   window.requestAnimationFrame {
     action(it)
 
-    mainView.registerView.requestUpdate()
+    display.requestUpdate()
     if (currentTimeMillis() - lastMemoryUpdate > 100) {
+      mainView.registerView.requestUpdate()
       mainView.memoryView.requestUpdate()
       lastMemoryUpdate = currentTimeMillis()
     }

src/jsMain/kotlin/mtmc/view/ConsoleView.kt

@@ -6,6 +6,7 @@ import kotlinx.html.input
 import kotlinx.html.js.onClickFunction
 import kotlinx.html.js.onKeyUpFunction
 import kotlinx.html.span
+import mtmc.display
 import mtmc.emulator.MonTanaMiniComputer
 import mtmc.mainView
 import mtmc.os.shell.Shell
@@ -65,7 +66,10 @@ class ConsoleView(
     Shell.execCommand(input, computer)
 
     input = ""
-    mainView.requestUpdate()
+    mainView.registerView.requestUpdate()
+    mainView.memoryView.requestUpdate()
+    display.requestUpdate()
+    requestUpdate()
   }
 
 }

src/jsMain/kotlin/mtmc/view/DisplayView.kt

@@ -3,13 +3,13 @@ package mtmc.view
 import kotlinx.html.canvas
 import kotlinx.html.div
 import mtmc.display
+import mtmc.emulator.BufferedImageData
 import mtmc.emulator.MonTanaMiniComputer
 import nl.astraeus.komp.HtmlBuilder
 import nl.astraeus.komp.Komponent
 import nl.astraeus.komp.currentElement
 import org.w3c.dom.CanvasRenderingContext2D
 import org.w3c.dom.HTMLCanvasElement
-import org.w3c.dom.ImageData
 
 class DiplayControlView(
   val computer: MonTanaMiniComputer
@@ -26,7 +26,6 @@ class DisplayView(
   val computer: MonTanaMiniComputer
 ) : Komponent() {
   var ctx: CanvasRenderingContext2D? = null
-  var imageData: ImageData? = null
 
   override fun HtmlBuilder.render() {
     canvas("display-canvas") {
@@ -37,16 +36,16 @@ class DisplayView(
 
       ctx = cv?.getContext("2d")?.unsafeCast<CanvasRenderingContext2D>()
 
-      ctx?.fillStyle = "#404040"
+      ctx?.fillStyle = "#400040"
       ctx?.fillRect(0.0, 0.0, 160.0, 144.0)
-      imageData = ctx?.getImageData(0.0, 0.0, 160.0, 144.0)
     }
   }
 
   override fun renderUpdate() {
     // move data to canvas
-    imageData?.let { id ->
-      ctx?.putImageData(id, 0.0, 0.0)
+    val buffer = computer.display.buffer
+    if (buffer is BufferedImageData) {
+      ctx?.putImageData(buffer.imageData, 0.0, 0.0)
     }
   }
 }

src/jvmMain/kotlin/mtmc/emulator/BufferedImage.jvm.kt

@@ -2,4 +2,8 @@ package mtmc.emulator
 
 actual fun createBufferedImage(width: Int, height: Int): BufferedImage {
   TODO("Not yet implemented")
+}
+
+actual fun createCanvasImage(width: Int, height: Int): BufferedImage {
+  TODO("Not yet implemented")
 }

src/jvmMain/kotlin/mtmc/util/PlatformSpecific.jvm.kt

@@ -5,4 +5,4 @@ actual fun requestAnimationFrame(action: (Double) -> Unit) {
   error("requestAnimationFrame is not supported on JVM")
 }
 
-actual fun immediateTimeout(action: (Double) -> Unit): Int {}
+actual fun immediateTimeout(action: (Double) -> Unit): Int = 0