samples: add software 3D renderer in Kotlin

samples/kotlin/build.gradle.kts

@@ -15,7 +15,7 @@
  */
 
 plugins {
-    kotlin("jvm") version "1.8.0"
+    kotlin("multiplatform") version "1.9.20"
     war
     id("org.teavm")
 }
@@ -28,3 +28,7 @@ teavm.js {
     addedToWebApp = true
     mainClass = "org.teavm.samples.kotlin.HelloKt"
 }
+
+kotlin {
+    jvm()
+}

samples/settings.gradle.kts

@@ -59,6 +59,7 @@ include("pi")
 include("kotlin")
 include("scala")
 include("web-apis")
+include("software3d")
 
 gradle.allprojects {
     apply<WarPlugin>()

samples/software3d/build.gradle.kts

@@ -0,0 +1,67 @@
+import org.teavm.gradle.api.OptimizationLevel
+import org.teavm.gradle.tasks.TeaVMTask
+
+/*
+ *  Copyright 2023 Alexey Andreev.
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *       http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+
+plugins {
+    kotlin("multiplatform") version "1.9.20"
+    war
+    id("org.teavm")
+}
+
+tasks.withType<org.jetbrains.kotlin.gradle.tasks.KotlinCompile>().configureEach {
+    kotlinOptions {
+        jvmTarget = "11"
+    }
+}
+
+teavm.js {
+    addedToWebApp = true
+    mainClass = "org.teavm.samples.software3d.teavm.MainKt"
+}
+
+teavm.wasm {
+    addedToWebApp = true
+    mainClass = "org.teavm.samples.software3d.teavm.WasmWorkerKt"
+    optimization = OptimizationLevel.AGGRESSIVE
+    minHeapSize = 4
+}
+
+kotlin {
+    js {
+        browser {
+
+        }
+        binaries.executable()
+    }
+    jvm()
+    sourceSets.jvmMain.dependencies {
+        implementation(teavm.libs.jsoApis)
+    }
+}
+
+tasks.withType<TeaVMTask> {
+    classpath.from(kotlin.jvm().compilations["main"].output.classesDirs)
+}
+
+tasks.war {
+    dependsOn(tasks.named("jsBrowserDistribution"))
+    with(copySpec {
+        from(kotlin.js().binaries.executable().map { it.distribution.outputDirectory })
+        into("kjs")
+    })
+}

samples/software3d/src/commonMain/kotlin/org/teavm/samples/software3d/geometry/Face.kt

@@ -0,0 +1,21 @@
+/*
+ *  Copyright 2023 Alexey Andreev.
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *       http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+
+package org.teavm.samples.software3d.geometry
+
+import org.teavm.samples.software3d.scene.Vertex
+
+class Face(val a: Vertex, val b: Vertex, val c: Vertex)

samples/software3d/src/commonMain/kotlin/org/teavm/samples/software3d/geometry/GeneralMatrix.kt

@@ -0,0 +1,64 @@
+/*
+ *  Copyright 2023 Alexey Andreev.
+ *
+ *  Licensed under the Apache License, Version 2.0 (the "License");
+ *  you may not use this file except in compliance with the License.
+ *  You may obtain a copy of the License at
+ *
+ *       http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *  Unless required by applicable law or agreed to in writing, software
+ *  distributed under the License is distributed on an "AS IS" BASIS,
+ *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  See the License for the specific language governing permissions and
+ *  limitations under the License.
+ */
+
+package org.teavm.samples.software3d.geometry
+
+interface GeneralMatrix {
+    val size: Int
+
+    fun get(row: Int, col: Int): Float
+
+    fun determinant(): Float {
+        return if (size == 2) {
+            get(0, 0) * get(1, 1) - get(1, 0) * get(0, 1)
+        } else {
+            (0 until size)
+                    .map { j ->
+                        val r = get(0, j) * exclude(0, j).determinant()
+                        if (j % 2 == 0) r else -r
+                    }
+                    .sum()
+        }
+    }
+
+    fun exclude(excludeRow: Int, excludeCol: Int): GeneralMatrix {
+        val orig = this
+        return object : GeneralMatrix {
+            override val size: Int
+                get() = orig.size - 1
+
+            override fun get(row: Int, col: Int): Float {
+                return orig.get(if (row < excludeRow) row else row + 1, if (col < excludeCol) col else col + 1)
+            }
+        }
+    }
+
+    fun asString(): String {
+        val cells = (0 until size).map { j ->
+            (0 until size).map { i ->
+                get(i, j).toString()
+            }
+        }
+        val lengths = cells.map { column -> column.maxOf { it.length } }
+        val padCells = (cells zip lengths).map { (column, length) ->
+            column.map { it + " ".repeat(length - it.length) }
+        }
+
+        return (0 until size).joinToString("\n") { i ->
+            (0 until size).joinToString(" ") { j -> padCells[j][i] }
+        }
+    }
+}