feat: Phase 2 Bausystem (Raycast, platzieren/abreißen, Block-Auswahl, Fadenkreuz) + LWJGL arm64-Fix + Gitea CI

- LWJGL natives fuer macOS aarch64 (arm64) ergaenzt
- GL.createCapabilities() nach Kontext-Bindung (LWJGL 3 Pflicht)
- VoxelWorld.raycast (DDA), public set()
- PlayerController.overlapsCell (verhindert Platzieren in Spieler)
- Game: Linksklick abbauen, Rechtsklick platzieren, 1-6 Auswahl, Mesh-Rebuild
- Crosshair-Overlay (NDC Screen-Space)
- .gitea/workflows/build.yml (build-on-push, ubuntu-latest)

.gitea/workflows/build.yml

@@ -0,0 +1,21 @@
+name: build
+on:
+  push:
+    branches: [main, dev]
+  pull_request:
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+      - name: Set up JDK 21
+        uses: actions/setup-java@v4
+        with:
+          distribution: temurin
+          java-version: '21'
+      - name: Make gradlew executable
+        run: chmod +x gradlew
+      - name: Build (compile + jar)
+        run: ./gradlew build --no-daemon

README.md

@@ -19,10 +19,13 @@ Hintergrund weiter — auch wenn es geschlossen ist.
 ./gradlew build      # kompiliert + erstellt Jar
 ```
 
-## Steuerung (Phase 1)
+## Steuerung (Phase 1 + 2)
 - **W/A/S/D** — Laufen
 - **Maus** — Umsehen (Pointer ist gefangen)
 - **Leertaste** — Springen
+- **Linksklick** — Block abbauen (vor der Kamera)
+- **Rechtsklick** — Block platzieren (leere Zelle davor)
+- **1–6** — Block-Auswahl: 1=Gras, 2=Erde, 3=Stein, 4=Holz, 5=Blaetter, 6=Wasser
 - **Esc** — Fenster schließen (beendet)
 
 ## Projektstruktur

build.gradle

@@ -22,10 +22,14 @@ dependencies {
     implementation 'org.lwjgl:lwjgl-glfw:3.3.3'
     implementation 'org.lwjgl:lwjgl-opengl:3.3.3'
 
-    // Native Libs für macOS (universal: arm64 + x86_64)
+    // Native Libs für macOS — BEIDE Architekturen (x64 + arm64/Apple Silicon).
+    // LWJGL klassifiziert 'natives-macos' als x64; auf aarch64 JVM braucht es zwingend natives-macos-arm64.
     runtimeOnly 'org.lwjgl:lwjgl:3.3.3:natives-macos'
+    runtimeOnly 'org.lwjgl:lwjgl:3.3.3:natives-macos-arm64'
     runtimeOnly 'org.lwjgl:lwjgl-glfw:3.3.3:natives-macos'
+    runtimeOnly 'org.lwjgl:lwjgl-glfw:3.3.3:natives-macos-arm64'
     runtimeOnly 'org.lwjgl:lwjgl-opengl:3.3.3:natives-macos'
+    runtimeOnly 'org.lwjgl:lwjgl-opengl:3.3.3:natives-macos-arm64'
 }
 
 application {

src/main/java/de/jfritzsche/homegarden/core/Game.java

@@ -2,17 +2,23 @@ package de.jfritzsche.homegarden.core;
 
 import static org.lwjgl.glfw.GLFW.*;
 import static org.lwjgl.opengl.GL11.*;
+import static org.lwjgl.opengl.GL.createCapabilities;
 
 import de.jfritzsche.homegarden.gfx.Camera;
+import de.jfritzsche.homegarden.gfx.Crosshair;
 import de.jfritzsche.homegarden.gfx.Mesh;
 import de.jfritzsche.homegarden.gfx.Shader;
 import de.jfritzsche.homegarden.math.Mat4;
+import de.jfritzsche.homegarden.math.Vec3;
 import de.jfritzsche.homegarden.player.PlayerController;
+import de.jfritzsche.homegarden.world.Block;
 import de.jfritzsche.homegarden.world.VoxelWorld;
 
 /**
- * Spielschleife + Rendering. Phase 1: statische Voxelwelt + FP-Laufen.
- * Spawn: Mitte der Welt, Fuesse auf der Grasoberflaeche.
+ * Spielschleife + Rendering.
+ * Phase 1: statische Voxelwelt + FP-Laufen.
+ * Phase 2: Bausystem — Raycast, Linksklick abbauen, Rechtsklick platzieren,
+ *          Block-Auswahl 1..6, Mesh-Rebuild, Fadenkreuz.
  */
 public final class Game {
     private final Window window = new Window();
@@ -23,17 +29,23 @@ public final class Game {
 
     private Shader shader;
     private Mesh worldMesh;
+    private Crosshair crosshair;
+
+    private int selectedBlock = Block.STONE;
+    private final int[] placeable = {Block.GRASS, Block.DIRT, Block.STONE, Block.WOOD, Block.LEAVES, Block.WATER};
 
     private static final double SENS = 0.0022;
     private static final float FOV = (float) Math.toRadians(70f);
 
     public void run() {
         window.create(1280, 720, "HomeGarden");
+        createCapabilities(); // LWJGL 3: laedt native GL-Funktionen fuer den Kontext
         glEnable(GL_DEPTH_TEST);
         glDisable(GL_CULL_FACE); // einfache Wuerfelflaechen brauchen kein Culling
 
         shader = new Shader(VS, FS);
         worldMesh = world.buildMesh();
+        crosshair = new Crosshair();
 
         player.update(0f, camera, new boolean[5], world); // Kamera an Spawn syncen
 
@@ -45,6 +57,7 @@ public final class Game {
 
             applyMouseLook();
             player.update(dt, camera, window.keysForMovement(), world);
+            handleBuild();
             render();
 
             window.pollEvents();
@@ -63,6 +76,53 @@ public final class Game {
         if (camera.pitch < -lim) camera.pitch = -lim;
     }
 
+    private void handleBuild() {
+        int digit = window.consumeDigit();
+        if (digit >= 1 && digit <= placeable.length) {
+            selectedBlock = placeable[digit - 1];
+            System.out.println("[HomeGarden] Block ausgewaehlt: " + blockName(selectedBlock));
+        }
+
+        boolean[] click = window.consumeClicks();
+        if (!click[0] && !click[1]) return;
+
+        int[] hit = new int[3], prev = new int[3];
+        Vec3 o = new Vec3(camera.position.x, camera.position.y, camera.position.z);
+        Vec3 d = camera.forward();
+        if (!world.raycast(o, d, 6f, hit, prev)) return; // ins Leere geschaut
+
+        if (click[0]) { // Linksklick: abbauen
+            world.set(hit[0], hit[1], hit[2], Block.AIR);
+            rebuildMesh();
+        } else { // Rechtsklick: platzieren (in der leeren Zelle vor dem Treffer)
+            int bx = prev[0], by = prev[1], bz = prev[2];
+            if (!world.isSolid(bx, by, bz)
+                && !player.overlapsCell(bx, by, bz)
+                && bx >= 0 && by >= 0 && bz >= 0
+                && bx < world.sx && by < world.sy && bz < world.sz) {
+                world.set(bx, by, bz, selectedBlock);
+                rebuildMesh();
+            }
+        }
+    }
+
+    private void rebuildMesh() {
+        worldMesh.dispose();
+        worldMesh = world.buildMesh();
+    }
+
+    private String blockName(int id) {
+        switch (id) {
+            case Block.GRASS:  return "Gras";
+            case Block.DIRT:   return "Erde";
+            case Block.STONE:  return "Stein";
+            case Block.WOOD:   return "Holz";
+            case Block.LEAVES: return "Blaetter";
+            case Block.WATER:  return "Wasser";
+            default:           return "?";
+        }
+    }
+
     private void render() {
         glClearColor(0.53f, 0.81f, 0.98f, 1f); // Himmelblau
         glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
@@ -73,10 +133,16 @@ public final class Game {
         shader.setMat4("u_proj", proj.toBuffer());
         shader.setMat4("u_view", view.toBuffer());
         worldMesh.draw();
+
+        // Fadenkreuz: ohne Tiefentest, immer oben
+        glDisable(GL_DEPTH_TEST);
+        crosshair.draw();
+        glEnable(GL_DEPTH_TEST);
     }
 
     private void cleanup() {
         worldMesh.dispose();
+        crosshair.dispose();
         glfwTerminate();
     }
 

src/main/java/de/jfritzsche/homegarden/core/Window.java

@@ -7,7 +7,8 @@ import org.lwjgl.glfw.GLFWErrorCallback;
 
 /**
  * GLFW-Fenster + Input. Pointer ist gefangen (FP-Look).
- * Tastenstatus und Maus-Delta werden fuer den Game-Loop gepuffert.
+ * Tastenstatus, Maus-Delta, Klick-Events und ausgewaehlte Ziffer werden
+ * fuer den Game-Loop gepuffert.
  */
 public final class Window {
     private long handle;
@@ -17,6 +18,9 @@ public final class Window {
     private boolean firstMouse = true;
     private int width = 1280, height = 720;
 
+    private final boolean[] clicked = new boolean[2]; // [0]=links, [1]=rechts
+    private int pendingDigit = -1;
+
     public void create(int w, int h, String title) {
         GLFWErrorCallback.createPrint(System.err).set();
         if (!glfwInit()) throw new IllegalStateException("glfwInit failed");
@@ -42,6 +46,9 @@ public final class Window {
             if (key >= 0 && key < keys.length) {
                 keys[key] = (action == GLFW_PRESS || action == GLFW_REPEAT);
             }
+            if (key >= GLFW_KEY_1 && key <= GLFW_KEY_6 && action == GLFW_PRESS) {
+                pendingDigit = key - GLFW_KEY_1 + 1;
+            }
         });
 
         glfwSetCursorPosCallback(handle, (win, x, y) -> {
@@ -51,6 +58,12 @@ public final class Window {
             lastX = x; lastY = y;
         });
 
+        glfwSetMouseButtonCallback(handle, (win, button, action, mods) -> {
+            if (action != GLFW_PRESS) return;
+            if (button == GLFW_MOUSE_BUTTON_LEFT) clicked[0] = true;
+            else if (button == GLFW_MOUSE_BUTTON_RIGHT) clicked[1] = true;
+        });
+
         glfwSetFramebufferSizeCallback(handle, (win, ww, hh) -> {
             glViewport(0, 0, ww, hh);
             width = ww; height = hh;
@@ -75,4 +88,16 @@ public final class Window {
         out[0] = mouseDX; out[1] = mouseDY;
         mouseDX = 0; mouseDY = 0;
     }
+
+    /** Liefert Links/Rechts-Klick zurueck (edge-triggered, einmalig). */
+    public boolean[] consumeClicks() {
+        boolean[] r = new boolean[] {clicked[0], clicked[1]};
+        clicked[0] = false; clicked[1] = false;
+        return r;
+    }
+
+    /** Liefert zuletzt gedrueckte Ziffer 1..6 zurueck (oder -1). */
+    public int consumeDigit() {
+        int d = pendingDigit; pendingDigit = -1; return d;
+    }
 }

src/main/java/de/jfritzsche/homegarden/gfx/Crosshair.java

@@ -0,0 +1,76 @@
+package de.jfritzsche.homegarden.gfx;
+
+import static org.lwjgl.opengl.GL11.*;
+import static org.lwjgl.opengl.GL15.*;
+import static org.lwjgl.opengl.GL20.*;
+import static org.lwjgl.opengl.GL30.*;
+
+/** Fadenkreuz als Screen-Space-Overlay (NDC, kein Tiefentest). */
+public final class Crosshair {
+    private final int vao, vbo, program;
+
+    private static final String VS = """
+        #version 330 core
+        layout(location = 0) in vec2 aPos;
+        void main() { gl_Position = vec4(aPos, 0.0, 1.0); }
+        """;
+
+    private static final String FS = """
+        #version 330 core
+        out vec4 fragColor;
+        void main() { fragColor = vec4(0.95f, 0.95f, 0.95f, 1.0); }
+        """;
+
+    public Crosshair() {
+        float t = 0.004f, L = 0.012f; // dicke / laenge
+        float[] verts = {
+            -L, -t,  L, -t,  L, t,
+            -L, -t,  L,  t, -L, t,
+            -t, -L,  t, -L,  t, L,
+            -t, -L,  t,  L, -t, L,
+        };
+        program = glCreateProgram();
+        int vs = compile(GL_VERTEX_SHADER, VS);
+        int fs = compile(GL_FRAGMENT_SHADER, FS);
+        glAttachShader(program, vs);
+        glAttachShader(program, fs);
+        glLinkProgram(program);
+        if (glGetProgrami(program, GL_LINK_STATUS) == 0) {
+            throw new RuntimeException("Crosshair link failed: " + glGetProgramInfoLog(program));
+        }
+        glDeleteShader(vs);
+        glDeleteShader(fs);
+
+        vao = glGenVertexArrays();
+        glBindVertexArray(vao);
+        vbo = glGenBuffers();
+        glBindBuffer(GL_ARRAY_BUFFER, vbo);
+        glBufferData(GL_ARRAY_BUFFER, verts, GL_STATIC_DRAW);
+        glEnableVertexAttribArray(0);
+        glVertexAttribPointer(0, 2, GL_FLOAT, false, 0, 0);
+        glBindVertexArray(0);
+    }
+
+    private static int compile(int type, String src) {
+        int id = glCreateShader(type);
+        glShaderSource(id, src);
+        glCompileShader(id);
+        if (glGetShaderi(id, GL_COMPILE_STATUS) == 0) {
+            throw new RuntimeException("Crosshair shader failed: " + glGetShaderInfoLog(id));
+        }
+        return id;
+    }
+
+    public void draw() {
+        glUseProgram(program);
+        glBindVertexArray(vao);
+        glDrawArrays(GL_TRIANGLES, 0, 12);
+        glBindVertexArray(0);
+    }
+
+    public void dispose() {
+        glDeleteVertexArrays(vao);
+        glDeleteBuffers(vbo);
+        glDeleteProgram(program);
+    }
+}

src/main/java/de/jfritzsche/homegarden/player/PlayerController.java

@@ -85,4 +85,14 @@ public final class PlayerController {
     }
 
     public Vec3 position() { return pos; }
+
+    /** Prueft, ob die Spieler-AABB die Voxelzelle (bx,by,bz) ueberschneidet. */
+    public boolean overlapsCell(int bx, int by, int bz) {
+        float minX = pos.x - halfW, maxX = pos.x + halfW;
+        float minY = pos.y,         maxY = pos.y + height;
+        float minZ = pos.z - halfW, maxZ = pos.z + halfW;
+        return maxX > bx && minX < bx + 1
+            && maxY > by && minY < by + 1
+            && maxZ > bz && minZ < bz + 1;
+    }
 }

src/main/java/de/jfritzsche/homegarden/world/VoxelWorld.java

@@ -1,6 +1,7 @@
 package de.jfritzsche.homegarden.world;
 
 import de.jfritzsche.homegarden.gfx.Mesh;
+import de.jfritzsche.homegarden.math.Vec3;
 
 import java.util.ArrayList;
 import java.util.List;
@@ -49,7 +50,56 @@ public final class VoxelWorld {
         return get(x, y, z) != Block.AIR;
     }
 
-    private void set(int x, int y, int z, int id) {
+    /**
+     * Voxel-Raycast (Amanat/DDA). Start = Kamera, dir = normierte Blickrichtung.
+     * Liefert bei Treffer die getroffene Zelle in 'hit' und die Zelle davor in
+     * 'prev' (zum Platzieren). maxDist in Block-Einheiten.
+     */
+    public boolean raycast(Vec3 origin, Vec3 dir, float maxDist, int[] hit, int[] prev) {
+        int ix = (int) Math.floor(origin.x);
+        int iy = (int) Math.floor(origin.y);
+        int iz = (int) Math.floor(origin.z);
+
+        float stepX = dir.x > 0 ? 1 : (dir.x < 0 ? -1 : 0);
+        float stepY = dir.y > 0 ? 1 : (dir.y < 0 ? -1 : 0);
+        float stepZ = dir.z > 0 ? 1 : (dir.z < 0 ? -1 : 0);
+
+        float tDeltaX = dir.x != 0 ? Math.abs(1f / dir.x) : Float.POSITIVE_INFINITY;
+        float tDeltaY = dir.y != 0 ? Math.abs(1f / dir.y) : Float.POSITIVE_INFINITY;
+        float tDeltaZ = dir.z != 0 ? Math.abs(1f / dir.z) : Float.POSITIVE_INFINITY;
+
+        float tMaxX = nextT(origin.x, ix, stepX, tDeltaX);
+        float tMaxY = nextT(origin.y, iy, stepY, tDeltaY);
+        float tMaxZ = nextT(origin.z, iz, stepZ, tDeltaZ);
+
+        int px = ix, py = iy, pz = iz;
+        float t = 0f;
+        while (t <= maxDist) {
+            if (isSolid(ix, iy, iz)) {
+                hit[0] = ix; hit[1] = iy; hit[2] = iz;
+                prev[0] = px; prev[1] = py; prev[2] = pz;
+                return true;
+            }
+            px = ix; py = iy; pz = iz;
+            if (tMaxX < tMaxY && tMaxX < tMaxZ) {
+                t = tMaxX; tMaxX += tDeltaX; ix += stepX;
+            } else if (tMaxY < tMaxZ) {
+                t = tMaxY; tMaxY += tDeltaY; iy += stepY;
+            } else {
+                t = tMaxZ; tMaxZ += tDeltaZ; iz += stepZ;
+            }
+        }
+        return false;
+    }
+
+    private static float nextT(float o, int i, float step, float tDelta) {
+        if (step > 0) return (i + 1 - o) * tDelta;
+        if (step < 0) return (o - i) * tDelta;
+        return Float.POSITIVE_INFINITY;
+    }
+
+    /** Setzt einen Block (oeffentlich — Bausystem/Platzieren). */
+    public void set(int x, int y, int z, int id) {
         if (x < 0 || y < 0 || z < 0 || x >= sx || y >= sy || z >= sz) return;
         blocks[idx(x, y, z)] = (byte) id;
     }