an actual planet

core/src/mindustry/graphics/PlanetRenderer.java

@@ -5,31 +5,47 @@ import arc.graphics.*;
 import arc.graphics.g2d.*;
 import arc.graphics.g3d.*;
 import arc.math.*;
+import arc.math.geom.*;
+import arc.struct.*;
 import arc.util.*;
+import arc.util.noise.*;
 
 public class PlanetRenderer{
-    private ImmediateRenderer3D rend = new ImmediateRenderer3D(true, true, 0);
+    private ImmediateRenderer3D rend = new ImmediateRenderer3D(500000, true, true, 0);
     private Camera3D cam = new Camera3D();
 
+    private ShortArray tmpIndices = new ShortArray();
+    private ShortArray indices = new ShortArray();
+    private Array<Vertex> vertices = new Array<>();
+
+    private Color[] colors = {Color.royal, Color.tan, Color.forest, Color.olive, Color.lightGray, Color.white};
+    private Simplex sim = new Simplex();
+
+    {
+        int div = 100;
+        generate(15, 15, 15, div, div);
+    }
+
     public void draw(){
         Draw.flush();
         Gl.clearColor(0, 0, 0, 1);
-        //Gl.clear(Gl.depthBufferBit | Gl.colorBufferBit);
-        Gl.lineWidth(40f);
+        Gl.clear(Gl.depthBufferBit | Gl.colorBufferBit);
+        Gl.enable(Gl.depthTest);
 
-        Tmp.v1.trns(Time.time() / 4f, 20f);
+        Tmp.v1.trns(Time.time(), 20f);
         cam.position.set(Tmp.v1.x, 0f, Tmp.v1.y);
         cam.resize(Core.graphics.getWidth(), Core.graphics.getHeight());
         cam.update();
         cam.lookAt(0, 0, 0);
         cam.update();
 
-        rend.begin(cam.combined(), Gl.points);
-        build(15, 15, 15, 60, 60);
+        rend.begin(cam.combined(), Gl.triangleStrip);
+        drawSphere();
         rend.end();
+        Gl.disable(Gl.depthTest);
     }
 
-    void build(float width, float height, float depth, int divisionsU, int divisionsV) {
+    void generate(float width, float height, float depth, int divisionsU, int divisionsV){
         float angleUFrom = 0, angleUTo = 360f, angleVFrom = 0, angleVTo = 180f;
         final float hw = width * 0.5f;
         final float hh = height * 0.5f;
@@ -45,21 +61,76 @@ public class PlanetRenderer{
         final int s = divisionsU + 3;
         int tempOffset = 0;
 
-        for (int iv = 0; iv <= divisionsV; iv++) {
+        tmpIndices.clear();
+        tmpIndices.ensureCapacity(divisionsU * 2);
+        tmpIndices.size = s;
+
+        vertices.clear();
+        indices.clear();
+
+        for(int iv = 0; iv <= divisionsV; iv++){
             angleV = avo + stepV * iv;
             v = vs * iv;
             final float t = Mathf.sin(angleV);
             final float h = Mathf.cos(angleV) * hh;
-            for (int iu = 0; iu <= divisionsU; iu++) {
+            for(int iu = 0; iu <= divisionsU; iu++){
                 angleU = auo + stepU * iu;
                 u = 1f - us * iu;
                 Tmp.v31.set(Mathf.cos(angleU) * hw * t, h, Mathf.sin(angleU) * hd * t);
 
-                rend.color(Color.white);
-                rend.normal(Tmp.v32.set(Tmp.v31).nor());
-                rend.texCoord(u, v);
-                rend.vertex(Tmp.v31);
+                Vertex vert = new Vertex();
+                vert.normal.set(Tmp.v32.set(Tmp.v31).nor());
+                vert.color.set(color(Tmp.v31));//set(vert.normal.x, vert.normal.y, vert.normal.z, 1f);
+                vert.uv.set(u, v);
+                vert.pos.set(Tmp.v31);
+
+                int index = vertices.size;
+                vertices.add(vert);
+
+                tmpIndices.set(tempOffset, (short)index);
+                final int o = tempOffset + s;
+                if(iv > 0 && iu > 0){
+                    indices.add(tmpIndices.get(tempOffset), tmpIndices.get((o - 1) % s), tmpIndices.get((o - (divisionsU + 2)) % s), tmpIndices.get((o - (divisionsU + 1)) % s));
+                    //builder.rect(tmpIndices.get(tempOffset), tmpIndices.get((o - 1) % s), tmpIndices.get((o - (divisionsU + 2)) % s), tmpIndices.get((o - (divisionsU + 1)) % s));
+                }
+                tempOffset = (tempOffset + 1) % tmpIndices.size;
             }
         }
     }
+
+    Color color(Vec3 v){
+        double value = sim.octaveNoise3D(6, 0.6, 1.0 / 10.0, v.x, v.y, v.z);
+        return colors[Mathf.clamp((int)(value * colors.length), 0, colors.length - 1)];
+    }
+
+    void drawSphere(){
+        for(int i = 0; i < indices.size; i += 4){
+            Vertex v1 = vertices.get(indices.get(i));
+            Vertex v2 = vertices.get(indices.get(i + 1));
+            Vertex v3 = vertices.get(indices.get(i + 2));
+            Vertex v4 = vertices.get(indices.get(i + 3));
+
+            v1.d();
+            v2.d();
+            v3.d();
+
+            v3.d();
+            v4.d();
+            v1.d();
+        }
+    }
+
+    class Vertex{
+        Color color = new Color();
+        Vec3 normal = new Vec3();
+        Vec2 uv = new Vec2();
+        Vec3 pos = new Vec3();
+
+        void d(){
+            rend.color(color);
+            rend.normal(normal);
+            rend.texCoord(uv.x, uv.y);
+            rend.vertex(pos);
+        }
+    }
 }