model viewer: load normals and enable cull face

cache/src/main/java/net/runelite/cache/definitions/ModelDefinition.java

@@ -1,5 +1,8 @@
 package net.runelite.cache.definitions;
 
+import net.runelite.cache.models.FaceNormal;
+import net.runelite.cache.models.VertexNormal;
+
 public class ModelDefinition
 {
 	public short[] texTriangleX;
@@ -41,5 +44,103 @@ public class ModelDefinition
 	public int anInt2595;
 	public int vertexCount = 0;
 	public short[] texturePrimaryColor;
+	public VertexNormal[] normals;
+	public FaceNormal[] faceNormals;
+
+	public void computeNormals()
+	{
+		if (this.normals != null)
+		{
+			return;
+		}
+
+		this.normals = new VertexNormal[this.vertexCount];
+
+		int var1;
+		for (var1 = 0; var1 < this.vertexCount; ++var1)
+		{
+			this.normals[var1] = new VertexNormal();
+		}
+
+		for (var1 = 0; var1 < this.triangleFaceCount; ++var1)
+		{
+			int vertexA = this.trianglePointsX[var1];
+			int vertexB = this.trianglePointsY[var1];
+			int vertexC = this.trianglePointsZ[var1];
+
+			int xA = this.vertexX[vertexB] - this.vertexX[vertexA];
+			int yA = this.vertexY[vertexB] - this.vertexY[vertexA];
+			int zA = this.vertexZ[vertexB] - this.vertexZ[vertexA];
+
+			int xB = this.vertexX[vertexC] - this.vertexX[vertexA];
+			int yB = this.vertexY[vertexC] - this.vertexY[vertexA];
+			int zB = this.vertexZ[vertexC] - this.vertexZ[vertexA];
+
+			// Compute cross product
+			int var11 = yA * zB - yB * zA;
+			int var12 = zA * xB - zB * xA;
+			int var13 = xA * yB - xB * yA;
+
+			while (var11 > 8192 || var12 > 8192 || var13 > 8192 || var11 < -8192 || var12 < -8192 || var13 < -8192)
+			{
+				var11 >>= 1;
+				var12 >>= 1;
+				var13 >>= 1;
+			}
+
+			int length = (int) Math.sqrt((double) (var11 * var11 + var12 * var12 + var13 * var13));
+			if (length <= 0)
+			{
+				length = 1;
+			}
+
+			var11 = var11 * 256 / length;
+			var12 = var12 * 256 / length;
+			var13 = var13 * 256 / length;
+
+			byte var15;
+			if (this.faceRenderType == null)
+			{
+				var15 = 0;
+			}
+			else
+			{
+				var15 = this.faceRenderType[var1];
+			}
+
+			if (var15 == 0)
+			{
+				VertexNormal var16 = this.normals[vertexA];
+				var16.x += var11;
+				var16.y += var12;
+				var16.z += var13;
+				++var16.magnitude;
+
+				var16 = this.normals[vertexB];
+				var16.x += var11;
+				var16.y += var12;
+				var16.z += var13;
+				++var16.magnitude;
+
+				var16 = this.normals[vertexC];
+				var16.x += var11;
+				var16.y += var12;
+				var16.z += var13;
+				++var16.magnitude;
+			}
+			else if (var15 == 1)
+			{
+				if (this.faceNormals == null)
+				{
+					this.faceNormals = new FaceNormal[this.triangleFaceCount];
+				}
+
+				FaceNormal var17 = this.faceNormals[var1] = new FaceNormal();
+				var17.x = var11;
+				var17.y = var12;
+				var17.z = var13;
+			}
+		}
+	}
 
 }

cache/src/main/java/net/runelite/cache/definitions/loaders/ModelLoader.java

@@ -18,6 +18,8 @@ public class ModelLoader
 			this.load2(def, var1);
 		}
 
+		def.computeNormals();
+
 		return def;
 	}
 

cache/src/main/java/net/runelite/cache/models/FaceNormal.java

@@ -0,0 +1,8 @@
+package net.runelite.cache.models;
+
+public class FaceNormal
+{
+	public int x;
+	public int y;
+	public int z;
+}

cache/src/main/java/net/runelite/cache/models/Vector3f.java

@@ -0,0 +1,8 @@
+package net.runelite.cache.models;
+
+public class Vector3f
+{
+	public float x;
+	public float y;
+	public float z;
+}

cache/src/main/java/net/runelite/cache/models/VertexNormal.java

@@ -0,0 +1,30 @@
+package net.runelite.cache.models;
+
+public class VertexNormal
+{
+	public int x;
+	public int y;
+	public int z;
+	public int magnitude;
+
+	public Vector3f normalize()
+	{
+		Vector3f v = new Vector3f();
+
+		int length = (int) Math.sqrt((double) (x * x + y * y + z * z));
+		if (length == 0)
+		{
+			length = 1;
+		}
+
+		v.x = (float) x / length;
+		v.y = (float) y / length;
+		v.z = (float) z / length;
+
+		assert v.x >= -1f && v.x <= 1f;
+		assert v.y >= -1f && v.y <= 1f;
+		assert v.z >= -1f && v.z <= 1f;
+
+		return v;
+	}
+}