1 package com.jme3.effect.shapes; 2 3 import com.jme3.math.FastMath; 4 import com.jme3.math.Vector3f; 5 import com.jme3.scene.Mesh; 6 import com.jme3.scene.VertexBuffer.Type; 7 import com.jme3.util.BufferUtils; 8 import java.util.ArrayList; 9 import java.util.List; 10 11 /** 12 * This emiter shape emits the particles from the given shape's faces. 13 * @author Marcin Roguski (Kaelthas) 14 */ 15 public class EmitterMeshFaceShape extends EmitterMeshVertexShape { 16 17 /** 18 * Empty constructor. Sets nothing. 19 */ EmitterMeshFaceShape()20 public EmitterMeshFaceShape() { 21 } 22 23 /** 24 * Constructor. It stores a copy of vertex list of all meshes. 25 * @param meshes 26 * a list of meshes that will form the emitter's shape 27 */ EmitterMeshFaceShape(List<Mesh> meshes)28 public EmitterMeshFaceShape(List<Mesh> meshes) { 29 super(meshes); 30 } 31 32 @Override setMeshes(List<Mesh> meshes)33 public void setMeshes(List<Mesh> meshes) { 34 this.vertices = new ArrayList<List<Vector3f>>(meshes.size()); 35 this.normals = new ArrayList<List<Vector3f>>(meshes.size()); 36 for (Mesh mesh : meshes) { 37 Vector3f[] vertexTable = BufferUtils.getVector3Array(mesh.getFloatBuffer(Type.Position)); 38 int[] indices = new int[3]; 39 List<Vector3f> vertices = new ArrayList<Vector3f>(mesh.getTriangleCount() * 3); 40 List<Vector3f> normals = new ArrayList<Vector3f>(mesh.getTriangleCount()); 41 for (int i = 0; i < mesh.getTriangleCount(); ++i) { 42 mesh.getTriangle(i, indices); 43 vertices.add(vertexTable[indices[0]]); 44 vertices.add(vertexTable[indices[1]]); 45 vertices.add(vertexTable[indices[2]]); 46 normals.add(FastMath.computeNormal(vertexTable[indices[0]], vertexTable[indices[1]], vertexTable[indices[2]])); 47 } 48 this.vertices.add(vertices); 49 this.normals.add(normals); 50 } 51 } 52 53 /** 54 * This method fills the point with coordinates of randomly selected point on a random face. 55 * @param store 56 * the variable to store with coordinates of randomly selected selected point on a random face 57 */ 58 @Override getRandomPoint(Vector3f store)59 public void getRandomPoint(Vector3f store) { 60 int meshIndex = FastMath.nextRandomInt(0, vertices.size() - 1); 61 // the index of the first vertex of a face (must be dividable by 3) 62 int vertIndex = FastMath.nextRandomInt(0, vertices.get(meshIndex).size() / 3 - 1) * 3; 63 // put the point somewhere between the first and the second vertex of a face 64 float moveFactor = FastMath.nextRandomFloat(); 65 store.set(Vector3f.ZERO); 66 store.addLocal(vertices.get(meshIndex).get(vertIndex)); 67 store.addLocal((vertices.get(meshIndex).get(vertIndex + 1).x - vertices.get(meshIndex).get(vertIndex).x) * moveFactor, (vertices.get(meshIndex).get(vertIndex + 1).y - vertices.get(meshIndex).get(vertIndex).y) * moveFactor, (vertices.get(meshIndex).get(vertIndex + 1).z - vertices.get(meshIndex).get(vertIndex).z) * moveFactor); 68 // move the result towards the last face vertex 69 moveFactor = FastMath.nextRandomFloat(); 70 store.addLocal((vertices.get(meshIndex).get(vertIndex + 2).x - store.x) * moveFactor, (vertices.get(meshIndex).get(vertIndex + 2).y - store.y) * moveFactor, (vertices.get(meshIndex).get(vertIndex + 2).z - store.z) * moveFactor); 71 } 72 73 /** 74 * This method fills the point with coordinates of randomly selected point on a random face. 75 * The normal param is filled with selected face's normal. 76 * @param store 77 * the variable to store with coordinates of randomly selected selected point on a random face 78 * @param normal 79 * filled with selected face's normal 80 */ 81 @Override getRandomPointAndNormal(Vector3f store, Vector3f normal)82 public void getRandomPointAndNormal(Vector3f store, Vector3f normal) { 83 int meshIndex = FastMath.nextRandomInt(0, vertices.size() - 1); 84 // the index of the first vertex of a face (must be dividable by 3) 85 int faceIndex = FastMath.nextRandomInt(0, vertices.get(meshIndex).size() / 3 - 1); 86 int vertIndex = faceIndex * 3; 87 // put the point somewhere between the first and the second vertex of a face 88 float moveFactor = FastMath.nextRandomFloat(); 89 store.set(Vector3f.ZERO); 90 store.addLocal(vertices.get(meshIndex).get(vertIndex)); 91 store.addLocal((vertices.get(meshIndex).get(vertIndex + 1).x - vertices.get(meshIndex).get(vertIndex).x) * moveFactor, (vertices.get(meshIndex).get(vertIndex + 1).y - vertices.get(meshIndex).get(vertIndex).y) * moveFactor, (vertices.get(meshIndex).get(vertIndex + 1).z - vertices.get(meshIndex).get(vertIndex).z) * moveFactor); 92 // move the result towards the last face vertex 93 moveFactor = FastMath.nextRandomFloat(); 94 store.addLocal((vertices.get(meshIndex).get(vertIndex + 2).x - store.x) * moveFactor, (vertices.get(meshIndex).get(vertIndex + 2).y - store.y) * moveFactor, (vertices.get(meshIndex).get(vertIndex + 2).z - store.z) * moveFactor); 95 normal.set(normals.get(meshIndex).get(faceIndex)); 96 } 97 } 98