这是我从这个链接获得的模型类 OpenGL ES Tools for Android我对它做了一些修改。这个类成功地从 .obj 文件中加载了 obj 数据，如顶点、法线、textcoords 和索引。
类模型
public class Model {
// Constants
private static final int FLOAT_SIZE_BYTES = 4;
private static final int SHORT_SIZE_BYTES = 2;
private FloatBuffer _vb;
private FloatBuffer _nb;
private ShortBuffer _ib;
private FloatBuffer _tcb;
private short[] indices;
private float[] tempV;
private float[] tempVt;
private float[] tempVn;
private ArrayList<Vector3D> vertices;
private ArrayList<Vector3D> vertexTexture;
private ArrayList<Vector3D> vertexNormal;
private ArrayList<Face> faces;
private int vertexCount;
private ArrayList<GroupObject> groupObjects;
class Vector3D {
float x, y, z;
public Vector3D(float parseFloat, float parseFloat2, float parseFloat3) {
x = parseFloat;
y = parseFloat2;
z = parseFloat3;
}
public float getX() {
return x;
}
public float getY() {
return y;
}
public float getZ() {
return z;
}
}
类人脸
class Face {
public ArrayList<Vector3D> getVertices() {
return vertices;
}
public ArrayList<Vector3D> getUvws() {
return vertexTexture;
}
public ArrayList<Vector3D> getNormals() {
return vertexNormal;
}
}
GroupObject 类
class GroupObject {
String objectName;
public void setObjectName(String string) {
this.objectName = string;
}
public String getObjectName() {
return objectName;
}
}
// Android Stuff!
private Context context;
private int modelID;
public Model(int modelID, Context activity) {
this.vertices = new ArrayList<Vector3D>();
this.vertexTexture = new ArrayList<Vector3D>();
this.vertexNormal = new ArrayList<Vector3D>();
this.faces = new ArrayList<Face>();
this.groupObjects = new ArrayList<GroupObject>();
this.modelID = modelID;
this.context = activity;
loadFile();
}
private int loadFile() {
InputStream inputStream = context.getResources().openRawResource(
modelID);
BufferedReader in = new BufferedReader(new InputStreamReader(
inputStream));
try {
loadOBJ(in);
Log.d("LOADING FILE", "FILE LOADED SUCESSFULLY====================");
} catch (IOException e) {
e.printStackTrace();
}
try {
in.close();
} catch (IOException e) {
e.printStackTrace();
}
return 1;
}
private void loadOBJ(BufferedReader in) throws IOException {
Log.d("LOADING FILE", "STARTING!====================");
GroupObject defaultObject = new GroupObject();
GroupObject currentObject = defaultObject;
this.groupObjects.add(defaultObject);
String Line; // Stores ever line we read!
String[] Blocks; // Stores string fragments after the split!!
String CommandBlock; // Stores Command Blocks such as: v, vt, vn, g,
// etc...
while ((Line = in.readLine()) != null) {
Blocks = Line.split(" ");
CommandBlock = Blocks[0];
// Log.d("COMMAND BLOCK" , "---------- " + CommandBlock +
// " ----------");
if (CommandBlock.equals("g")) {
if (Blocks[1] == "default")
currentObject = defaultObject;
else {
GroupObject groupObject = new GroupObject();
groupObject.setObjectName(Blocks[1]);
currentObject = groupObject;
groupObjects.add(groupObject);
}
}
if (CommandBlock.equals("v")) {
Vector3D vertex = new Vector3D(Float.parseFloat(Blocks[1]),
Float.parseFloat(Blocks[2]),
Float.parseFloat(Blocks[3]));
this.vertices.add(vertex);
// Log.d("VERTEX DATA", " " + vertex.getX() + ", " +
// vertex.getY() + ", " + vertex.getZ());
}
if (CommandBlock.equals("vt")) {
Vector3D vertexTex = new Vector3D(Float.parseFloat(Blocks[1]),
Float.parseFloat(Blocks[2]), 0.0f);
this.vertexTexture.add(vertexTex);
// Log.d("TEXTURE DATA", " " + vertexTex.getX() + ", " +
// vertexTex.getY() + ", " + vertexTex.getZ());
}
if (CommandBlock.equals("vn")) {
Vector3D vertexNorm = new Vector3D(Float.parseFloat(Blocks[1]),
Float.parseFloat(Blocks[2]),
Float.parseFloat(Blocks[3]));
this.vertexNormal.add(vertexNorm);
// Log.d("NORMAL DATA", " " + vertexNorm.getX() + ", " +
// vertexNorm.getY() + ", " + vertexNorm.getZ());
}
if (CommandBlock.equals("f")) {
Face face = new Face();
faces.add(face);
String[] faceParams;
for (int i = 1; i < Blocks.length; i++) {
faceParams = Blocks[i].split("/");
face.getVertices()
.add(this.vertices.get(Integer
.parseInt(faceParams[0]) - 1));
if (faceParams[1] == "") {
} else {
face.getUvws().add(
this.vertexTexture.get(Integer
.parseInt(faceParams[1]) - 1));
face.getNormals().add(
this.vertexNormal.get(Integer
.parseInt(faceParams[2]) - 1));
}
}
}
}
// fillInBuffers();
fillInBuffersWithNormals();
Log.d("OBJ OBJECT DATA", "V = " + vertices.size() + " VN = "
+ vertexTexture.size() + " VT = " + vertexNormal.size());
}
private void fillInBuffers() {
int facesSize = faces.size();
vertexCount = facesSize * 3;
tempV = new float[facesSize * 3 * 3];
tempVt = new float[facesSize * 2 * 3];
indices = new short[facesSize * 3];
for (int i = 0; i < facesSize; i++) {
Face face = faces.get(i);
tempV[i * 9] = face.getVertices().get(0).getX();
tempV[i * 9 + 1] = face.getVertices().get(0).getY();
tempV[i * 9 + 2] = face.getVertices().get(0).getZ();
tempV[i * 9 + 3] = face.getVertices().get(1).getX();
tempV[i * 9 + 4] = face.getVertices().get(1).getY();
tempV[i * 9 + 5] = face.getVertices().get(1).getZ();
tempV[i * 9 + 6] = face.getVertices().get(2).getX();
tempV[i * 9 + 7] = face.getVertices().get(2).getY();
tempV[i * 9 + 8] = face.getVertices().get(2).getZ();
tempVt[i * 6] = face.getUvws().get(0).getX();
tempVt[i * 6 + 1] = face.getUvws().get(0).getY();
tempVt[i * 6 + 2] = face.getUvws().get(1).getX();
tempVt[i * 6 + 3] = face.getUvws().get(1).getY();
tempVt[i * 6 + 4] = face.getUvws().get(2).getX();
tempVt[i * 6 + 5] = face.getUvws().get(2).getY();
indices[i * 3] = (short) (i * 3);
indices[i * 3 + 1] = (short) (i * 3 + 1);
indices[i * 3 + 2] = (short) (i * 3 + 2);
}
_vb = ByteBuffer.allocateDirect(tempV.length * FLOAT_SIZE_BYTES)
.order(ByteOrder.nativeOrder()).asFloatBuffer();
_vb.put(tempV);
_vb.position(0);
_tcb = ByteBuffer.allocateDirect(tempVt.length * FLOAT_SIZE_BYTES)
.order(ByteOrder.nativeOrder()).asFloatBuffer();
_tcb.put(tempVt);
_tcb.position(0);
_ib = ByteBuffer.allocateDirect(indices.length * SHORT_SIZE_BYTES)
.order(ByteOrder.nativeOrder()).asShortBuffer();
_ib.put(indices);
_ib.position(0);
}
private void fillInBuffersWithNormals() {
int facesSize = faces.size();
vertexCount = facesSize * 3;
tempV = new float[facesSize * 3 * 3];
tempVt = new float[facesSize * 2 * 3];
tempVn = new float[facesSize * 3 * 3];
indices = new short[facesSize * 3];
for (int i = 0; i < facesSize; i++) {
Face face = faces.get(i);
tempV[i * 9] = face.getVertices().get(0).getX();
tempV[i * 9 + 1] = face.getVertices().get(0).getY();
tempV[i * 9 + 2] = face.getVertices().get(0).getZ();
tempV[i * 9 + 3] = face.getVertices().get(1).getX();
tempV[i * 9 + 4] = face.getVertices().get(1).getY();
tempV[i * 9 + 5] = face.getVertices().get(1).getZ();
tempV[i * 9 + 6] = face.getVertices().get(2).getX();
tempV[i * 9 + 7] = face.getVertices().get(2).getY();
tempV[i * 9 + 8] = face.getVertices().get(2).getZ();
tempVn[i * 9] = face.getNormals().get(0).getX();
tempVn[i * 9 + 1] = face.getNormals().get(0).getY();
tempVn[i * 9 + 2] = face.getNormals().get(0).getZ();
tempVn[i * 9 + 3] = face.getNormals().get(1).getX();
tempVn[i * 9 + 4] = face.getNormals().get(1).getY();
tempVn[i * 9 + 5] = face.getNormals().get(1).getZ();
tempVn[i * 9 + 6] = face.getNormals().get(2).getX();
tempVn[i * 9 + 7] = face.getNormals().get(2).getY();
tempVn[i * 9 + 8] = face.getNormals().get(2).getZ();
tempVt[i * 6] = face.getUvws().get(0).getX();
tempVt[i * 6 + 1] = face.getUvws().get(0).getY();
tempVt[i * 6 + 2] = face.getUvws().get(1).getX();
tempVt[i * 6 + 3] = face.getUvws().get(1).getY();
tempVt[i * 6 + 4] = face.getUvws().get(2).getX();
tempVt[i * 6 + 5] = face.getUvws().get(2).getY();
indices[i * 3] = (short) (i * 3);
indices[i * 3 + 1] = (short) (i * 3 + 1);
indices[i * 3 + 2] = (short) (i * 3 + 2);
}
_vb = ByteBuffer.allocateDirect(tempV.length * FLOAT_SIZE_BYTES)
.order(ByteOrder.nativeOrder()).asFloatBuffer();
_vb.put(tempV);
_vb.position(0);
_tcb = ByteBuffer.allocateDirect(tempVt.length * FLOAT_SIZE_BYTES)
.order(ByteOrder.nativeOrder()).asFloatBuffer();
_tcb.put(tempVt);
_tcb.position(0);
_nb = ByteBuffer.allocateDirect(tempVn.length * FLOAT_SIZE_BYTES)
.order(ByteOrder.nativeOrder()).asFloatBuffer();
_nb.put(tempVn);
_nb.position(0);
_ib = ByteBuffer.allocateDirect(indices.length * SHORT_SIZE_BYTES)
.order(ByteOrder.nativeOrder()).asShortBuffer();
_ib.put(indices);
_ib.position(0);
}
public FloatBuffer getVertices() {
return _vb;
}
public FloatBuffer getTexCoords() {
return _tcb;
}
public ShortBuffer getIndices() {
return _ib;
}
public FloatBuffer getNormals() {
return _nb;
}
}
我的问题是，在 opengl 中的何处以及如何传递或使用我从模型类获得的数据(顶点、法线、文本坐标和索引..)。这是我在绘制函数中所做的。它是现在正确绘制对象。我是 opengl 的新手，我认为这里做错了什么(在绘制函数中)任何帮助将不胜感激。提前致谢。
MyObjModel 类
Class MyObjModel
{
// global buffers
FloatBuffer mVertexBuffer;
FloatBuffer mTextureBuffer;
FloatBuffer mNormalBuffer;
ShortBuffer mIndices;
public MyObjModel()
{
//penguin_obj is .obj file which is exported from blender
Model model = new Model(R.raw.penguin_obj,
activity);
mVertexBuffer = model.getVertices();
mTextureBuffer = model.getTexCoords();
mNormalBuffer = model.getNormals();
mIndices = model.getIndices();
}
public void draw(GL10 gl) {
gl.glVertexPointer(3, GL10.GL_FIXED, 0, mVertexBuffer);
gl.glEnable(GL10.GL_TEXTURE_2D); // workaround bug 3623
gl.glTexCoordPointer(2, GL10.GL_FIXED, 0, mTextureBuffer);
gl.glNormalPointer(1, GL10.GL_FIXED, mNormalBuffer);
// gl.glColor4f(1, 1, 1, 1);
// gl.glNormal3f(0, 0, 1);
gl.glDrawArrays(GL10.GL_TRIANGLE_STRIP, 0, mVertexBuffer.limit());
}
}
最佳答案
您没有在绘制方法中启用顶点数组。添加这个:
gl.glEnableClientState(GL10.GL_VERTEX_ARRAY);
关于android opengl 从 .obj 文件绘制 3d 模型，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/21879563/