java - 如何单独纹理化(使用不同的纹理文件)3D 模型？

Question

我有一个在 Blender 中制作的 3D 文件并导出到 java(.OBJ 文件)，该文件将其纹理分成了一些文件。在这个 .obj 文件中，它有一些名为 USEMTL 的字段及其各部分的名称(纹理文件)。但是，当我在屏幕上绘制它时，他只显示最后一个 USEMTL 名称。我的问题是:我怎样才能让他以正确的方式阅读和纹理化？不研磨其他纹理？

这是具有 .obj 加载器的类

    public MLoader(String path, Model m) throws IOException {
            @SuppressWarnings("resource")
            BufferedReader reader = new BufferedReader(new FileReader(new File(path)));
            String line;

    while ((line = reader.readLine()) != null) {
        if (line.startsWith("v ")) {
            float 
            v1 = Float.valueOf(line.split(" ")[1]), 
            v2 = Float.valueOf(line.split(" ")[2]), 
            v3 = Float.valueOf(line.split(" ")[3]);

            Vector3f v = new Vector3f (v1, v2, v3);

            m.vertex.add(v);
        } if (line.startsWith("usemtl ")){
            String name = String.valueOf(line.split(" ")[1]);
            m.nameTexture.add(name);
            continue;
        } if (line.startsWith("f ")) {
            float 
            v1 = Float.valueOf(line.split(" ")[1].split("/")[0]),
            v2 = Float.valueOf(line.split(" ")[2].split("/")[0]),
            v3 = Float.valueOf(line.split(" ")[3].split("/")[0]),

            n1 = Float.valueOf(line.split(" ")[1].split("/")[1]),
            n2 = Float.valueOf(line.split(" ")[2].split("/")[1]),
            n3 = Float.valueOf(line.split(" ")[3].split("/")[1]);

            Vector3f
            v = new Vector3f (v1, v2, v3),
            n = new Vector3f (n1, n2, n3);

            m.face.add(new Faces(v, n));
        }if (line.startsWith("vt ")) {
            float 
            vt1 = Float.valueOf(line.split(" ")[1]), 
            vt2 = Float.valueOf(line.split(" ")[2]);

            Vector2f vt = new Vector2f (vt1, vt2);

            m.vertexTexture.add(vt);
        } 
    }
}

如您所见，我创建了一个 IF 语句，只是为了获取 usemtl 内容(位于 .obj 文件内)- 纹理名称(位于单独的文件中)，只是为了看看是否可以单独绑定(bind)它们。但我很难做到这一点(也许，逻辑不在我这边)。如何进行？

其他类:

纹理类别

public class Textures {
    public Texture[] tx;

    public void setNumTex(int i) {
        tx = new Texture[i];
    }

    public void setTexture(String format, String name, int i) {
        try {
            tx[i] = TextureLoader.getTexture(format, new FileInputStream(new File("res/Textures/" + name + format)));
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    public void texturing(Vector2f ft1, Vector2f ft2, int indexx) {
        for (int i=0; i<indexx; i++) {
            tx[i].bind();
        }
        glTexCoord2f(ft1.x, ft1.y);
        glTexCoord2f(ft2.x, ft2.y);
    }
}

渲染类

public class Renderer {
    Model m;

    public void loadContent(String objPath) {
        //Everithing that is loading is been putting here
        m = Model.getModel("res/Models/" + objPath);

        m.loadTex();
    }

    public void render() {
        glEnable(GL_SMOOTH);

        m.renderModel();
    }
}

模型类

public class Model {
    Textures tx;

    List<Vector3f> vertex, norms;
    List<Vector2f> vertexTexture;
    List<Faces> face;
    List<String> nameTexture;
    String name[];

    private int numTex = 0;

    Vector2f 
    t1 = new Vector2f(), t2 = new Vector2f();

    Vector3f
    v1 = new Vector3f(), v2 = new Vector3f(), v3 = new Vector3f(),
    n1 = new Vector3f(), n2 = new Vector3f(), n3 = new Vector3f(),

    public Model(String path)throws 
    LWJGLException, FileNotFoundException, IOException {
        vertex = new ArrayList<Vector3f>();
        norms = new ArrayList<Vector3f>();
        vertexTexture = new ArrayList<Vector2f>();
        face = new ArrayList<Faces>();
        nameTexture = new ArrayList<String>();

        tx = new Textures();

        new MLoader(path, this);
    }

    public static Model getModel(String path, Vector3f position, Vector3f rotation) {
        try {
            return new Model(path, position, rotation);
        } catch (LWJGLException | IOException e) {
            e.printStackTrace();
        }
        return null;
    }

    public void loadTex() {
        name = new String[nameTexture.toArray().length];
        tx.setNumTex(nameTexture.toArray().length);

        for (int i=0; i<name.length; i++) {
            name[i] = nameTexture.get(i);
            numTex += 1;

            tx.setTexture(".TGA", name[i], i);
        }
    }

    public void renderModel() {
        glPushMatrix();
        glPolygonMode(GL_FRONT_AND_BACK, GL_DEPTH_BUFFER_BIT);
        glEnable(GL_TEXTURE_2D);
        glBegin(GL_TRIANGLES);
        {
            for (Faces f : face) {
                v1 = vertex.get((int) f.v.x - 1);
                v2 = vertex.get((int) f.v.y - 1);
                v3 = vertex.get((int) f.v.z - 1);
                n1 = vertex.get((int) f.n.x - 1);
                n2 = vertex.get((int) f.n.y - 1);
                n3 = vertex.get((int) f.n.z - 1);
                t1 = vertexTexture.get((int) f.n.x - 1); //
                t2 = vertexTexture.get((int) f.n.y - 1); // 

                //Vertexes
                glVertex3f(v1.x, v1.y-3.4f, v1.z-0.53f);
                glVertex3f(v2.x, v2.y-3.4f, v2.z-0.53f);
                glVertex3f(v3.x, v3.y-3.4f, v3.z-0.53f);

                //Normals
                glNormal3f(n1.x, n1.y-3.4f, n1.z-0.53f);
                glNormal3f(n2.x, n2.y-3.4f, n2.z-0.53f);
                glNormal3f(n3.x, n3.y-3.4f, n3.z-0.53f);

                //Texture
                tx.texturing(t1, t2, numTex);
                //tx.texturing(n1, n2, n3);             
            }
        }
        glEnd();
        glDisable(GL_TEXTURE_2D);
        glPopMatrix();
    }
}

Answer 1

我不会放置任何代码，因为您的问题对于 2 行解决方案来说非常复杂。但是这里它通常在简单的 3D 引擎中工作。网格的多重纹理意味着网格被分成 2 个或更多子网格-meshes。我不是 blender 专家，但我确信它能够像 Autodesk 3D studio max 一样导出带有子网格树的网格。现在，当您将这样的网格导入到程序中时，您应该能够解析所有网格这些子网格体分成单独的实体。每个这样的子网格体都有自己的顶点、纹理坐标和法线。发出绘制调用时，您将逐一迭代所有子网格，并在其自己的绘制调用中绘制每个子网格。因此，在每个绘制调用中，您还应该能够附加用于该特定的唯一纹理子网格。仅此而已。现在由您决定如何设计这样的系统。希望对您有所帮助。