java - Opengl es 与 obj 加载器失真

Question

我今天刚刚开始学习 OpenGL ES(我已经了解 WebGL 和 OpenGL)，以便我可以继续我在 reddit 上发布的游戏项目 (reddit.com/r/gameideas/comments/3dsy8m/revolt/)，并尝试移植我的 OBJLoader，但遇到了一个我无法解决的问题，想知道是否有人知道出了什么问题。我猜测它通常在 OpenGL 中默认启用，但在 OpenGL ES 中则不然。

这是扭曲的图像:

这是重要的代码: http://pastebin.com/1CgsJv21

public class GLMesh{
    public static Activity activity;
    private FloatBuffer verticesBuffer;
    private FloatBuffer texcoordsBuffer;
    private FloatBuffer normalsBuffer;
    private float[] vertices;
    private float[] texcoords;
    private float[] normals;
    private int numOfVertices;

    public GLMesh(){
        numOfVertices = 0;
    }

    public void setVertices(float[] vertices) {
        this.vertices = vertices;
    }

    public void setTexcoords(float[] texcoords) {
        this.texcoords = texcoords;
    }

    public void setNormals(float[] normals) {
        this.normals = normals;
    }

    private static FloatBuffer asBuffer(float[] data){
        ByteBuffer vbb = ByteBuffer.allocateDirect(data.length * 4);
        vbb.order(ByteOrder.nativeOrder());
        FloatBuffer outBuffer = vbb.asFloatBuffer();
        outBuffer.put(data);
        outBuffer.position(0);
        return outBuffer;
    }

    public void load(String path){
        // Define List of Vertices
        ArrayList<GLVec3f> rVerts = new ArrayList<>();
        ArrayList<GLVec2f> rTexs = new ArrayList<>();
        ArrayList<GLVec3f> rNorms = new ArrayList<>();
        ArrayList<GLVec3f> rTris = new ArrayList<>();
        // Add Null Vertex
        rVerts.add(null);
        rTexs.add(null);
        rNorms.add(null);
        try{
            InputStream in = activity.getAssets().open(path);
            InputStreamReader isr = new InputStreamReader(in, "UTF-8");
            BufferedReader br = new BufferedReader(isr);
            String line;
            while((line = br.readLine()) != null){
                String[] splitLine = line.split(" ");
                switch(splitLine[0]){
                    case "v":
                        float vX = Float.parseFloat(splitLine[1]);
                        float vY = Float.parseFloat(splitLine[2]);
                        float vZ = Float.parseFloat(splitLine[3]);
                        GLVec3f vertex = new GLVec3f(vX, vY, vZ);
                        rVerts.add(vertex);
                        break;
                    case "vt":
                        float tS = Float.parseFloat(splitLine[1]);
                        float tT = Float.parseFloat(splitLine[2]);
                        GLVec2f texcoord = new GLVec2f(tS, tT);
                        rTexs.add(texcoord);
                        break;
                    case "vn":
                        float nX = Float.parseFloat(splitLine[1]);
                        float nY = Float.parseFloat(splitLine[2]);
                        float nZ = Float.parseFloat(splitLine[3]);
                        GLVec3f normal = new GLVec3f(nX, nY, nZ);
                        rNorms.add(normal);
                        break;
                    case "f":
                        String[] vtn1 = splitLine[1].split("/");
                        String[] vtn2 = splitLine[2].split("/");
                        String[] vtn3 = splitLine[3].split("/");

                        float vIA = Float.parseFloat(vtn1[0]);
                        float vIB = Float.parseFloat(vtn2[0]);
                        float vIC = Float.parseFloat(vtn3[0]);

                        float tIA = Float.parseFloat(vtn1[1]);
                        float tIB = Float.parseFloat(vtn2[1]);
                        float tIC = Float.parseFloat(vtn3[1]);

                        float nIA = Float.parseFloat(vtn1[2]);
                        float nIB = Float.parseFloat(vtn2[2]);
                        float nIC = Float.parseFloat(vtn3[2]);

                        GLVec3f indexA = new GLVec3f(vIA, tIA, nIA);
                        GLVec3f indexB = new GLVec3f(vIB, tIB, nIB);
                        GLVec3f indexC = new GLVec3f(vIC, tIC, nIC);

                        rTris.add(indexA);
                        rTris.add(indexB);
                        rTris.add(indexC);
                        break;
                }
            }
        }
        catch(IOException e){
            System.err.printf("Failed to fetch mesh @ %s", path);
            return;
        }
        // Put Data into useful format
        float[] verts = new float[rTris.size() * 3];
        float[] texs = new float[rTris.size() * 2];
        float[] norms = new float[rTris.size() * 3];
        int i = 0;
        // Get rid of need for indices
        for(GLVec3f index: rTris){
            // Collect Vertex Indices
            int vI = (int) index.x;
            int tI = (int) index.y;
            int nI = (int) index.z;
            // Collect Vertex Info
            GLVec3f v = rVerts.get(vI);
            GLVec2f t = rTexs.get(tI);
            GLVec3f n = rNorms.get(nI);
            // Populate arrays
            verts[i * 3 + 0] = v.x;
            verts[i * 3 + 1] = v.y;
            verts[i * 3 + 2] = v.z;
            texs[i * 2 + 0] = t.x;
            texs[i * 2 + 1] = t.y;
            norms[i * 3 + 0] = n.x;
            norms[i * 3 + 1] = n.y;
            norms[i * 3 + 2] = n.z;
            // Increment Counter
            i++;
        }
        numOfVertices = verts.length;
        // Populate Mesh
        setVertices(verts);
        setTexcoords(texs);
        setNormals(norms);
        compile();
    }

    public void compile(){
        verticesBuffer = asBuffer(vertices);
        texcoordsBuffer = asBuffer(texcoords);
        normalsBuffer = asBuffer(normals);
    }

    public void draw(GL10 gl){
        gl.glEnableClientState(GL10.GL_VERTEX_ARRAY);
        gl.glEnableClientState(GL10.GL_TEXTURE_COORD_ARRAY);
        gl.glEnableClientState(GL10.GL_NORMAL_ARRAY);

        gl.glVertexPointer(3, GL10.GL_FLOAT, 0, verticesBuffer);
        gl.glTexCoordPointer(2, GL10.GL_FLOAT, 0, texcoordsBuffer);
        gl.glNormalPointer(GL10.GL_FLOAT, 0, normalsBuffer);
        gl.glDrawArrays(GL10.GL_TRIANGLES, 0, numOfVertices);

        gl.glDisableClientState(GL10.GL_NORMAL_ARRAY);
        gl.glDisableClientState(GL10.GL_TEXTURE_COORD_ARRAY);
        gl.glDisableClientState(GL10.GL_VERTEX_ARRAY);
    }
}

Answer 1

第三个参数传递给glDrawArrays是要渲染的索引(例如顶点)的数量。因此 numOfVertices 应该设置为已写入 verts 的顶点数，而不是 verts 中的 float :

numOfVertices = i;