我有一个非常简单的程序，加载的波前OBJ文件，旋转和显示。问题是，该方案的一些问题使得它（如缺少三角形）。我有一个类似的问题，当我试图呈现一个金字塔与讷河的教程采取了顶点缓冲。因此，我不知道是什么造成这种渲染的问题。你能帮助我吗？

 包com.jam.libgdx3DTest;进口com.badlogic.gdx.Game;进口com.badlogic.gdx.Gdx;进口com.badlogic.gdx.graphics *。进口com.badlogic.gdx.graphics.g3d.loaders.obj.ObjLoader;进口的java.io.InputStream;公共类Libgdx3DTest扩展游戏{    私人网shuttleMesh;    私人相机拍照;    私人浮动rotateAngle;    公共无效创建（）{        如果（shuttleMesh == NULL）{            。InputStream的时间= Gdx.files.internal（shuttle.obj）阅读（）;            shuttleMesh = ObjLoader.loadObj（以假）;        }    }    公共无效渲染（）{        Gdx.gl.glClear（GL10.GL_COLOR_BUFFER_BIT | GL10.GL_DEPTH_BUFFER_BIT）;        Gdx.gl10.glMatrixMode（GL11.GL_MODELVIEW_MATRIX）;        Gdx.gl10.glLoadIdentity（）;        camera.update（）;        camera.apply（Gdx.gl10）;        rotateAngle + = 0.5F;        Gdx.gl10.glRotatef（rotateAngle，0F，1F，0F）;        Gdx.gl10.glRotatef（-90f，1F，0F，0F）;        shuttleMesh.render（GL11.GL_TRIANGLES）;    }    公共无效调整大小（INT宽度，高度INT）{        漂浮的aspectRatio =（浮点）宽/（浮点）高度;        摄像头=新PerspectiveCamera（67，2F *的aspectRatio，2F）;        camera.translate（0F，0F，12F）;    }    公共无效暂停（）{    }    公共无效简历（）{    }    公共无效的Dispose（）{    }} 

解决方案

我想你可能是具有缠绕的问题，即该模型有不同的绕组比的OpenGL。

OpenGL的绕组逆时针默认情况下，尽管这可以glFrontFace（GL_CW）来改变;

I have a very simple program, that loads an wavefront obj file, rotate and displays it. The problem is that the program renders it with some issues (like missing triangles). I had a similar problem when I tried to render a Pyramid with a vertex buffer taken from NeHe's tutorial. So I don't know what cause this rendering issues. Can you help me?

package com.jam.libgdx3DTest;

import com.badlogic.gdx.Game;
import com.badlogic.gdx.Gdx;
import com.badlogic.gdx.graphics.*;
import com.badlogic.gdx.graphics.g3d.loaders.obj.ObjLoader;

import java.io.InputStream;

public class Libgdx3DTest extends Game {

    private Mesh shuttleMesh;
    private Camera camera;
    private float rotateAngle;

    public void create() {
        if (shuttleMesh == null) {
            InputStream in = Gdx.files.internal("shuttle.obj").read();
            shuttleMesh = ObjLoader.loadObj(in, false);
        }
    }

    public void render() {
        Gdx.gl.glClear(GL10.GL_COLOR_BUFFER_BIT | GL10.GL_DEPTH_BUFFER_BIT);

        Gdx.gl10.glMatrixMode(GL11.GL_MODELVIEW_MATRIX);

        Gdx.gl10.glLoadIdentity();

        camera.update();
        camera.apply(Gdx.gl10);

        rotateAngle += 0.5f;
        Gdx.gl10.glRotatef(rotateAngle, 0f, 1f, 0f);
        Gdx.gl10.glRotatef(-90f, 1f, 0f, 0f);

        shuttleMesh.render(GL11.GL_TRIANGLES);
    }

    public void resize(int width, int height) {
        float aspectRatio = (float) width / (float) height;
        camera = new PerspectiveCamera(67, 2f * aspectRatio, 2f);
        camera.translate(0f, 0f, 12f);
    }

    public void pause(){
    }

    public void resume(){
    }

    public void dispose() {
    }
}

I think you might be having winding issues i.e. the model has different winding than OpenGL.

OpenGL Winding is counterclockwise by default though this can be changed with glFrontFace(GL_CW);