Question

当我使用这种方法从obj文件中提取顶点数据时：

    public static ArrayList<Float> parseOBJ(File file) throws FileNotFoundException
    {
        //If a file is not given, it is null.
        if (file == null)
        {
            throw new FileNotFoundException("file not valid");
        }

        //If it is not a file, it is null.
        if (!file.isFile())
        {
            throw new FileNotFoundException("file not found");
        }

        ArrayList<Float> vertexData = new ArrayList<Float>();

        //Creates a scanner for the provided file.
        Scanner fileScanner = new Scanner(file);
        while (fileScanner.hasNextLine())
        {
            //Takes in a line
            String line = fileScanner.nextLine();

            //For lines that start with a "v"
            if (line.length() > 1 && line.charAt(0) == 'v')
            {
                //Lines split when a space is present.
                String[] lineElements = line.split(" ");
                for (int index = 1; index < lineElements.length; index += 1)
                {
                    //Checking to make sure the string is a number. Then pulls out the number.
                    float number = Float.parseFloat(lineElements[index]);
                    vertexData.add(number);
                }
            }
        }
        return vertexData;
    }

并使用此预编码代码进行渲染：

        int vboVertexHandler = 0;
        int vboColorHandler = 0;
        float[] vertexData;
        float[] colorData;
        int len = 0;
        try
        {
            ArrayList<Float> verticies = ResourceParser.parseOBJ(
                    new File("C:\\Users\\Will Stuckey\\Desktop\\cubeTri.obj"));
            len = verticies.size();
            vertexData = new float[len];
            colorData = new float[len];
            for (int i = 0; i < vertexData.length; i++)
            {
                vertexData[i] = verticies.get(i);
                colorData[i] = 1f;
            }

            System.out.print("Initializing the vertex float buffer........... ");
            FloatBuffer vertexBuffer = BufferUtils.createFloatBuffer(len);
            vertexBuffer.put(vertexData);
            System.out.print("flipping..... ");
            vertexBuffer.flip();
            System.out.println("DONE. num->" + (len));

            System.out.print("Initializing the color float buffer............ ");
            FloatBuffer colorBuffer = BufferUtils.createFloatBuffer(len);
            colorBuffer.put(colorData);
            System.out.print("flipping..... ");
            colorBuffer.flip();
            System.out.println("DONE. num->" + (len));

            System.out.print("Initializing the vertex handler................ ");
            vboVertexHandler = glGenBuffers();
            glBindBuffer(GL_ARRAY_BUFFER, vboVertexHandler);
            glBufferData(GL_ARRAY_BUFFER, vertexBuffer, GL_STATIC_DRAW);
            glBindBuffer(GL_ARRAY_BUFFER, 0);
            System.out.println("DONE. vertexBuffer->bound, vertexBuffer->static");

            System.out.print("Initializing the color handler................. ");
            vboColorHandler = glGenBuffers();
            glBindBuffer(GL_ARRAY_BUFFER, vboColorHandler);
            glBufferData(GL_ARRAY_BUFFER, colorBuffer, GL_STATIC_DRAW);
            glBindBuffer(GL_ARRAY_BUFFER, 0);
            System.out.println("DONE. colorBuffer->bound, colorBuffer->static");
        }

和这个渲染循环代码：

            glBindBuffer(GL_ARRAY_BUFFER, vboVertexHandler);
        glVertexPointer(3, GL_FLOAT, 0, 0L);

        glBindBuffer(GL_ARRAY_BUFFER, vboColorHandler);
        glColorPointer(3, GL_FLOAT, 0, 0L);

        glEnableClientState(GL_VERTEX_ARRAY);
        glEnableClientState(GL_COLOR_ARRAY);

        glDrawArrays(GL_TRIANGLES, 0, len);

        glDisableClientState(GL_COLOR_ARRAY);
        glDisableClientState(GL_VERTEX_ARRAY);

obj文件包含：

# Blender v2.69 (sub 0) OBJ File: ''
# www.blender.org
mtllib cubeTri.mtl
o Cube
v 1.000000 -1.000000 -1.000000
v 1.000000 -1.000000 1.000000
v -1.000000 -1.000000 1.000000
v -1.000000 -1.000000 -1.000000
v 1.000000 1.000000 -0.999999
v 0.999999 1.000000 1.000001
v -1.000000 1.000000 1.000000
v -1.000000 1.000000 -1.000000
usemtl Material
s off
f 1 2 4
f 5 8 6
f 1 5 2
f 2 6 3
f 3 7 4
f 5 1 8
f 2 3 4
f 8 7 6
f 5 6 2
f 6 7 3
f 7 8 4
f 1 4 8

立方体已被三角化。渲染时，大约有一半的三角形缺失，有几个没有正确映射。我以为我在某个地方犯了一个愚蠢的错误，但也许我需要法线？我知道它有很多来源，感谢您抽出时间来研究这个问题。

干杯 - 将会

Answer 1

经过深入搜索后，Wavefront OBJ文件不会将顶点导出为三角形或三角形条带。顶点和法线只是必须与面定义进行比较的列表。我正在编写代码来解析面部，并很快就会给它一个镜头。希望未来有人能看到这一点。完成后会添加代码。

更新：

我编写并测试了OBJ解析器。它可以工作，但仅适用于已使用三角形面导出的模型。仍在努力让非三角模型发挥作用。无论如何，代码可以在这里找到：

https://github.com/guyfleeman/rayburn/blob/master/src/rayburn/game/util/ResourceParser.java

这里的实施：

https://github.com/guyfleeman/rayburn/blob/master/src/rayburn/engine/Engine.java

为什么我的三角形立方体在lwjgl中无法正确渲染？

1 个答案: