Question

我有一些xyz顶点的数组，我想要渲染它们以形成3d形状的面。这个数组最终将基于输入数据，但是现在我使用的是一个示例数组。

目前我通过一次索引三个顶点来绘制形状以制作一系列三角形，但我真的希望有一种方法（通过使用循环或其他东西）来识别相邻顶点并自动形成三角形或三角形条。

到目前为止，这是我的代码：任何关于如何实现它的帮助代替一次索引三个顶点＆＃34;真的很感激。

public class ShapeDraw{
private FloatBuffer vertexBuffer;  // Buffer for vertex-array
private FloatBuffer colorBuffer;   // Buffer for color-array
private ByteBuffer indexBuffer;    // Buffer for index-array

private float[] vertices = { // 9 vertices of the shape in (y,z,x)
    0.0f, 0.37150f, 0.5f,  // 1
    0.35f, 0.3715f, 0.35f,  // 2
    0.50f, 0.37150f, 0.0f,  // 3
    0.35f, 0.3715f, -0.35f,  // 4
    0.0f, 0.3710f, -0.5f,  // 5
    -0.35f, 0.3715f,  -0.35f,  // 6
    -0.50f, 0.3715f,  0.f,  // 7
    0.0f, -0.22f,  0.0f,  // 0
    -0.35f,  0.3715f,  0.35f   // 8
};

private float[] colors = {  // Colors of the 9 vertices in RGBA
    0.0f, 0.0f, 1.0f, 1.0f,  // 0. blue
    0.0f, 1.0f, 0.0f, 1.0f,  // 1. green
    0.0f, 0.0f, 1.0f, 1.0f,  // 2. blue
    0.0f, 1.0f, 0.0f, 1.0f,  // 3. green
    0.0f, 0.0f, 1.0f, 1.0f,  // 4. blue
    0.0f, 1.0f, 0.0f, 1.0f,  // 5. green
    0.0f, 0.0f, 1.0f, 1.0f,  // 6. blue
    0.0f, 1.0f, 0.0f, 1.0f,  // 7. green
    1.0f, 0.0f, 0.0f, 1.0f   // 8. red
};

private byte[] indices = { // Vertex indices of the 8 Triangles
    0, 7, 1,   
    1, 7, 2,   
    2, 7, 3,   
    3, 7, 4,   
    4, 7, 5,   
    5, 7, 6,   
    6, 7, 8,   
    8, 7, 0,  
    0, 4, 2, 
    0, 4, 6
};

// Constructor - Set up the buffers
public ShapeDraw() {
    // Setup vertex-array buffer. Vertices in float. An float has 4 bytes
    ByteBuffer vbb = ByteBuffer.allocateDirect(vertices.length * 4);
    vbb.order(ByteOrder.nativeOrder()); // Use native byte order
    vertexBuffer = vbb.asFloatBuffer(); // Convert from byte to float
    vertexBuffer.put(vertices);         // Copy data into buffer
    vertexBuffer.position(0);           // Rewind

    // Setup color-array buffer. Colors in float. An float has 4 bytes
    ByteBuffer cbb = ByteBuffer.allocateDirect(colors.length * 4);
    cbb.order(ByteOrder.nativeOrder());
    colorBuffer = cbb.asFloatBuffer();
    colorBuffer.put(colors);
    colorBuffer.position(0);

    // Setup index-array buffer. Indices in byte.
    indexBuffer = ByteBuffer.allocateDirect(indices.length);
    indexBuffer.put(indices);
    indexBuffer.position(0);
}

// Draw the shape
public void draw(GL10 gl) {
    gl.glFrontFace(GL10.GL_CCW);  // Front face in counter-clockwise orientation

    // Enable arrays and define their buffers
    gl.glEnableClientState(GL10.GL_VERTEX_ARRAY);
    gl.glVertexPointer(3, GL10.GL_FLOAT, 0, vertexBuffer);
    gl.glEnableClientState(GL10.GL_COLOR_ARRAY);
    gl.glColorPointer(4, GL10.GL_FLOAT, 0, colorBuffer);

    gl.glDrawElements(GL10.GL_TRIANGLES, indices.length, GL10.GL_UNSIGNED_BYTE,
                      indexBuffer);

    gl.glDisableClientState(GL10.GL_VERTEX_ARRAY);
    gl.glDisableClientState(GL10.GL_COLOR_ARRAY);
}

}

OpenGL如何从数组顶点生成网格

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