Ios 新手：使用有序顶点数组绘制OpenGL ES形状

我是OpenGL ES新手，但对Objective-C和iOS开发非常有经验。到目前为止，通过定义顶点数组和相应的标记数组，我使用顶点缓冲区对象绘制和着色形状没有问题，代码如下

GLuint vertexBuffer;
glGenBuffers(1, &vertexBuffer);
glBindBuffer(GL_ARRAY_BUFFER, vertexBuffer);
glBufferData(GL_ARRAY_BUFFER, sizeof(Verticies), Verticies, GL_STATIC_DRAW);

GLuint indexBuffer;
glGenBuffers(1, &indexBuffer);
glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, indexBuffer);
glBufferData(GL_ELEMENT_ARRAY_BUFFER, sizeof(Indices), Indices, GL_STATIC_DRAW);

然后使用以下代码绘制到屏幕：

glDrawElements(GL_TRIANGLES, sizeof(Indices)/sizeof(Indices[0]), GL_UNSIGNED_BYTE, 0);
[_context presentRenderbuffer:GL_RENDERBUFFER];

对于我可以在代码中定义自己的基本形状，这一切都很好。现在我已经有人生成了从3D图形程序导出的.h文件，其中包含定义形状所需的信息，但不包含索引数组。相反，索引信息以某种方式嵌入到顶点数组中。顶点数组具有重复的坐标，这些坐标定义了绘制它们的顺序。请参见下面的示例代码。我现在还有一个法线数组和一个纹理坐标数组。有人能告诉我（或给我指一个教程/指南）我将如何使用（阅读：绘制）这些数据，而不是像以前那样使用单独的顶点/索引数组吗？提前谢谢

#define poleNumVerts 276

static const float poleVerts [] = {
  // f 1/1/1 2/2/2 3/3/3
  -0.0170377877807436, -0.00478429549256308, 0.5,
  -0.0170377877807436, 0.00409214741631937, 0.5,
  -0.0176220932500109, -0.00034605799118996, 0.5,
  // f 2/2/2 1/1/1 4/4/4
  -0.0170377877807436, 0.00409214741631937, 0.5,
  -0.0170377877807436, -0.00478429549256308, 0.5,
  -0.015324690688248, -0.00892006666692703, 0.5,
  // f 2/2/2 4/4/4 5/5/5
  -0.0170377877807436, 0.00409214741631937, 0.5,
  -0.015324690688248, -0.00892006666692703, 0.5,
  -0.015324690688248, 0.00822795297696595, 0.5,
  // f 5/5/5 4/4/4 6/6/6
  -0.015324690688248, 0.00822795297696595, 0.5,
  -0.015324690688248, -0.00892006666692703, 0.5,
  -0.012599557156627, 0.0117794232669002, 0.5,
  // f 6/6/6 4/4/4 7/7/7
  -0.012599557156627, 0.0117794232669002, 0.5,
  -0.015324690688248, -0.00892006666692703, 0.5,
  -0.012599557156627, -0.0124715369568613, 0.5,
  // f 6/6/6 7/7/7 8/8/8
  -0.012599557156627, 0.0117794232669002, 0.5,
  -0.012599557156627, -0.0124715369568613, 0.5,
  -0.0090480845742739, -0.015196688827833, 0.5,

  ...... <code truncated>... };


static const float poleNormals [] = {
  // f 1/1/1 2/2/2 3/3/3
  0, 0, 1,
  0, 0, 1,
  0, 0, 1,
  // f 2/2/2 1/1/1 4/4/4
  0, 0, 1,
  0, 0, 1,
  0, 0, 1,
  // f 2/2/2 4/4/4 5/5/5
  0, 0, 1,
  0, 0, 1,
  0, 0, 1,
  // f 5/5/5 4/4/4 6/6/6
  0, 0, 1,
  0, 0, 1,
  0, 0, 1,
  // f 6/6/6 4/4/4 7/7/7
  0, 0, 1,
  0, 0, 1,
  0, 0, 1,
  // f 6/6/6 7/7/7 8/8/8
  0, 0, 1,
  0, 0, 1,
  0, 0, 1,
  // f 6/6/6 8/8/8 9/9/9

  ...... <code truncated>...};

static const float poleTexCoords [] = {
  // f 1/1/1 2/2/2 3/3/3
  0.939514, 0.37333,
  0.928115, 0.619208,
  0.950000, 0.49702,
  // f 2/2/2 1/1/1 4/4/4
  0.928115, 0.619208,
  0.939514, 0.37333,
  0.897372, 0.25657,
  // f 2/2/2 4/4/4 5/5/5
  0.928115, 0.619208,
  0.897372, 0.25657,
  0.875352, 0.73157,
  // f 5/5/5 4/4/4 6/6/6
  0.875352, 0.73157,
  0.897372, 0.25657,
  0.795305, 0.826446,
  // f 6/6/6 4/4/4 7/7/7
  0.795305, 0.826446,
  0.897372, 0.25657,
  0.826446, 0.154695,
  // f 6/6/6 7/7/7 8/8/8
  0.795305, 0.826446,
  0.826446, 0.154695,
  0.731570, 0.074647,
  // f 6/6/6 8/8/8 9/9/9
  0.795305, 0.826446,
  0.731570, 0.074647,
  0.693430, 0.897371,

  ..... <code truncated>.... };

#定义poleNumVerts 276
静态常数浮点极数[]={
//f 1/1/12/2/23/3/3
-0.0170377877807436, -0.00478429549256308, 0.5,
-0.0170377877807436, 0.00409214741631937, 0.5,
-0.0176220932500109, -0.00034605799118996, 0.5,
//f 2/2/2 1/1/1 4/4
-0.0170377877807436, 0.00409214741631937, 0.5,
-0.0170377877807436, -0.00478429549256308, 0.5,
-0.015324690688248, -0.00892006666692703, 0.5,
//f 2/2/2 4/4/4 5/5
-0.0170377877807436, 0.00409214741631937, 0.5,
-0.015324690688248, -0.00892006666692703, 0.5,
-0.015324690688248, 0.00822795297696595, 0.5,
//f 5/5/5 4/4/4 6/6
-0.015324690688248, 0.00822795297696595, 0.5,
-0.015324690688248, -0.00892006666692703, 0.5,
-0.012599557156627, 0.0117794232669002, 0.5,
//f 6/6/6 4/4/4 7/7
-0.012599557156627, 0.0117794232669002, 0.5,
-0.015324690688248, -0.00892006666692703, 0.5,
-0.012599557156627, -0.0124715369568613, 0.5,
//f 6/6/6 7/7/7 8/8
-0.012599557156627, 0.0117794232669002, 0.5,
-0.012599557156627, -0.0124715369568613, 0.5,
-0.0090480845742739, -0.015196688827833, 0.5,
…<代码截断>…}；
静态常数浮点极数[]={
//f 1/1/12/2/23/3/3
0, 0, 1,
0, 0, 1,
0, 0, 1,
//f 2/2/2 1/1/1 4/4
0, 0, 1,
0, 0, 1,
0, 0, 1,
//f 2/2/2 4/4/4 5/5
0, 0, 1,
0, 0, 1,
0, 0, 1,
//f 5/5/5 4/4/4 6/6
0, 0, 1,
0, 0, 1,
0, 0, 1,
//f 6/6/6 4/4/4 7/7
0, 0, 1,
0, 0, 1,
0, 0, 1,
//f 6/6/6 7/7/7 8/8
0, 0, 1,
0, 0, 1,
0, 0, 1,
//f 6/6/6 8/8/8 9/9
…<代码截断>…}；
静态常数浮点极坐标[]={
//f 1/1/12/2/23/3/3
0.939514, 0.37333,
0.928115, 0.619208,
0.950000, 0.49702,
//f 2/2/2 1/1/1 4/4
0.928115, 0.619208,
0.939514, 0.37333,
0.897372, 0.25657,
//f 2/2/2 4/4/4 5/5
0.928115, 0.619208,
0.897372, 0.25657,
0.875352, 0.73157,
//f 5/5/5 4/4/4 6/6
0.875352, 0.73157,
0.897372, 0.25657,
0.795305, 0.826446,
//f 6/6/6 4/4/4 7/7
0.795305, 0.826446,
0.897372, 0.25657,
0.826446, 0.154695,
//f 6/6/6 7/7/7 8/8
0.795305, 0.826446,
0.826446, 0.154695,
0.731570, 0.074647,
//f 6/6/6 8/8/8 9/9
0.795305, 0.826446,
0.731570, 0.074647,
0.693430, 0.897371,
..…<代码截断>…}；

如果没有索引列表，那么很可能需要按顺序绘制所有顶点。您可以使用

glDrawArrays

而不是

glDrawElements

来执行此操作。它们是相同的，但前者不使用索引数组（这相当于将

{0，1，2，3，…}

的索引数组传递给

glpaurements

）