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在我做一个大数据集来测试之前，我想我会先挑选你的大脑，

您认为 iOS 设备的这两种 vbo 设置中哪一种更快？在 openGL-ES 1.x 环境中。

一个人设置一个空白的主 GL_ELEMENT_ARRAY_BUFFER 然后使用运行循环中的 glBufferSubData 用当时需要的任何索引数据进行子填充，

其他设置是事先设置单独的 GL_ELEMENT_ARRAY_BUFFER 并在运行循环中使用 glBindBuffer。

（在“DrawOutShape”下面的两种情况下都是运行循环中的唯一例程）

更新：供人们将来参考，我相信我在示例 3 中找到了最好的方法：（如果有错误请更正）。

快速提问：有没有更好的方法来执行此行“(GLushort*)(sizeof(GLushort)*shapetest2->deOffset)”

更新2：供人们以后参考，在伪实例化中，如果你此时要在iOS中实例化，没有办法在运行循环中设置你的数据（有很多块，然后旋转和缩放和放置）并且有一个在运行循环结束时单个 glDrawElements 以同时将它们全部绘制出来，在开始循环之前（不会使你的速度比现在更糟），你必须为你的运行循环中的每个“形状”都有一个 glDrawElements不幸的是....我已经确定openGL-ES或Apple在未来的版本中是否可以使用单个glDrawElements进行实例化，这可以显着提高FPS，比如5倍。这是一堵砖墙，阻碍了 ES 在 IMO 上的快速发展。

示例 1：

static const GLushort test2Trips[] =
{
    24, 25, 27, 25, 26, 27,
    28, 29, 31, 29, 30, 31,
    32, 33, 35, 33, 34, 35,
    36, 37, 39, 37, 38, 39,
    40, 41, 43, 41, 42, 43,
    44, 45, 47, 45, 46, 47,
    48, 49, 51, 49, 50, 51,
    52, 53, 55, 53, 54, 55,
    56, 57, 59, 57, 58, 59,
    60, 61, 63, 61, 62, 63,
    64, 65, 67, 65, 66, 67,
    68, 69, 71, 69, 70, 71,
};

//-------------------------
static inline void shapetest2Setup(void)
{
    shapetest2 = malloc(sizeof(shapeBase));
    shapetest2->stripsName[1]   = NULL;
    shapetest2->tripsName       = &test2Trips;
    shapetest2->fansName        = NULL;
    shapetest2->dataName        = &test2Data;
    shapetest2->totStrips       = 0;
    shapetest2->stripsNum[1]    = 0;
    shapetest2->tripsNum        = 72;
    shapetest2->totFans     = 0;
    shapetest2->listOfInserts   = NULL;
    shapetest2->center      = Vertex3DMake( 0.000000, -0.000000, 2.000000 );
    shapetest2->radius      = Vertex3DMake( 1.000000, 1.000000, 2.000000 );
    shapetest2->indexSize       = sizeof(test2Trips);
    shapetest2->deOffset        = 24;

    dataSize  += sizeof(test2Data);
    if (sizeof(test2Trips) > indexSize) indexSize = sizeof(test2Trips);
}

// endOfShapetest2
//--------------------------------------------------------

//-------------------------
static inline void CreateVBOs(void)
{
    GLsizeiptr theDataSize = 0;

    glGenBuffers(1, &mainBuffer);
    glBindBuffer(GL_ARRAY_BUFFER, mainBuffer);
    glBufferData(GL_ARRAY_BUFFER, dataSize, NULL, GL_STATIC_DRAW);

    glBufferSubData(GL_ARRAY_BUFFER, theDataSize, sizeof(test1Data), test1Data);
    theDataSize += sizeof(test1Data);
    glBufferSubData(GL_ARRAY_BUFFER, theDataSize, sizeof(test2Data), test2Data);

    glGenBuffers(1, &mainIndex);
    glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, mainIndex);
    glBufferData(GL_ELEMENT_ARRAY_BUFFER, indexSize, NULL, GL_STATIC_DRAW);
}


//------------------------------------------------------
static inline void DrawOutShape(void)
{
    glBufferSubData(GL_ELEMENT_ARRAY_BUFFER, 0, shapetest2->indexSize, shapetest2->tripsName);

    glDrawElements(GL_TRIANGLES, shapetest2->tripsNum, GL_UNSIGNED_SHORT, (void*)0);
}

示例 2：

static const GLushort test2Trips[] =
{
    24, 25, 27, 25, 26, 27,
    28, 29, 31, 29, 30, 31,
    32, 33, 35, 33, 34, 35,
    36, 37, 39, 37, 38, 39,
    40, 41, 43, 41, 42, 43,
    44, 45, 47, 45, 46, 47,
    48, 49, 51, 49, 50, 51,
    52, 53, 55, 53, 54, 55,
    56, 57, 59, 57, 58, 59,
    60, 61, 63, 61, 62, 63,
    64, 65, 67, 65, 66, 67,
    68, 69, 71, 69, 70, 71,
};

//-------------------------
static inline void shapetest2Setup(void)
{
    shapetest2 = malloc(sizeof(shapeBase));
    shapetest2->stripsName[1]   = NULL;
    shapetest2->tripsName       = &test2Trips;
    shapetest2->fansName        = NULL;
    shapetest2->dataName        = &test2Data;
    shapetest2->totStrips       = 0;
    shapetest2->stripsNum[1]    = 0;
    shapetest2->tripsNum        = 72;
    shapetest2->totFans     = 0;
    shapetest2->listOfInserts   = NULL;
    shapetest2->center      = Vertex3DMake( 0.000000, -0.000000, 2.000000 );
    shapetest2->radius      = Vertex3DMake( 1.000000, 1.000000, 2.000000 );
    shapetest2->indexSize       = sizeof(test2Trips);
    shapetest2->deOffset        = 24;

    dataSize  += sizeof(test2Data);
    if (sizeof(test2Trips) > indexSize) indexSize = sizeof(test2Trips);

    glGenBuffers(1, &shapetest2->indexName);
    glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, shapetest2->indexName);
    glBufferData(GL_ELEMENT_ARRAY_BUFFER, sizeof(test2Trips), test2Trips, GL_STATIC_DRAW);
}

// endOfShapetest2
//--------------------------------------------------------

//-------------------------
static inline void CreateVBOs(void)
{
    GLsizeiptr theDataSize = 0;

    glGenBuffers(1, &mainBuffer);
    glBindBuffer(GL_ARRAY_BUFFER, mainBuffer);
    glBufferData(GL_ARRAY_BUFFER, dataSize, NULL, GL_STATIC_DRAW);

    glBufferSubData(GL_ARRAY_BUFFER, theDataSize, sizeof(test1Data), test1Data);
    theDataSize += sizeof(test1Data);
    glBufferSubData(GL_ARRAY_BUFFER, theDataSize, sizeof(test2Data), test2Data);

}


//------------------------------------------------------
static inline void DrawOutShape(void)
{
    glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, shapetest2->indexName);

    glDrawElements(GL_TRIANGLES, shapetest2->tripsNum, GL_UNSIGNED_SHORT, (void*)0);
}

示例 3：

static const GLushort test1Trips[] =
{
    0, 1, 3, 1, 2, 3,
    4, 5, 7, 5, 6, 7,
    8, 9, 11, 9, 10, 11,
    12, 13, 15, 13, 14, 15,
    16, 17, 19, 17, 18, 19,
    20, 21, 23, 21, 22, 23,
};

static const GLushort test2Trips[] =
{
    24, 25, 27, 25, 26, 27,
    28, 29, 31, 29, 30, 31,
    32, 33, 35, 33, 34, 35,
    36, 37, 39, 37, 38, 39,
    40, 41, 43, 41, 42, 43,
    44, 45, 47, 45, 46, 47,
    48, 49, 51, 49, 50, 51,
    52, 53, 55, 53, 54, 55,
    56, 57, 59, 57, 58, 59,
    60, 61, 63, 61, 62, 63,
    64, 65, 67, 65, 66, 67,
    68, 69, 71, 69, 70, 71,
};

 //-------------------------
static inline void shapetest2Setup(void)
{
    shapetest2 = malloc(sizeof(shapeBase));
    shapetest2->stripsName[1]   = NULL;
    shapetest2->tripsName       = &test2Trips;
    shapetest2->fansName        = NULL;
    shapetest2->dataName        = &test2Data;
    shapetest2->totStrips       = 0;
    shapetest2->stripsNum[1]    = 0;
    shapetest2->tripsNum        = 72;
    shapetest2->totFans     = 0;
    shapetest2->listOfInserts   = NULL;
    shapetest2->center      = Vertex3DMake( 0.000000, -0.000000, 2.000000 );
    shapetest2->radius      = Vertex3DMake( 1.000000, 1.000000, 2.000000 );
    shapetest2->indexSize       = sizeof(test2Trips);
    shapetest2->deOffset        = 24;

    dataSize  += sizeof(test2Data);
    indexSize += sizeof(test2Trips);

 }

// endOfShapetest2
//--------------------------------------------------------

//-------------------------
static inline void CreateVBOs(void)
{
    GLintptr theDataOffset = 0;
    GLintptr theIndexOffset = 0;

    glGenBuffers(1, &mainBuffer);
    glBindBuffer(GL_ARRAY_BUFFER, mainBuffer);
    glBufferData(GL_ARRAY_BUFFER, dataSize, NULL, GL_STATIC_DRAW);

    glBufferSubData(GL_ARRAY_BUFFER, theDataOffset, sizeof(test1Data), test1Data);
    theDataOffset += sizeof(test1Data);
    glBufferSubData(GL_ARRAY_BUFFER, theDataOffset, sizeof(test2Data), test2Data);
    theDataOffset += sizeof(test2Data);

    glGenBuffers(1, &mainIndex);
    glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, mainIndex);
    glBufferData(GL_ELEMENT_ARRAY_BUFFER, indexSize, NULL, GL_STATIC_DRAW);

    glBufferSubData(GL_ELEMENT_ARRAY_BUFFER, theIndexOffset, sizeof(test1Trips), test1Trips);
    theIndexOffset += sizeof(test1Trips);
    glBufferSubData(GL_ELEMENT_ARRAY_BUFFER, theIndexOffset, sizeof(test2Trips), test2Trips);
    theIndexOffset += sizeof(test2Trips);
}

//------------------------------------------------------
static inline void DrawOutShape(void)
{
    glDrawElements(GL_TRIANGLES, shapetest2->tripsNum, GL_UNSIGNED_SHORT, (GLushort*)(sizeof(GLushort)*shapetest2->deOffset));
}
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