C++错误 C4700：使用未初始化的局部变量'i'

1>------ Build started: Project: RageBotGamingEngine, Configuration: Debug Win32 ------
1>  Sprite.cpp
1>c:usersnhadocumentsvisual studio 2013projectsragebotgamingengineragebotgamingenginesprite.cpp(51): error C4700: uninitialized local variable 'i' used
========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ==========

以上是输出日志所说的。以下是可能涉及此问题的一些相关文件：

雪碧.cpp

#include "Sprite.h"
#include "Vertex.h"
#include <cstddef>
Sprite::Sprite()
{
_vboID = 0;
}

Sprite::~Sprite()
{
if (_vboID != 0) {
    glDeleteBuffers(1, &_vboID);
}
}
void Sprite::init(float x, float y, float width, float height) {
_x = x;
_y = y;
_width = width;
_height = height;
if (_vboID == 0) {
    glGenBuffers(1, &_vboID);
}
Vertex vertexData[6];
//First Triangle
vertexData[0].position.x = x + width;
vertexData[0].position.y = y + width;
vertexData[1].position.x = x;
vertexData[1].position.y = y + height;
vertexData[2].position.x = x;
vertexData[2].position.y = y;
//Second Triangle
vertexData[3].position.x = x;
vertexData[3].position.y = y;
vertexData[4].position.x = x + width;
vertexData[4].position.y = y;
vertexData[5].position.x = x + width;
vertexData[5].position.y = y + height;
for (int i; i < 6; i++) {
    vertexData[i].color.r = 255;
    vertexData[i].color.g = 0;
    vertexData[i].color.b = 255;
    vertexData[i].color.a = 255;
}
glBindBuffer(GL_ARRAY_BUFFER, _vboID);
glBufferData(GL_ARRAY_BUFFER, sizeof(vertexData), vertexData, GL_STATIC_DRAW);
glBindBuffer(GL_ARRAY_BUFFER, 0);
}
void Sprite::draw() {
glBindBuffer(GL_ARRAY_BUFFER, _vboID);
glEnableVertexAttribArray(0);
//This is position attribute pointer
glVertexAttribPointer(0, 2, GL_FLOAT, GL_FALSE, sizeof(Vertex), (void*)offsetof(Vertex, position));
//This is color attribute pointer
glVertexAttribPointer(1, 4, GL_UNSIGNED_BYTE, GL_TRUE, sizeof(Vertex), (void*)offsetof(Vertex, color));
glDrawArrays(GL_TRIANGLES, 0, 6);
glDisableVertexAttribArray(0);
glBindBuffer(GL_ARRAY_BUFFER, 0);
}

我试图找到问题，但我对OpenGL，SDL和C++相对较新，正如你可以想象的那样，这是一个巨大的麻烦，因为OpenGL维基并不容易遵循和一致。几乎任何帮助都将是非常需要和赞赏的。

正在尝试创建一个游戏引擎（显然我几乎不熟练，没有时间开发这个项目）