紋理是一種GL對象，創(chuàng)建方式與頂點數(shù)據(jù)類似
int width_, height_;
unsigned char* image = SOIL_load_image("container.jpg", &width_, &height_, 0, SOIL_LOAD_RGB);
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, width_, height_, 0, GL_RGB, GL_UNSIGNED_BYTE, image);
glGenerateMipmap(GL_TEXTURE_2D);
SOIL_free_image_data(image);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
glBindTexture(GL_TEXTURE_2D, 0);
紋理顯示到fragment前，還需要設(shè)置它的紋理坐標(biāo)榆芦。
紋理坐標(biāo)和頂點坐標(biāo)有點不同柄粹，它指的是紋理的映射點。紋理像素（Texile）和屏幕像素不是一一對應(yīng)的
// Set up vertex data (and buffer(s)) and attribute pointers
GLfloat vertices[] = {
// ---- 位置 ---- ---- 顏色 ---- - 紋理坐標(biāo) -
0.5f, 0.5f, 0.0f, 1.0f, 0.0f, 0.0f, 1.0f, 1.0f,
0.5f, -0.5f, 0.0f, 0.0f, 1.0f, 0.0f, 1.0f, 0.0f, // 右下
-0.5f, -0.5f, 0.0f, 0.0f, 0.0f, 1.0f, 0.0f, 0.0f, // 左下
-0.5f, 0.5f, 0.0f, 1.0f, 1.0f, 0.0f, 0.0f, 1.0f, // 左上
0.5f, 0.5f, 0.0f, 1.0f, 0.0f, 0.0f, 1.0f, 1.0f, // 右上
-0.5f, -0.5f, 0.0f, 0.0f, 0.0f, 1.0f, 0.0f, 0.0f, // 左下
};
GLuint VBO, VAO;
glGenVertexArrays(1, &VAO);
glGenBuffers(1, &VBO);
// Bind the Vertex Array Object first, then bind and set vertex buffer(s) and attribute pointer(s).
glBindVertexArray(VAO);
glBindBuffer(GL_ARRAY_BUFFER, VBO);
glBufferData(GL_ARRAY_BUFFER, sizeof(vertices), vertices, GL_STATIC_DRAW);
glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 8 * sizeof(GLfloat), (GLvoid*)0);
glEnableVertexAttribArray(0);
glVertexAttribPointer(1, 3, GL_FLOAT, GL_FALSE, 8 * sizeof(GLfloat), (GLvoid*)(3 * sizeof(GLfloat)));
glEnableVertexAttribArray(1);
glVertexAttribPointer(2, 2, GL_FLOAT,GL_FALSE, 8 * sizeof(GLfloat), (GLvoid*)(6 * sizeof(GLfloat)));
glEnableVertexAttribArray(2);
glBindBuffer(GL_ARRAY_BUFFER, 0); // Note that this is allowed, the call to glVertexAttribPointer registered VBO as the currently bound vertex buffer object so afterwards we can safely unbind
glBindVertexArray(0); // Unbind VAO (it's always a good thing to unbind any buffer/array to prevent strange bugs)
這段代碼里匆绣，我們把頂點位置驻右、顏色、紋理坐標(biāo)儲存在一個VAO中崎淳。
shader改變一下堪夭，顏色從紋理中采樣
#version 330 core
in vec3 ourColor;
out vec4 color;
in vec2 TexCoord;
uniform sampler2D ourTexture;
void main()
{ color = texture(ourTexture, TexCoord);
}
texture函數(shù)傳入紋理對象和紋理坐標(biāo)，返回對應(yīng)點點顏色值拣凹！
glBindTexture(GL_TEXTURE_2D, texture);
glBindVertexArray(VAO);
glDrawArrays(GL_TRIANGLES, 0, 6);
glBindVertexArray(0);
當(dāng)只有一個紋理時森爽，不需要用glUniform像shader中傳值！
