使用纹理时内存泄漏

我画了界面。有些元素有纹理。每次更新时，占用的内存量都会增加。这就是在元素上绘制纹理的代码的样子。

void RecordLabel::Draw() {
    glEnableClientState(GL_VERTEX_ARRAY);
    glEnable(GL_BLEND);
    GLuint      tex;

    glGenTextures(1, &tex);
    glBindTexture(GL_TEXTURE_2D, tex);

    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);

    int w1 = image.GetWidth(), h1 = image.GetHeight();
    int glw1 = NextPow2(w1), glh1 = NextPow2(h1);

    unsigned char *d = image.GetData();
    unsigned char *a = image.GetAlpha();
    unsigned char *e = new unsigned char[4 * w1 * h1];

    if (d && e && a){
        for (int p = 0; p < w1*h1; p++) {
            e[4 * p + 0] = d[3 * p + 0];
            e[4 * p + 1] = d[3 * p + 1];
            e[4 * p + 2] = d[3 * p + 2];
            e[4 * p + 3] = a[p];
        }
    }
    glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA,
        glw1, glh1, 0, GL_RGBA, GL_UNSIGNED_BYTE, 0);

    glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0,
        w1, h1, GL_RGBA, GL_UNSIGNED_BYTE, e);


    delete[] e;

    glEnable(GL_TEXTURE_2D);

    glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_REPLACE);

    float glw = image.GetWidth(), glh = image.GetHeight();
    float ut = 1, v = 1;
    float wt = w, ht = h;


    glBegin(GL_QUADS);
    glTexCoord2f(0, v), glVertex2f(cx - w / 2, cy + h / 2);
    glTexCoord2f(ut, v), glVertex2f(cx + w / 2, cy + h / 2);
    glTexCoord2f(ut, 0), glVertex2f(cx + w / 2, cy - h / 2);
    glTexCoord2f(0, 0), glVertex2f(cx - w / 2, cy - h / 2);
    glEnd();
    glDisable(GL_TEXTURE_2D);

    glDisableClientState(GL_VERTEX_ARRAY);
    glDisable(GL_BLEND);

}