static const float p_vertex[12] = {-0.5,0.5,0.0, -0.5,-0.5,0.0, 0.5,-0.5,0.0, 0.5,0.5,0.0};static const short p_index[6] = {0,1,2, 0,2,3};static ssShader*    g_shader = 0;static GLuint        g_vao = 9999;static GLuint        g_vbo[3];{//glDrawArrays    //vao    glGenVertexArrays(1, &g_vao);    glBindVertexArray(g_vao);    //vbo    glGenBuffers(1, &g_vbo[0]);      glBindBuffer(GL_ARRAY_BUFFER, g_vbo[0]);    glBufferData(GL_ARRAY_BUFFER, sizeof(float)*12, p_vertex, GL_STATIC_DRAW);    //绑定vbo到vao    glEnableVertexAttribArray(0);    //glBindBuffer(GL_ARRAY_BUFFER, g_vbo[0]);    glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 0, 0);    glBindVertexArray(0);      glBindBuffer(GL_ARRAY_BUFFER, 0);    glBindVertexArray(g_vao);    glDrawArrays(GL_TRIANGLES, 0, 3);    glBindVertexArray(0);}{//glDrawElements    //vao    glGenVertexArrays(1, &g_vao);    glBindVertexArray(g_vao);    //vbo    glGenBuffers(1, &g_vbo[0]);     glBindBuffer(GL_ARRAY_BUFFER, g_vbo[0]);    glBufferData(GL_ARRAY_BUFFER, sizeof(float)*12, p_vertex, GL_STATIC_DRAW);    glGenBuffers(1, &g_vbo[1]);    glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, g_vbo[1]);    glBufferData(GL_ELEMENT_ARRAY_BUFFER, sizeof(short)*6, p_index, GL_STATIC_DRAW);    //绑定vbo到vao    glEnableVertexAttribArray(0);    glBindBuffer(GL_ARRAY_BUFFER, g_vbo[0]);    glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 0, 0);    glBindVertexArray(0);     glBindBuffer(GL_ARRAY_BUFFER, 0);    glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);    glBindVertexArray(g_vao);    //glDrawArrays(GL_TRIANGLES, 0, 3);    glDrawElements(GL_TRIANGLES, 6, GL_UNSIGNED_SHORT, 0);    glBindVertexArray(0);}必须先调用glBindVertexArray(0)再调用glBindBuffer(GL_ARRAY_BUFFER, 0)