Accordingly, if you want to map the lower left corner (-1, -1) of the cube's front face to the texture's lower left corner, you must assign the texture coordinates (0, 1) to vertex 0.
相应地,如果您需要将立方体正面的左下角映射到纹理的左下角,必须将纹理坐标(0,1)指派给顶点0。
2
For a triangle in a given 3-d mesh, the order in which the triangle's vertex positions are specified determines whether the triangle face is a front or back face.