android - OpenGL FRONT_AND_BACK

Question

我使用以下方法剔除我的对象:

fx.g.glEnable(GL10.GL_CULL_FACE);
fx.g.glCullFace(GL10.GL_BACK);

然而，当我为我的对象设置蓝色 Material 时，它们显示为灰色:

fx.g.glMaterialfv(GL10.GL_BACK, GL10.GL_AMBIENT, ambient, 0);
fx.g.glMaterialfv(GL10.GL_BACK, GL10.GL_DIFFUSE, diffuse, 0);
fx.g.glMaterialfv(GL10.GL_BACK, GL10.GL_SPECULAR, specular, 0);
fx.g.glMaterialfv(GL10.GL_BACK, GL10.GL_SHININESS, Ns, 0);

和

fx.g.glMaterialfv(GL10.GL_FRONT, GL10.GL_AMBIENT, ambient, 0);
fx.g.glMaterialfv(GL10.GL_FRONT, GL10.GL_DIFFUSE, diffuse, 0);
fx.g.glMaterialfv(GL10.GL_FRONT, GL10.GL_SPECULAR, specular, 0);
fx.g.glMaterialfv(GL10.GL_FRONT, GL10.GL_SHININESS, Ns, 0);

但是蓝色的

fx.g.glMaterialfv(GL10.GL_FRONT_AND_BACK, GL10.GL_AMBIENT, ambient, 0);
fx.g.glMaterialfv(GL10.GL_FRONT_AND_BACK, GL10.GL_DIFFUSE, diffuse, 0);
fx.g.glMaterialfv(GL10.GL_FRONT_AND_BACK, GL10.GL_SPECULAR, specular, 0);
fx.g.glMaterialfv(GL10.GL_FRONT_AND_BACK, GL10.GL_SHININESS, Ns, 0);

环境光/漫反射/镜面反射和 ns 具有相同的值。

知道为什么会这样吗？似乎 GL_FRONT 和 GL_BACK Material 都被完全忽略了，但是 GL_FRONT_AND_BACK 工作得很好，不确定它们是否是使用它的性能问题，或者这是否意味着我在其他地方有错误!

Answer 1

it seems both GL_FRONT and GL_BACK materials are completely ignored

Working as intended :

face: Specifies which face or faces are being updated. Must be GL_FRONT_AND_BACK.