Lighting not working in opengl [closed] - c

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I am having trouble getting the lighting to work on just the decline portion of my ground. Below is my code for the ground and the decline (making it a ditch):
static void ground(double x, double y, double z, double dx, double dy,
double dz){
float white[] = {1,1,1,1};
float Emission[] = {0.0,0.0,0.01*emission,1.0};
glMaterialf(GL_FRONT_AND_BACK,GL_SHININESS,shiny);
glMaterialfv(GL_FRONT_AND_BACK,GL_SPECULAR,white);
glMaterialfv(GL_FRONT_AND_BACK,GL_EMISSION,Emission);
// Save transformation
glPushMatrix();
// Offset, scale and rotate
glTranslated(x,y,z);
glScaled(dx, dy, dz);
glEnable(GL_TEXTURE_2D);
glTexEnvi(GL_TEXTURE_ENV,GL_TEXTURE_ENV_MODE,GL_MODULATE);
glBindTexture(GL_TEXTURE_2D, textures[2]);
glBegin(GL_QUADS);
glColor3f(0.5, 1.0, 0.5);
glNormal3f(0,0,0);
glTexCoord2f(0.0, 0.0); glVertex3f(-100, 0, -300);
glTexCoord2f(300.0,0.0); glVertex3f(-100,0,300);
glTexCoord2f(300.0,300.0); glVertex3f(-3,0,300);
glTexCoord2f(0.0,300.0); glVertex3f(-3,0,-300);
glEnd();
glBindTexture(GL_TEXTURE_2D, textures[2]);
glBegin(GL_QUADS);
glColor3f(1.0, 1.0, 0.5);
glNormal3f(0,0,-1);
glTexCoord2f(0.0, 0.0); glVertex3f(-2.99,0,-300);
glTexCoord2f(300.0,0.0); glVertex3f(-2.99,0,300);
glTexCoord2f(300.0,300.0); glVertex3f(-1,-1,300);
glTexCoord2f(0.0,300.0); glVertex3f(-1,-1,-300);
glEnd();
glBindTexture(GL_TEXTURE_2D, textures[2]);
glBegin(GL_QUADS);
glColor3f(1.0, 1.0, 0.5);
glNormal3f(0,0,1);
glTexCoord2f(0.0, 0.0); glVertex3f(0.99,-1,-300);
glTexCoord2f(300.0,0.0); glVertex3f(0.99,-1,300);
glTexCoord2f(300.0,300.0); glVertex3f(2.99,0,300);
glTexCoord2f(0.0,300.0); glVertex3f(2.99,0,-300);
glEnd();
glBindTexture(GL_TEXTURE_2D, textures[2]);
glBegin(GL_QUADS);
glColor3f(0.5, 1.0, 0.5);
glNormal3f(0,0,0);
glTexCoord2f(0.0, 0.0); glVertex3f(2.99, 0, -300);
glTexCoord2f(300.0,0.0); glVertex3f(2.99,0,300);
glTexCoord2f(300.0,300.0); glVertex3f(100,0,300);
glTexCoord2f(0.0,300.0); glVertex3f(100,0,-300);
glEnd();
glPopMatrix();
glDisable(GL_TEXTURE_2D);
}
So the code the doesn't have lighting working correctly is the middle two snippets of "glBegin(GL_QUADS)"

Answer 1

This is just an instance of GIGO (garbage in, garbage out):
glNormal3f(0,0,0);
Nope. That is not a valid normal vector, and will totally break any lighting calculation.
The next one
glNormal3f(0,0,-1);
glTexCoord2f(0.0, 0.0); glVertex3f(-2.99,0,-300);
glTexCoord2f(300.0,0.0); glVertex3f(-2.99,0,300);
glTexCoord2f(300.0,300.0); glVertex3f(-1,-1,300);
glTexCoord2f(0.0,300.0); glVertex3f(-1,-1,-300);
is at least some non-null vector, but it isn't normal to the face you are describing, so the lighting will be just wrong.