I follow Nehe and GT Tutorials. While defining vertices, I’m getting a negative traingle which is cutting off the bottom of the sides of Cube. Why is it? Where I was wrong?
int DrawGLScene(GLvoid) // Here’s Where We Do All The Drawing
{
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); // Clear Screen And Depth Buffer
glLoadIdentity();
glTranslatef(1.5f,0.0f,-7.0f); // Move Right 3 Units
glRotatef(rquad,1.0f,1.0f,1.0f);
glBegin(GL_QUADS); // Draw A Cube
//Front Facing
glColor3f(1.0f, 1.0f, 0.0f);
glVertex3f(-1.0f, 1.0f, 1.0f); // Top Left
glVertex3f( 1.0f, 1.0f, 1.0f); // Top Right
glVertex3f( 1.0f,-1.0f, 1.0f); // Bottom Right
glVertex3f(-1.0f,-1.0f, 1.0f); // Bottom Left
//Right Facing
glColor3f(1.0f,0.0f,0.0f);
glVertex3f(1.0f,1.0f,1.0f); //Top Left
glVertex3f(1.0f,-1.0f,1.0f); //Bottom Left
glVertex3f(1.0f,1.0f,-1.0f); //Top Right
glVertex3f(1.0f,-1.0f,-1.0f); //Bottom Right
//Rear Facing
glColor3f(0.0f,1.0f,1.0f);
glVertex3f(1.0f,1.0f,-1.0f); //Top Left
glVertex3f(1.0f,-1.0f,-1.0f); //Bottom Left
glVertex3f(-1.0f,1.0f,-1.0f); //Top Right
glVertex3f(-1.0f,-1.0f,-1.0f); //Bottom Right
//Left Facing
glColor3f(1.0f,0.0f,1.0f);
glVertex3f(-1.0f,1.0f,-1.0f); //Top Left
glVertex3f(-1.0f,-1.0f,-1.0f); //Bottom Left
glVertex3f(-1.0f,1.0f,1.0f); //Top Right
glVertex3f(-1.0f,-1.0f,1.0f); //Bottom Right
//Top Facing
glColor3f(0.5f,0.0f,1.0f);
glVertex3f(-1.0f,1.0f,-1.0f); //Top Left
glVertex3f(1.0f,1.0f,-1.0f); //Top Right
glVertex3f(-1.0f,1.0f,1.0f); //Bottom Left
glVertex3f(1.0f,1.0f,1.0f);
//Bottom Facing
glColor3f(0.0f,0.5f,0.5f);
glVertex3f(-1.0f,-1.0f,1.0f); //Top Left
glVertex3f(1.0f,-1.0f,1.0f); //Top Right
glVertex3f(-1.0f,-1.0f,-1.0f); //Bottom Left
glVertex3f(1.0f,-1.0f,-1.0f); //Bottom Right
glEnd(); // Done Drawing The Quad
rquad-=0.03f;
return TRUE;
}