OpenGL lighting problems

**sirSolarius** · 12-01-2003

I really don't understand lighting in OpenGL... I set up the following:

Code:

//////////////////////////////////////////////////////////////////
//////               *LIGHTING*             //////////////////////
///////////////////////////////////////////////////////////////////
GLfloat lightAmbient[]=		{ 1.0f, 1.0f, 1.0f, 1.0f };
GLfloat specularLight[]=	{ 1.0f, 1.0f, 1.0f, 1.0f };
GLfloat diffuseLight[]=		{ 1.0f, 1.0f, 1.0f, 1.0f };
GLfloat LightPosition[]=	{ 0.0f, 3.0f, -2.0f, 1.0f };
///////////////////////////////////////////////////////////////////

And then in initialization:

Code:

glEnable(GL_TEXTURE_2D);							// Enable Texture Mapping
	glShadeModel(GL_SMOOTH);							// Enable Smooth Shading
	glClearColor(0.0f, 0.0f, 0.0f, 0.5f);				// Black Background
	glClearDepth(1.0f);									// Depth Buffer Setup
	glEnable(GL_DEPTH_TEST);							// Enables Depth Testing
	glDepthFunc(GL_LEQUAL);								// The Type Of Depth Testing To Do
    glEnable(GL_CULL_FACE);								// Enable culling.
    glFrontFace(GL_CCW);								// Enable counter clockwise culling.
    glEnable(GL_LIGHTING);							    // Enable lighting.
	glHint(GL_PERSPECTIVE_CORRECTION_HINT, GL_NICEST);	// Really Nice Perspective Calculations
	
	glPolygonMode(GL_FRONT_AND_BACK, GL_FILL);
	
	///////////Lights//////////////////////////////
	glLightfv(GL_LIGHT0, GL_DIFFUSE, diffuseLight);
    glLightfv(GL_LIGHT0, GL_SPECULAR, specularLight);
	glLightfv(GL_LIGHT0, GL_AMBIENT, lightAmbient);
    glLightfv(GL_LIGHT0, GL_POSITION, LightPosition);
    glEnable(GL_LIGHT0);
   ///////////////////////////////////////////////
   
   ///////////COLOR MATERIAL//////////////////////
   glEnable(GL_COLOR_MATERIAL);

   glColorMaterial(GL_FRONT, GL_AMBIENT_AND_DIFFUSE);
   glMaterialfv(GL_FRONT, GL_SPECULAR, specularLight);
   glMateriali(GL_FRONT, GL_SHININESS, 128);
   glColorMaterial(GL_BACK, GL_AMBIENT_AND_DIFFUSE);
   glMaterialfv(GL_BACK, GL_SPECULAR, specularLight);
   glMateriali(GL_BACK, GL_SHININESS, 128);
   ///////////////////////////////////////////////

The problem is that when I draw a box

Code:

void Box::draw()
{
	glRotatef(getRotX(), 1.0f, 0.0f, 0.0f);
	glRotatef(getRotY(), 0.0f, 1.0f, 0.0f);
	glRotatef(getRotZ(), 0.0f, 0.0f, 1.0f);

	glTranslatef(getX(), getY(), getZ());
	
	glColor3f(getRed(), getGreen(), getBlue());

	glBegin(GL_QUADS);
		// Front Face
		glNormal3f( 0.0f, 0.0f, getLength());
		//glTexCoord2f(0.0f, 0.0f);
		glVertex3f(-getHeight(), -getWidth(),  getLength());
		//glTexCoord2f(1.0f, 0.0f); 
		glVertex3f( getHeight(), -getWidth(),  getLength());
		//glTexCoord2f(1.0f, 1.0f); 
		glVertex3f( getHeight(),  getWidth(),  getLength());
		//glTexCoord2f(0.0f, 1.0f); 
		glVertex3f(-getHeight(),  getWidth(),  getLength());
		// Back Face
		glNormal3f( 0.0f, 0.0f,-getLength());
		//glTexCoord2f(1.0f, 0.0f); 
		glVertex3f(-getHeight(), -getWidth(), -getLength());
		//glTexCoord2f(1.0f, 1.0f); 
		glVertex3f(-getHeight(),  getWidth(), -getLength());
		//glTexCoord2f(0.0f, 1.0f); 
		glVertex3f( getHeight(),  getWidth(), -getLength());
		//glTexCoord2f(0.0f, 0.0f); 
		glVertex3f( getHeight(), -getWidth(), -getLength());
		// Top Face
		glNormal3f( 0.0f, getLength(), 0.0f);
		//glTexCoord2f(0.0f, 1.0f); 
		glVertex3f(-getHeight(),  getWidth(), -getLength());
		//glTexCoord2f(0.0f, 0.0f); 
		glVertex3f(-getHeight(),  getWidth(),  getLength());
		//glTexCoord2f(1.0f, 0.0f); 
		glVertex3f( getHeight(),  getWidth(),  getLength());
		//glTexCoord2f(1.0f, 1.0f); 
		glVertex3f( getHeight(),  getWidth(), -getLength());
		// Bottom Face
		glNormal3f( 0.0f,-getLength(), 0.0f);
		//glTexCoord2f(1.0f, 1.0f); 
		glVertex3f(-getHeight(), -getWidth(), -getLength());
		//glTexCoord2f(0.0f, 1.0f); 
		glVertex3f( getHeight(), -getWidth(), -getLength());
		//glTexCoord2f(0.0f, 0.0f); 
		glVertex3f( getHeight(), -getWidth(),  getLength());
		//glTexCoord2f(1.0f, 0.0f); 
		glVertex3f(-getHeight(), -getWidth(),  getLength());
		// Right face
		glNormal3f( getLength(), 0.0f, 0.0f);
		//glTexCoord2f(1.0f, 0.0f); 
		glVertex3f( getHeight(), -getWidth(), -getLength());
		//glTexCoord2f(1.0f, 1.0f); 
		glVertex3f( getHeight(),  getWidth(), -getLength());
		//glTexCoord2f(0.0f, 1.0f); 
		glVertex3f( getHeight(),  getWidth(),  getLength());
		//glTexCoord2f(0.0f, 0.0f); 
		glVertex3f( getHeight(), -getWidth(),  getLength());
		// Left Face
		glNormal3f(-getLength(), 0.0f, 0.0f);
		//glTexCoord2f(0.0f, 0.0f); 
		glVertex3f(-getHeight(), -getWidth(), -getLength());
		//glTexCoord2f(1.0f, 0.0f); 
		glVertex3f(-getHeight(), -getWidth(),  getLength());
		//glTexCoord2f(1.0f, 1.0f); 
		glVertex3f(-getHeight(),  getWidth(),  getLength());
		//glTexCoord2f(0.0f, 1.0f); 
		glVertex3f(-getHeight(),  getWidth(), -getLength());
	glEnd();

It just appears brown, although shaded and despite the fact that the boxes are given different colors.

My scene drawing code goes here:

Code:

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();									// Reset The Current Modelview Matrix
	glColor3f(1.0f,1.0f,1.0f);							// Set The Color To White
	
	(*currentCam).draw();
	glBindTexture(GL_TEXTURE_2D, texture[2]);		// Map Texture to the Box

	// Draw the Room ie Crate
	glBegin(GL_QUADS);
		// Front Face
		glNormal3f( 0.0f, 0.0f, 9.0f);
		glTexCoord2f(0.0f, 0.0f); glVertex3f(-9.0f, -5.0f,  9.0f);
		glTexCoord2f(1.0f, 0.0f); glVertex3f( 9.0f, -5.0f,  9.0f);
		glTexCoord2f(1.0f, 1.0f); glVertex3f( 9.0f,  5.0f,  9.0f);
		glTexCoord2f(0.0f, 1.0f); glVertex3f(-9.0f,  5.0f,  9.0f);
		// Back Face
		glNormal3f( 0.0f, 0.0f,-9.0f);
		glTexCoord2f(1.0f, 0.0f); glVertex3f(-9.0f, -5.0f, -9.0f);
		glTexCoord2f(1.0f, 1.0f); glVertex3f(-9.0f,  5.0f, -9.0f);
		glTexCoord2f(0.0f, 1.0f); glVertex3f( 9.0f,  5.0f, -9.0f);
		glTexCoord2f(0.0f, 0.0f); glVertex3f( 9.0f, -5.0f, -9.0f);
		// Top Face
		glNormal3f( 0.0f, 9.0f, 0.0f);
		glTexCoord2f(0.0f, 1.0f); glVertex3f(-9.0f,  5.0f, -9.0f);
		glTexCoord2f(0.0f, 0.0f); glVertex3f(-9.0f,  5.0f,  9.0f);
		glTexCoord2f(1.0f, 0.0f); glVertex3f( 9.0f,  5.0f,  9.0f);
		glTexCoord2f(1.0f, 1.0f); glVertex3f( 9.0f,  5.0f, -9.0f);
		// Bottom Face
		glNormal3f( 0.0f,-9.0f, 0.0f);
		glTexCoord2f(1.0f, 1.0f); glVertex3f(-9.0f, -5.0f, -9.0f);
		glTexCoord2f(0.0f, 1.0f); glVertex3f( 9.0f, -5.0f, -9.0f);
		glTexCoord2f(0.0f, 0.0f); glVertex3f( 9.0f, -5.0f,  9.0f);
		glTexCoord2f(1.0f, 0.0f); glVertex3f(-9.0f, -5.0f,  9.0f);
		// Right face
		glNormal3f( 9.0f, 0.0f, 0.0f);
		glTexCoord2f(1.0f, 0.0f); glVertex3f( 9.0f, -5.0f, -9.0f);
		glTexCoord2f(1.0f, 1.0f); glVertex3f( 9.0f,  5.0f, -9.0f);
		glTexCoord2f(0.0f, 1.0f); glVertex3f( 9.0f,  5.0f,  9.0f);
		glTexCoord2f(0.0f, 0.0f); glVertex3f( 9.0f, -5.0f,  9.0f);
		// Left Face
		glNormal3f(-9.0f, 0.0f, 0.0f);
		glTexCoord2f(0.0f, 0.0f); glVertex3f(-9.0f, -5.0f, -9.0f);
		glTexCoord2f(1.0f, 0.0f); glVertex3f(-9.0f, -5.0f,  9.0f);
		glTexCoord2f(1.0f, 1.0f); glVertex3f(-9.0f,  5.0f,  9.0f);
		glTexCoord2f(0.0f, 1.0f); glVertex3f(-9.0f,  5.0f, -9.0f);
	glEnd();

	glLoadIdentity();
	
	lister.drawObjects(currentCam);  //so far just calling the box code above for multiple objects

Finally, the drawObjects method:

Code:

void ObjectList::drawObjects(Camera *cam)
{
	Object* current=head;
	while(current !=NULL)
	{
		glLoadIdentity();
		(*cam).draw();
		(*current).draw();
		current=(*current).getNext();
	}
}

The problems are the following:
-All the boxes appear brown
-The inside of the room ie crate are pitch black, but the outside is textured and lit

Thanks, and sorry for all the code, but it's better to have it and not need it, right?

OpenGL lighting problems

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