#include "Triangle.h"


Triangle::Triangle(float scale, float position)
: Model()
{
	mVertices[0][0]= -5.0f; mVertices[0][1]= 0.0f; mVertices[0][2]= 5.0f;
	mVertices[1][0]= 5.0f; mVertices[1][1]= 0.0f; mVertices[1][2]= 0.0f;
	mVertices[2][0]= 0.0f; mVertices[2][1]= 0.0f; mVertices[2][2]= -5.0f;
	mScaleFactor = scale;
	mYPosition = position;
	mFloorShadow = true;
}


Triangle::~Triangle(void)
{
}


void Triangle::draw()
{
	glColor3f(0.0f,0.0f,0.0f);
	glPushMatrix();
	glTranslatef(0.0f, mYPosition, 0.0f);
	glBegin( GL_TRIANGLES );
		//Want to avoid culling
		for ( int i = 0; i < 3; ++i )
		{
			glVertex3f(mVertices[i][0], mVertices[i][1], mVertices[i][2]);
		}
		for ( int i = 2; i > -1; --i )
		{
			glVertex3f(mVertices[i][0], mVertices[i][1], mVertices[i][2]);
		}
	glEnd();
	glPopMatrix();
}
void Triangle::draw_bottom()
{
	glColor3f(1.0f,1.0f,1.0f);
	glPushMatrix();
	glTranslatef(0.0f, mYPosition, 0.0f);
	glBegin(GL_TRIANGLES);
		for ( int i = 0; i < 3; ++i )
		{
			glVertex3f(mBottomVertices[i][0], mBottomVertices[i][1], mBottomVertices[i][2]);
		}
		for ( int i = 2; i > -1; --i )
		{
			glVertex3f(mBottomVertices[i][0], mBottomVertices[i][1], mBottomVertices[i][2]);
		}
	glEnd();
	glPopMatrix();
}

void Triangle::build_volume(GLfloat* light_pos, float* camera_pos)
{
	static float volume_size = 10.0f;  //Some big number that will for sure cover our needs
	//Initialize our bottom vertices to our top ones....
/*
	for ( int i = 0; i < 3; ++i )
		{
			mBottomVertices[i][0] = light_pos[0];
			mBottomVertices[i][1] = light_pos[1];
			mBottomVertices[i][2] = light_pos[2];
		}
	*/
	// Given out light point at L, and our three vertices: A,B,C
	// the direction vectors for our volume can be generated as following.
	// v1 = A - L.  This direction vector can then be scaled with out volume_size
	// maginute and added on to our initial A to give us out bottom vertice:
	// A' = A + volume_size * v1
	if (light_pos[1] > mYPosition)
	{
		mFloorShadow = true;
		for ( int i = 0; i < 3; ++i )
			{
				mBottomVertices[i][0] = light_pos[0] + (mVertices[i][0] - light_pos[0]) * volume_size;
				mBottomVertices[i][1] = light_pos[1] + (mVertices[i][1] - light_pos[1]) * volume_size;
				mBottomVertices[i][2] = light_pos[2]+ (mVertices[i][2] - light_pos[2]) * volume_size;
			}
	}
	else
	{
		mFloorShadow = false;
		for ( int i = 0; i < 3; ++i )
			{
				mBottomVertices[i][0] = light_pos[0] + (mVertices[i][0] + light_pos[0]) * volume_size;
				mBottomVertices[i][1] = light_pos[1] + (mVertices[i][1] + light_pos[1]) * volume_size;
				mBottomVertices[i][2] = light_pos[2] + (mVertices[i][2] + light_pos[2]) * volume_size;

			}
	}

}

void Triangle::draw_volume()
{

	//glEnable(GL_CULL_FACE);
	//glCullFace(GL_FRONT);

	glEnable (GL_BLEND); glBlendFunc (GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);


	glPushMatrix();
	glTranslatef(0.0f, mYPosition, 0.0f);
	//Draw top cap...
	glBegin( GL_TRIANGLES );
	glColor4f(0.0f,0.0f,0.0f,0.3f);
		for ( int i = 2; i > -1; --i )
		{
			glVertex3f(mVertices[i][0], mVertices[i][1], mVertices[i][2]);
		}
	glEnd();

	glColor4f(1.0f,1.0f,0.0f,0.3f);
		draw_quad(0,0,1,1);
	glColor4f(1.0f,0.0f,0.0f,0.3f);
		draw_quad(1,1,2,2);
	glColor4f(0.0f,1.0f,0.0f,0.3f);
		draw_quad(2,2,0,0);
	//Draw bottom cap...
	glBegin( GL_TRIANGLES );
	glColor4f(0.0f,0.0f,0.0f,0.3f);
		for ( int i = 0; i < 3; ++i )
		{
			glVertex3f(mBottomVertices[i][0], mBottomVertices[i][1], mBottomVertices[i][2]);
		}
	glEnd();

	glPopMatrix();


 	glDisable (GL_BLEND);

	//glDisable(GL_CULL_FACE);



}

void Triangle::draw_quad(int first_top, int second_bottom, int third_bottom, int fourth_top)
{
	/*cout << "Drawing quad from: ("<<mVertices[first_top][0]<<","<<mVertices[first_top][1]<<","<<mVertices[first_top][2]<<"), "
		<< "("<<mBottomVertices[second_bottom][0]<<","<<mBottomVertices[second_bottom][1]<<","<<mBottomVertices[second_bottom][2]<<"), "
		<< "("<<mBottomVertices[third_bottom][0]<<","<<mBottomVertices[third_bottom][1]<<","<<mBottomVertices[third_bottom][2]<<"), "
		<< "("<<mVertices[fourth_top][0]<<","<<mVertices[fourth_top][1]<<","<<mVertices[fourth_top][2]<<"), " << endl;*/
	if (mFloorShadow)
	{
		glBegin(GL_QUADS);
				glVertex3f(mVertices[first_top][0], mVertices[first_top][1], mVertices[first_top][2]);
				glVertex3f(mBottomVertices[second_bottom][0], mBottomVertices[second_bottom][1],mBottomVertices[second_bottom][2]);
				glVertex3f(mBottomVertices[third_bottom][0], mBottomVertices[third_bottom][1],mBottomVertices[third_bottom][2]);
				glVertex3f(mVertices[fourth_top][0], mVertices[fourth_top][1], mVertices[fourth_top][2]);
			glEnd();
	}
	else
		//Reverse order to fix culling
	{
		glBegin(GL_QUADS);
				glVertex3f(mVertices[first_top][0], mVertices[first_top][1], mVertices[first_top][2]);
				glVertex3f(mVertices[fourth_top][0], mVertices[fourth_top][1], mVertices[fourth_top][2]);
				glVertex3f(mBottomVertices[third_bottom][0], mBottomVertices[third_bottom][1],mBottomVertices[third_bottom][2]);
				glVertex3f(mBottomVertices[second_bottom][0], mBottomVertices[second_bottom][1],mBottomVertices[second_bottom][2]);
			glEnd();
	}
}