#include "stdafx.h"


GLfloat colors[][3] = { {0.0,0.0,0.0},{1.0,0.0,0.0},
{1.0,1.0,0.0}, {0.0,1.0,0.0}, {0.0,0.0,1.0},
{1.0,0.0,1.0}, {1.0,1.0,1.0}, {0.0,1.0,1.0} };

#define GL_PI 3.1415f

GLfloat xRot = 0.45f;
GLfloat yRot = 0.35f;
GLboolean bCull = glIsEnabled(GL_CULL_FACE);
GLboolean bDepth = glIsEnabled(GL_DEPTH_TEST);
GLboolean bOutline = (GLboolean)true;

GLenum shademode = GL_FLAT;

GLfloat ex = 0.0f;
GLfloat ey = 0.0f;
GLfloat ez = -120.0f;
GLfloat delta = 0.01f;
GLfloat deltaR = 0.01f;

GLfloat pos_luz[4] = { 0., 25., 0, 1. };
GLfloat piso[4] = { 0. , 1., 0., /*-25.*/25 };
GLfloat MatrizSombra[16];

void cuadrado() {
	glBegin(GL_QUADS);
	glVertex2f(1., 1.);
	glVertex2f(-1., 1.);
	glVertex2f(-1., -1.);
	glVertex2f(1., -1.);
	glEnd();

}

void colorcube1_sin_color() {
	/* cara 1 */

	glPushMatrix();
	glTranslatef(0., 0., 1.);
	cuadrado();
	glPopMatrix();

	/* cara 2 */

	glPushMatrix();
	glRotatef(90., 0., 1., 0.);
	glTranslatef(0., 0., 1.);
	cuadrado();
	glPopMatrix();

	/* cara 3 */

	glPushMatrix();
	glRotatef(180., 0., 1., 0.);
	glTranslatef(0., 0., 1.);
	cuadrado();
	glPopMatrix();

	/* cara 4 */

	glPushMatrix();
	glRotatef(-90., 0., 1., 0.);
	glTranslatef(0., 0., 1.);
	cuadrado();
	glPopMatrix();


	/* cara 5 */

	glPushMatrix();
	glRotatef(90., 0., 0., 1.);
	glRotatef(-90., 0., 1., 0.);
	glTranslatef(0., 0., 1.);
	cuadrado();
	glPopMatrix();

	/* cara 6 */

	glPushMatrix();
	glRotatef(-90., 0., 0., 1.);
	glRotatef(-90., 0., 1., 0.);
	glTranslatef(0., 0., 1.);
	cuadrado();
	glPopMatrix();
}

void colorcube1(void)
{

	/* cara 1 */
	glColor3fv(colors[1]);
	glPushMatrix();
	glTranslatef(0., 0., 1.);
	cuadrado();
	glPopMatrix();

	/* cara 2 */
	glColor3fv(colors[3]);
	glPushMatrix();
	glRotatef(90., 0., 1., 0.);
	glTranslatef(0., 0., 1.);
	cuadrado();
	glPopMatrix();

	/* cara 3 */
	glColor3fv(colors[2]);
	glPushMatrix();
	glRotatef(180., 0., 1., 0.);
	glTranslatef(0., 0., 1.);
	cuadrado();
	glPopMatrix();

	/* cara 4 */
	glColor3fv(colors[7]);
	glPushMatrix();
	glRotatef(-90., 0., 1., 0.);
	glTranslatef(0., 0., 1.);
	cuadrado();
	glPopMatrix();


	/* cara 5 */
	glColor3fv(colors[6]);
	glPushMatrix();
	glRotatef(90., 0., 0., 1.);
	glRotatef(-90., 0., 1., 0.);
	glTranslatef(0., 0., 1.);
	cuadrado();
	glPopMatrix();

	/* cara 6 */
	glColor3fv(colors[5]);
	glPushMatrix();
	glRotatef(-90., 0., 0., 1.);
	glRotatef(-90., 0., 1., 0.);
	glTranslatef(0., 0., 1.);
	cuadrado();
	glPopMatrix();
}




void gltMakeShadowMatrix(GLfloat vPlaneEquation[], GLfloat vLightPos[], GLfloat destMat[])
{
	GLfloat dot;

	// Dot product of plane and light position
	dot = vPlaneEquation[0] * vLightPos[0] + vPlaneEquation[1] * vLightPos[1] +
		vPlaneEquation[2] * vLightPos[2] + vPlaneEquation[3] * vLightPos[3];

	// Now do the projection
	// First column
	destMat[0] = dot - vLightPos[0] * vPlaneEquation[0];
	destMat[4] = 0.0f - vLightPos[0] * vPlaneEquation[1];
	destMat[8] = 0.0f - vLightPos[0] * vPlaneEquation[2];
	destMat[12] = 0.0f - vLightPos[0] * vPlaneEquation[3];

	// Second column
	destMat[1] = 0.0f - vLightPos[1] * vPlaneEquation[0];
	destMat[5] = dot - vLightPos[1] * vPlaneEquation[1];
	destMat[9] = 0.0f - vLightPos[1] * vPlaneEquation[2];
	destMat[13] = 0.0f - vLightPos[1] * vPlaneEquation[3];

	// Third Column
	destMat[2] = 0.0f - vLightPos[2] * vPlaneEquation[0];
	destMat[6] = 0.0f - vLightPos[2] * vPlaneEquation[1];
	destMat[10] = dot - vLightPos[2] * vPlaneEquation[2];
	destMat[14] = 0.0f - vLightPos[2] * vPlaneEquation[3];

	// Fourth Column
	destMat[3] = 0.0f - vLightPos[3] * vPlaneEquation[0];
	destMat[7] = 0.0f - vLightPos[3] * vPlaneEquation[1];
	destMat[11] = 0.0f - vLightPos[3] * vPlaneEquation[2];
	destMat[15] = dot - vLightPos[3] * vPlaneEquation[3];
}

void SetupRC()
{
	// Black background
	glClearColor(0.0f, 0.0f, 0.0f, 1.0f);

	// Set drawing color to green
	glColor3f(0.0f, 1.0f, 0.0f);

	// Set color shading model to flat
	glShadeModel(shademode);

	// Clockwise-wound polygons are front facing; this is reversed
	// because we are using triangle fans
	glFrontFace(GL_CW);
}

void foco()
{
	glPushMatrix();
	glTranslatef(pos_luz[0]/*0.*/, pos_luz[1] /*25.*/, pos_luz[2] /*0.*/);
	glColor3f(1.f, 1.f, 0.);
	glutSolidSphere(1., 20, 20);
	glPopMatrix();
}

void Piso() {
	glPushMatrix();
	glTranslatef(0., -piso[3]/*-25.*/, 0.);
	glRotatef(90., 1., 0., 0.);
	glScalef(40., 40., 40.);
	glColor3f(0.8f, 0.8f, 0.8f);
	cuadrado();
	glPopMatrix();
}

void Objetos()
{
	glPushMatrix();
	glScalef(10., 10., 10.);
	colorcube1();
	glPopMatrix();
}

void Objetos_sin_color()
{
	glPushMatrix();
	glScalef(10., 10., 10.);
	colorcube1_sin_color();//colorcube1();
	glPopMatrix();
}

void SombradeMiMundo(GLfloat datosdeLuz[], GLfloat datosdePlano[]) {

	glColor3f(0.4, 0.4, 0.4);
	glPushMatrix();
	gltMakeShadowMatrix(datosdePlano, datosdeLuz, MatrizSombra);
	glMultMatrixf(MatrizSombra);
	Objetos_sin_color();
	glPopMatrix();
}


// Called to draw scene

void RenderScene(void)
{
	// Reset coordinate system

	glLoadIdentity();
	gluLookAt(ex, ey, ez, 0.0, 0.0, 0.0, 0.0, 1.0, 0.0);

	GLfloat x, y, angle;         // Storage for coordinates and angles
	int iPivot = 1;            // Used to flag alternating colors

	// Clear the window and the depth buffer
	glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

	// Turn culling on if flag is set
	if (bCull)   glEnable(GL_CULL_FACE);
	else        glDisable(GL_CULL_FACE);

	// Enable depth testing if flag is set
	if (bDepth)  glEnable(GL_DEPTH_TEST);
	else        glDisable(GL_DEPTH_TEST);

	// Draw the back side as a wireframe only, if flag is set
	if (bOutline)glPolygonMode(GL_BACK, GL_LINE);
	else        glPolygonMode(GL_BACK, GL_FILL);

	// Save matrix state and do the rotation
	glPushMatrix();
	glRotatef(xRot, 1.0f, 0.0f, 0.0f);
	glRotatef(yRot, 0.0f, 1.0f, 0.0f);

	/*mundo virtual*/


	/*foco*/
	foco();

	/*piso*/
	Piso();

	SombradeMiMundo(/*GLfloat datosdeLuz[]*/pos_luz, /*GLfloat datosdePlano[]*/piso);

	/*cubo*/
	Objetos();

	glPopMatrix();

	// Flush drawing commands
	glutSwapBuffers();
}

// Called by GLUT library when the window has changed size

void ChangeSize(GLsizei w, GLsizei h)
{    // Set Viewport to window dimensions
	glViewport(0, 0, (GLsizei)w, (GLsizei)h);

	glMatrixMode(GL_PROJECTION);
	glLoadIdentity();

	//glOrtho (-100.0, 100.0, -100, 100, -270.0, 270.0);
	//glFrustum (-1.0, 1.0, -1.0, 1.0, 1.5, 20.0);
	gluPerspective(60.0, 1.0, 1.5, 500.0);
	glMatrixMode(GL_MODELVIEW);
}



void SpecialKeys(int key, int x, int y)
{
	GLfloat dx, dz;


	if (key == GLUT_KEY_UP)
	{//increase distance from camera to origin
		ex *= (1.0f + deltaR);  ey *= (1.0f + deltaR);    ez *= (1.0f + deltaR);
	}

	if (key == GLUT_KEY_DOWN)
	{//reduce distance from camera to origin (close up)
		ex *= (1.0f - deltaR); ey *= (1.0f - deltaR);    ez *= (1.0f - deltaR);
	}

	if (key == GLUT_KEY_LEFT)
		//Rotate camera around origin in Oxz plane
	{
		dx = -ez;     dz = ex;
		GLfloat s = sqrtf(ex*ex + ey * ey + ez * ez);
		ex += delta * dx;       ez += delta * dz;
		GLfloat s1 = sqrtf(ex*ex + ey * ey + ez * ez) / s;
		ex /= s1;    ey /= s1;    ey /= s1;
	}

	if (key == GLUT_KEY_RIGHT)
		//Rotate camera around origin in Oxz plane
	{
		dx = -ez;     dz = ex;
		GLfloat s = sqrtf(ex*ex + ey * ey + ez * ez);
		ex -= delta * dx;          ez -= delta * dz;
		GLfloat s1 = sqrtf(ex*ex + ey * ey + ez * ez) / s;
		ex /= s1;    ey /= s1;    ey /= s1;
	}


	if (key == GLUT_KEY_F1) bCull = !bCull;
	if (key == GLUT_KEY_F2)bDepth = !bDepth;
	if (key == GLUT_KEY_F3)bOutline = !bOutline;
	if (key == GLUT_KEY_F4)
	{
		if (shademode == GL_FLAT) { shademode = GL_SMOOTH; }
		else { if (shademode == GL_SMOOTH) { shademode = GL_FLAT; } };
		glShadeModel(shademode);
	}

	if (key == GLUT_KEY_F7) pos_luz[1] *= (1. + delta);
	if (key == GLUT_KEY_F8) pos_luz[1] *= (1. - delta);
	// Refresh the Window
	glutPostRedisplay();


	// Refresh the Window
	glutPostRedisplay();
}


///////////////////////////////////////////////////////////



int main(int argc, char** argv)
{
	glutInit(&argc, argv);
	glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGB);
	glutInitWindowSize(200, 200);
	glutInitWindowPosition(100, 100);
	glutCreateWindow(argv[0]);
	glutDisplayFunc(RenderScene);
	glutReshapeFunc(ChangeSize);
	glutSpecialFunc(SpecialKeys);

	SetupRC();
	glutMainLoop();
	return 0;
}