#include "stdafx.h"
#include <Windows.h>
#include "include\GL\GL.H"
#include "include\GL\GLU.H"
#include "include\GL\glut.h"
#include <cmath>


// position of first triangle for all of colors
float blueT[3][2] = { {0.0,0.0}, {50.0,0.0}, {0.0, 50.0} };
float greenT[3][2] = { {50.0,0.0}, {100.0,0.0}, {50.0, -50.0} };
float orangeT[3][2] = { {50.0,0.0}, {100.0,0.0}, {50.0, 50.0} };
float pinkT[3][2] = { {100.0,0.0}, {150.0,0.0}, {100.0, 50.0} };
float yellowT[3][2] = { {50.0,50.0}, {50.0,100.0}, {100.0, 50.0} };
float redT[3][2] = { {100.0,0.0}, {150.0,0.0}, {100.0, -50.0} };

int i = 0;

GLfloat angleX = 0.0;
float shiftX = 0;
float shiftY = 0;
float shift = 1;

void setColor(int color) {
	switch (color)
	{
	case 1:
		glColor4f(0.0f, 0.0f, 1.0f, 1.0f); //blue
		break;
	case 2:
		glColor4f(1.0f, 0.0f, 0.0f, 1.0f); //red
		break;
	case 3:
		glColor4f(0.0f, 1.0f, 0.0f, 1.0f); //green
		break;

	case 4:
		glColor4f(1.0f, 1.0f, 0.0f, 1.0f); //yellow
		break;

	case 5:
		glColor4f(1.0f, 0.0f, 1.0f, 1.0f); //pink
		break;

	case 6:
		glColor4f(1.0f, 0.65f, 0.0f, 1.0f); //orange
		break;
	}
}

void timer(int value) {
	angleX -= shift;
	if (angleX < -360) {
		angleX = 0;
		shiftX = 0;
		shiftY = 0;
	}
	if (angleX >= -180) {
		shiftX += shift;
		shiftY += shift;
	}
	else{
		shiftX -= shift;
		shiftY -= shift;
	}
	glutPostRedisplay();
	glutTimerFunc(20, timer, 0);
}

float getParameterA(float  triangle[3][2]) {
	GLfloat centerX = (triangle[0][0] + triangle[1][0] + triangle[2][0]) / 3;
	GLfloat centerY = (triangle[0][1] + triangle[1][1] + triangle[2][1]) / 3;
	float a = centerY / centerX;
	return a;
}

void drawTriangle(float xy[3][2], int color) {
	glBegin(GL_TRIANGLES);
	setColor(color);
	glVertex2f(xy[0][0], xy[0][1]);
	glVertex2f(xy[1][0], xy[1][1]);
	glVertex2f(xy[2][0], xy[2][1]);
	glEnd();
}

// obrot wokol wlasnego srodka ciezkosci trojkata
void rotateTriangle(float angle, float x, float y, float triangle[3][2]) {
	GLfloat avgX = (triangle[0][0] + triangle[1][0] + triangle[2][0]) / 3;
	GLfloat avgY = (triangle[0][1] + triangle[1][1] + triangle[2][1]) / 3;
	glTranslatef(avgX, avgY, 0);
	glTranslatef(x, y, 0);
	glRotatef(angle, 0, 0, 1);
	glTranslatef(-avgX, -avgY, 0);
}

void drawMultipleTriangles(float angleCircle, float angleTriangle, float x, float y, float triangle[3][2], int color) {
	glPushMatrix();
	i = 0;
	glRotatef(angleCircle, 0, 0, 1);
	while(i <= 360) {
		i += 90;
		glPushMatrix();
		glRotatef(i, 0, 0, 1);
		glPushMatrix();
		rotateTriangle(angleTriangle, x, y, triangle);
		drawTriangle(triangle, color);
		glPopMatrix();
		glPopMatrix();
	}
	glPopMatrix();
}

void showTrangles() {
	drawMultipleTriangles(0, -0 * 2, shiftX, getParameterA(blueT) * shiftX, blueT, 1);
	drawMultipleTriangles(0, -0 * 2, shiftX, getParameterA(redT) * shiftX, redT, 2);
	drawMultipleTriangles(-0, 0 * 2, shiftX, getParameterA(greenT) * shiftX, greenT, 3);
	drawMultipleTriangles(0, -0 * 2, shiftX, getParameterA(yellowT) * shiftX, yellowT, 4);
	drawMultipleTriangles(0, -0 * 2, shiftX, getParameterA(pinkT) * shiftX, pinkT, 5);
	drawMultipleTriangles(-0, 0 * 2, shiftX, getParameterA(orangeT) * shiftX, orangeT, 6);
}

void MyDisplay(void) {
	// The new scene
	glLoadIdentity();
	glClear(GL_COLOR_BUFFER_BIT);
	showTrangles();
	glFlush();//start processing buffered OpenGL routines
}

void MyInit(void) {
	glClearColor(0.0, 0.0, 0.0, 0.0);//select clearing (background) color
									 /* initialize viewing values */
	glViewport(0, 0, 800, 800);//window origin and size
	glMatrixMode(GL_PROJECTION);//
	glLoadIdentity();//=1
	gluOrtho2D(-400, 400, -400, 400);
	glMatrixMode(GL_MODELVIEW);
	glLoadIdentity();//=1
}

int main(int argc, char** argv) {
	glutInit(&argc, argv);
	glutInitDisplayMode(GLUT_SINGLE | GLUT_RGB);//single buffer and RGBA
	glutInitWindowSize(800, 800);//initial window size
	glutInitWindowPosition(100, 100);
	glutCreateWindow("My window");//create widnow, hello title bar
	MyInit();
	glutDisplayFunc(MyDisplay);//
	glutTimerFunc(0, timer, 0);
	glutMainLoop();//enter main loop and process events
	return 0;
}