main.cpp

#include <stdio.h>
#include <stdlib.h>
#include <math.h>
#include <GL/glut.h> // áèáëèîòåêà OpenGL
#include <omp.h> //áèáëèîòåêà äëÿ ïàðàëëåëüíûõ âû÷èñëåíèé

typedef struct {
	GLbyte r, g, b;
} Pixel;

typedef struct {
	GLdouble real, imag;
} Complex;

//ðàçìåð îêíà
#define width 1280
#define height 720

Pixel image[height][width];

GLuint texture;
Pixel dark_blue;

int window_id;

//Îáëàñòü äëÿ ðèñîâàíèÿ
double real_min = -2.9; //ëåâàÿ ãðàíèöà
double real_max = 1.4; //ïðàâàÿ ãðàíèöà
double img_min = -1.2; //âåðõíÿÿ ãðàíèöà
double img_max = img_min + (real_max - real_min)*height / width; //íèæíÿÿ ãðàíèöà
														 
double real_factor = (real_max - real_min) / (width - 1); //ðåàëüíûé ìíîæåòåëü
double imag_factor = (img_max - img_min) / (height - 1);  //ìíèìûé ìíîæèòåëü

int max = omp_get_max_threads(); //îïðåäåëÿåì ìàêñèìàëüíîå êîë-âî ïîòîêîâ
int iterations = 0, thread_count = max, step = 1, color_profile = 1;

//Îòîáðàæåíèå öâåòà
Pixel mapping[16];

void RenderFrame()
{
	double real_factor = (real_max - real_min) / (width - 1);
	double imag_factor = (img_max - img_min) / (height - 1);
	double color_step = (double)iterations / 256;
	double start_time = omp_get_wtime();

	//ïàðàëëåëüíûé öèêë äëÿ âû÷èñëåíèé
#pragma omp parallel for num_threads(thread_count)
	for (int y = 0; y < height; ++y)
	{
		double c_im = img_max - y*imag_factor;
		for (unsigned x = 0; x < width; ++x)
		{
			double c_re = real_min + x*real_factor;
			double Z_re = c_re, Z_im = c_im;
			bool isInside = true;
			unsigned n;
			for (n = 0; n < iterations; ++n) 
			{
				double Z_re2 = Z_re*Z_re, Z_im2 = Z_im*Z_im;
				if (Z_re2 + Z_im2 > 4)
				{
					isInside = false;
					break;
				}
				Z_im = 2 * Z_re*Z_im + c_im;
				Z_re = Z_re2 - Z_im2 + c_re;
			}

			if (isInside)
			{
				Pixel p;
				p.r = 0;
				p.g = 0;
				p.b = 0;
				image[y][x] = p;
			}
			else 
			{
				unsigned dn = n;
				double color = (double)dn / color_step;
				int nc = (int)color;
				Pixel p;
				switch (color_profile)
				{
				case 1:
					if (n < iterations && n > 0)
 {
						int id = n % 16;
						p = mapping[id];
					}
					break;
				case 2:
					p.r = 0;
					p.g = nc;
					p.b = 0;
					break;
				case 3:
					p.r = 0;
					p.g = 0;
					p.b = nc;
					break;
				case 4:
					p.r = nc;
					p.g = 0;
					p.b = nc;
					break;
				case 5:
					p.r = nc;
					p.g = 0;
					p.b = 0;
					break;
				default:
					break;
				}
				image[y][x] = p;
			}
		}
	}
	double end_time = omp_get_wtime();
	printf("Render time: %f\n", end_time - start_time);
}

//Îïðåäåëåíèå öâåòà äëÿ ïîêàçà ðàçëè÷íûõ óðîâíåé
void init_color_mapping() 
{
	mapping[0].r = 66; mapping[0].g = 30; mapping[0].b = 15;
	mapping[1].r = 25; mapping[1].g = 7; mapping[1].b = 26;
	mapping[2].r = 9; mapping[2].g = 1; mapping[2].b = 47;
	mapping[3].r = 4; mapping[3].g = 4; mapping[3].b = 73;
	mapping[4].r = 0; mapping[4].g = 7; mapping[4].b = 100;
	mapping[5].r = 12; mapping[5].g = 44; mapping[5].b = 138;
	mapping[6].r = 24; mapping[6].g = 82; mapping[6].b = 177;
	mapping[7].r = 57; mapping[7].g = 125; mapping[7].b = 209;
	mapping[8].r = 134; mapping[8].g = 181; mapping[8].b = 229;
	mapping[9].r = 211; mapping[9].g = 236; mapping[9].b = 248;
	mapping[10].r = 241; mapping[10].g = 233; mapping[10].b = 191;
	mapping[11].r = 248; mapping[11].g = 201; mapping[11].b = 95;
	mapping[12].r = 255; mapping[12].g = 170; mapping[12].b = 0;
	mapping[13].r = 204; mapping[13].g = 128; mapping[13].b = 0;
	mapping[13].r = 153; mapping[13].g = 87; mapping[13].b = 0;
	mapping[13].r = 106; mapping[13].g = 52; mapping[13].b = 3;
}

// Èíèöèèëèçàöèÿ ñîñòîÿíèé OpenGL
void init() 
{
	// Íàñòðîéêà òåêñòóð
	glEnable(GL_TEXTURE_2D);
	glGenTextures(1, &texture);
	glBindTexture(GL_TEXTURE_2D, texture);
	glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
	glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
	glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP);
	glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP);

	// Äðóãîå
	glClearColor(0, 0, 0, 0);
	gluOrtho2D(-1, 1, -1, 1);
	glLoadIdentity();
	glColor3f(1, 1, 1);
	init_color_mapping();
}

// Ãåíåðàöèÿ è îòîáðàæåíèå èçîáðàæåíèÿ
void display() 
{
	// Âûçîâ ïîëüçîâàòåëåì ãåíåðàöèè èçîáðàæåíèÿ
	RenderFrame();

	// Êîïèðîâàíèÿ òåêñòóð èçîáðàæåíèÿ â ïàìÿòü
	glBindTexture(GL_TEXTURE_2D, texture);
	glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, width, height, 0, GL_RGB, GL_UNSIGNED_BYTE, image);

	// Î÷èñòêà áóôåðà
	glClear(GL_COLOR_BUFFER_BIT);

	// Ðåíäåð
	glBegin(GL_QUADS);
	glTexCoord2f(1, 0); glVertex2f(1, -1);
	glTexCoord2f(1, 1); glVertex2f(1, 1);
	glTexCoord2f(0, 1); glVertex2f(-1, 1);
	glTexCoord2f(0, 0); glVertex2f(-1, -1);
	glEnd();

	// Îòîáðàæåíèå ðåçóëüòàòàò
	glFlush();
	glutSwapBuffers();

}

//Óïðàâëåíèå ñ êëàâèàòóðû
void keypress(unsigned char key, int x, int y) 
{
	double real_diff = fabs(real_min - real_max) * 0.05;
	double img_diff = fabs(img_min - img_max) * 0.05;

	switch (key) 
	{
		//Ïðèáëèæåíèå
	case 'S':
	case 's':
		real_min -= real_diff;
		real_max += real_diff;
		img_min -= img_diff;
		img_max += img_diff;
		break;
		//Îòäàëåíèå
	case 'W':
	case 'w':
		real_min += real_diff;
		real_max -= real_diff;
		img_min += img_diff;
		img_max -= img_diff;
		break;
		//Óìåíüøèòü êîë-âî èòåðàöèé
	case 'A':
	case 'a':
		if (iterations > step) iterations -= step;
		printf("Iterations:\t%d\n", iterations);
		break;
		//Óâåëè÷èòü êîë-âî èòåðàöèé
	case 'D':
	case 'd':
		iterations += step;
		printf("Iterations:\t%d\n", iterations);
		break;
		//Óâåëè÷ü êîë-âî øàãîâ
	case 'E':
	case 'e':
		step++;
		printf("Step:\t%d\n", step);
		break;
		//Óìåíüøèòü êîë-âî øàãîâ
	case 'Q':
	case 'q':
		if (step > 1) step--;
		printf("Step:\t%d\n", step);
		break;
		//Óâåëè÷èòü êîë-âî èñïîëüçîâàííûõ ïîòîêîâ
	case 'L':
	case 'l':
		thread_count += 1;
		printf("Threads:\t%d\n", thread_count);
		break;
		//Óìåíüøèòü êîë-âî èñïîëüçîâàííûõ ïîòîêîâ
	case 'K':
	case 'k':
		if (thread_count > 1) thread_count -= 1;
		printf("Threads:\t%d\n", thread_count);
		break;
		//Ïîìåíÿòü öâåò
	case 'C':
	case 'c':
		color_profile++;
		if (color_profile > 5) color_profile = 1;
		printf("Color profile changed\n");
		break;
		//Âûõîä
	case 27:
		glutDestroyWindow(window_id);
		exit(EXIT_SUCCESS);
		break;
	default:
		break;
	}
	// Îáíîâëåíèÿ îêíà
	glutPostRedisplay();
}

void SpecialKeys(int key, int x, int y)
{

	double realDif = fabs(real_min - real_max) * 0.05;
	double imagDif = fabs(img_min - img_max) * 0.05;

	switch (key)
	{
	case (char)GLUT_KEY_UP:
		img_min -= imagDif;
		img_max -= imagDif;
		break;
	case GLUT_KEY_DOWN:
		img_min += imagDif;
		img_max += imagDif;
		break;
	case GLUT_KEY_RIGHT:
		real_min += realDif;
		real_max += realDif;
		break;
	case GLUT_KEY_LEFT:
		real_min -= realDif;
		real_max -= realDif;
		break;
	default:
		break;
	}
	// Îáíîâëåíèÿ îêíà
	glutPostRedisplay();
}

// Main
int main(int argc, char ** argv)
{
	// Èíèöèëèçàöèÿ GLUT
	glutInit(&argc, argv);
	glutInitWindowSize(width, height);
	glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGB | GLUT_DEPTH);
	window_id = glutCreateWindow("Mandelbrot Set");

	// Çàïóñê ôóíêöèé äëÿ óïðàâëåíèÿ
	glutSpecialFunc(SpecialKeys);
	glutKeyboardFunc(keypress);
	glutDisplayFunc(display);

	init();

	// Çàïóñê ìåõàíèçìà îáðàáîòêè ñîáûòèé
	glutMainLoop();

	return EXIT_SUCCESS;
}