basic 3D object draw in terminal

3dascii.c

// Dimitar T. Dimitrov 2017
#include <stdio.h>
#include <unistd.h>
#include <string.h>
#include <math.h>

const int width = 64;
const int height = 64;

char screen[width * height];

float o[8][3] = {
	{ 1, -1, -1},
	{ 1, -1,  1},
	{-1, -1,  1},
	{-1, -1, -1},
	{ 1,  1, -1},
	{ 1,  1,  1},
	{-1,  1,  1},
	{-1,  1, -1}};

int camx = 30;
int camy = 40;
int camz = 3;

void set(int x, int y, char c) {
	int i = y * width + x;
	if ((i > (width * height)) || i < 0)
		return;

	screen[i] = c;
}

void rotate(float *x, float *y, float angle) {
	float cs = cos(angle);
	float sn = sin(angle);

	float tmp = cs * (*x) - sn * (*y);
	*y = sn * (*x) + cs * (*y);
	*x = tmp;
}

int main() {
	while(42) {
		memset(screen, ' ', width * height);
		for (int i = 0; i < width * height; i += width)
			screen[i] = 0x0a;
		screen[width * height - 1] = 0;

		for (int i = 0; i < 8; i++) {
			int x = (int) (o[i][0] * 10 / (o[i][2] + camz) + camx);
			int y = (int) (o[i][1] * 10 / (o[i][2] + camz) + camy);

			rotate(&o[i][0], &o[i][1], 0.2f);
			rotate(&o[i][2], &o[i][0], 0.1f);
			set(x, y, 46);
		}
		printf("\x1b[2J%s\n", screen);
		usleep(100000);
	}

	return 0;
}