Generates ASCII art Mandelbrot set using CUDA. Make sure to set your terminal font size as small as possible and adjust the parameters to fit your setup.

Mandelbrot.cu

#include "cuda_runtime.h"
#include "device_launch_parameters.h"

#include <stdio.h>
#include <stdlib.h>

//MAKE SURE TO SET TERMINAL FONT SIZE AS SMALL AS POSSIBLE

#define WIDTH 940 //In chars, adjust to screen
#define HEIGHT 220

#define MINR -2.5 // Min/max x values
#define MAXR 1.0

#define MINI -1.0 // Min/max y values
#define MAXI 1.0

#define MAXITERS 222 //Number of iterations, up to 222

//Leave this alone
#define TPB 32
#define GRIDX ((WIDTH-1)/TPB)+1
#define GRIDY ((HEIGHT-1)/TPB)+1



__global__ void mandlebrot(unsigned int* outputIters)
{
	double posx = (blockIdx.x * blockDim.x) + threadIdx.x;//Get global position
	double posy = (blockIdx.y * blockDim.y) + threadIdx.y;

	if (posx >= WIDTH || posy >= HEIGHT) return;//Array safety

	double scalex = (MAXR - MINR) / WIDTH; //Determine scaling
	double scaley = (MAXI - MINI) / HEIGHT;
	
	double addr = (scalex*posx) + MINR;
	double addi = (scaley*posy) + MINI;

	double rval = 0;
	double ival = 0;

	int iter = 0;

	//While MAXITERS hasn't been reached and the magnitude is less than 2
	while ((iter <= MAXITERS) && ((rval*rval) + (ival * ival) < 4)){

		double newR = (rval*rval) - (ival*ival) + addr;
		double newI = (2 * rval*ival) + addi;

		rval = newR;
		ival = newI;

		iter++;
	}

	unsigned int outputLoc = (posy*WIDTH) + posx;//Determine output position

	outputIters[outputLoc] = iter;


}

int main()
{

	//Allocate device array
	unsigned int* d_output;
	cudaMalloc(&d_output, WIDTH*HEIGHT*sizeof(unsigned int));

	
	dim3 gridSz(GRIDX, GRIDY);
	dim3 blockSz(TPB, TPB);

	//Generate set
	mandlebrot<<<gridSz,blockSz>>>(d_output);

	//Copy set back over
	unsigned int* h_output = (unsigned int*) malloc(WIDTH*HEIGHT*sizeof(unsigned int));

	cudaMemcpy(h_output, d_output, HEIGHT*WIDTH*sizeof(unsigned int), cudaMemcpyDeviceToHost);

	//Print it out
	for (int i = 0; i < (WIDTH*HEIGHT); i++){
		printf("%c", (MAXITERS+33)-h_output[i]);
		if (i%WIDTH == (WIDTH - 1)) printf("\n");
	}

	cudaFree(d_output);
	free(h_output);

	//Pause at end
	getchar();

}