static void
compute_chunk(struct mandelbrot_param *args)
{
int i, j, val;
float Cim, Cre;
color_t pixel;
// Iterate through lines
for (i = args->begin_h; i < args->end_h; i++)
{
// Iterate through pixels in a line
for (j = args->begin_w; j < args->end_w; j++)
{
// Convert the coordinate of the pixel to be calculated to both
// real and imaginary parts of the complex number to be checked
Cim = (float) i / args->height * (args->upper_i - args->lower_i)
+ args->lower_i;
Cre = (float) j / args->width * (args->upper_r - args->lower_r)
+ args->lower_r;
// Gets the value returned by is_in_mandelbrot() and scale it
// from 0 to 255, or -1 if (Cre, Cim) is in the mandelbrot set.
val = is_in_Mandelbrot(Cre, Cim, args->maxiter);
// Change a negative value to 0 in val to make mandelbrot
// elements to appear black in the final picture.
pixel = val > args->maxiter ? args->mandelbrot_color : color[val
% num_colors(args)];
ppm_write(args->picture, j, i, pixel);
}
}
}
/***** You may modify this portion *****/
static void
compute_chunk(struct mandelbrot_param *args, int offseti, int offsetj)
{
int i, j, val;
float Cim, Cre;
color_t pixel;
//#pragma omp parallel for schedule(dynamic, 1) private(i,j,pixel,Cim,Cre,val)
for (i = 0; i < args->height; i++)
{
for (j = 0; j < args->width; j++)
{
// Convert the coordinate of the pixel to be calculated to both
// real and imaginary parts of the complex number to be checked
Cim = (float) i / args->height * (args->upper_i - args->lower_i)
+ args->lower_i;
Cre = (float) j / args->width * (args->upper_r - args->lower_r)
+ args->lower_r;
// Gets the value returned by is_in_mandelbrot() and scale it
// from 0 to 255, or -1 if (Cre, Cim) is in the mandelbrot set.
val = is_in_Mandelbrot(Cre, Cim, args->maxiter);
// Change a negative value to 0 in val to make mandelbrot
// elements to appear black in the final picture.
val = val > args->maxiter ? args->mandelbrot_color : color[val
% num_colors(args)];
// Permute green, red and blue to get different fancy colors
pixel.green = val >> 16 & 255;
pixel.red = val >> 8 & 255;
pixel.blue = val & 255;
ppm_write(args->picture, j + offsetj, i + offseti, pixel);
}
}
}
