mandelbrot_study/mandelbrot_kernel.cl

50 lines
1.2 KiB
Common Lisp

float map_x(int x, int width, float zoom)
{
return (((float)x / (float)width) * (3.5 * zoom)) - (2.5 - (1.0 - zoom));
}
float map_y(int y, int height, float zoom)
{
return (((float)y / (float)height) * (2.0 * zoom)) - (1.00001 - (1.0 - zoom));
}
__kernel void mandelbrot_point(__global const int *res_x,
__global const int *res_y,
__global const int *line,
__global const float *zoom,
__global int *graph_line)
{
// Get the index of the current element
int image_x = get_global_id(0);
int image_y = *line;
float pos_x = map_x(image_x, *res_x, *zoom);
float pos_y = map_y(image_y, *res_y, *zoom);
float x = 0.0;
float y = 0.0;
int iteration = 0;
int max_iteration = 256;
float xtemp, xx, yy;
while (iteration < max_iteration)
{
xx = x * x;
yy = y * y;
if ((xx) + (yy) > (4.0)) break;
xtemp = xx - yy + pos_x;
y = 2.0 * x * y + pos_y;
x = xtemp;
iteration++;
}
if (iteration > max_iteration)
{
graph_line[image_x] = 0;
}
else
{
graph_line[image_x] = iteration;
}
}