float scale(float valueIn, float origMin, float origMax, float scaledMin, float scaledMax) { return ((scaledMax - scaledMin) * (valueIn - origMin) / (origMax - origMin)) + scaledMin; } __kernel void mandlebrot ( global int2* image_res, __write_only image2d_t image, global float4* range ){ size_t x_pixel = get_global_id(0); size_t y_pixel = get_global_id(1); int2 pixel = (int2)(x_pixel, y_pixel); float x0 = scale(x_pixel, 0, (*image_res).x, (*range).x, (*range).y); float y0 = scale(y_pixel, 0, (*image_res).y, (*range).z, (*range).w); float x = 0.0; float y = 0.0; int iteration_count = 0; int interation_threshold = 2000; while (x*x + y*y < 4 && iteration_count < interation_threshold) { float x_temp = x*x - y*y + x0; y = 2 * x * y + y0; x = x_temp; iteration_count++; } int val = scale(iteration_count, 0, 1000, 0, 16777216); //printf("%i", ((val >> 8) & 0xff)); float r = scale((val & 0xff), 0, 255, 0, 1); float g = scale((val >> 8) & 0xff, 0, 255, 0, 1); float b = scale((val >> 16) & 0xff, 0, 255, 0, 1); // write_imagei(image, pixel, (int4)((val & 0xff), ((val >> 8) & 0xff), ((val >> 16) & 0xff), 200)); write_imagef(image, pixel, (float4)(r, g, b, 200)); return; }