update: add openmp parallel

src/render.c

@@ -115,16 +115,22 @@ int render(System *system, double *buffer, int pixel_render_max, double pixel_re
 
   init(rmax, chi_rela_err, &size, &x, &y);
 
-  gsl_interp_accel *acc = gsl_interp_accel_alloc();
   gsl_spline *spline = gsl_spline_alloc(gsl_interp_steffen, size);
-  Spline_data spline_data = {spline, acc};
   gsl_spline_init(spline, x, y, size);
 
-  for(int j = 0; j < H; j++) {
+  #pragma omp parallel
-    for (int i = 0; i < W; i++) {
+  {
-      pixel_render(system, i, j, spline_data, buffer+color_index(i,j,0), pixel_render_max, pixel_render_err, r);
+    gsl_interp_accel *acc = gsl_interp_accel_alloc();
-    }
+    Spline_data spline_data = {spline, acc};
-  }
     
+    #pragma omp for
+    for(int j = 0; j < H; j++) {
+      for (int i = 0; i < W; i++) {
+        pixel_render(system, i, j, spline_data, buffer+color_index(i,j,0), pixel_render_max, pixel_render_err, r);
+      }
+    }
+
+    gsl_interp_accel_free(acc);
+  }
   return 0;
 }