new: render.h

src/render.c

@@ -3,8 +3,7 @@
 #include <gsl/gsl_rng.h>
 #include <gsl/gsl_spline.h>
 #include <gsl/gsl_monte_miser.h>
-#include "common.h"
-#include "init.h"
+#include "render.h"
 
 typedef struct {
   const System *system;

src/render.h

@@ -0,0 +1,4 @@
+#include "common.h"
+#include "init.h"
+
+int render(System *system, double **buffer, int pixel_render_max, double pixel_render_err, double chi_rela_err);