Ported CoolingBuffer to C++/XS

xs/src/libslic3r/GCode/CoolingBuffer.hpp

@@ -0,0 +1,39 @@
+#ifndef slic3r_CoolingBuffer_hpp_
+#define slic3r_CoolingBuffer_hpp_
+
+#include "libslic3r.h"
+#include "GCode.hpp"
+#include <map>
+#include <string>
+
+namespace Slic3r {
+
+/*
+A standalone G-code filter, to control cooling of the print.
+The G-code is processed per layer. Once a layer is collected, fan start / stop commands are edited
+and the print is modified to stretch over a minimum layer time.
+*/
+
+class CoolingBuffer {
+    public:
+    CoolingBuffer(GCode &gcodegen)
+        : _gcodegen(&gcodegen), _elapsed_time(0.), _layer_id(0)
+    {
+        this->_min_print_speed = this->_gcodegen->config.min_print_speed * 60;
+    };
+    std::string append(const std::string &gcode, std::string obj_id, size_t layer_id, float print_z);
+    std::string flush();
+    GCode* gcodegen() { return this->_gcodegen; };
+    
+    private:
+    GCode*                      _gcodegen;
+    std::string                 _gcode;
+    float                       _elapsed_time;
+    size_t                      _layer_id;
+    std::map<std::string,float> _last_z;
+    float                       _min_print_speed;
+};
+
+}
+
+#endif