Can rasterize polygons with holes using AGG. Export is raw ppm for now.

xs/src/libslic3r/Rasterizer/Rasterizer.hpp

@@ -1,6 +1,7 @@
 #ifndef RASTERIZER_HPP
 #define RASTERIZER_HPP
 
+#include <ostream>
 #include <Polygon.hpp>
 
 namespace Slic3r {
@@ -10,10 +11,18 @@ class Raster {
     std::unique_ptr<Impl> impl_;
 public:
 
+    enum class Compression {
+        RAW,
+        PNG
+    };
+
     struct Resolution {
         unsigned width_px;
         unsigned height_px;
         inline Resolution(unsigned w, unsigned h): width_px(w), height_px(h) {}
+        inline unsigned pixels() const /*noexcept*/ {
+            return width_px * height_px;
+        }
     };
 
     struct PixelDim {
@@ -23,7 +32,7 @@ public:
             w_mm(px_width_mm), h_mm(px_height_mm) {}
     };
 
-    inline explicit Raster(const Resolution& r, const PixelDim& pd );
+    explicit Raster(const Resolution& r, const PixelDim& pd );
     ~Raster();
     Raster(const Raster& cpy);
     Raster(Raster&& m);
@@ -32,11 +41,7 @@ public:
 
     void draw(const Polygon& poly);
 
-    void finish();
-
-private:
-    Resolution resolution_;
-    PixelDim pxdim_;
+    void save(std::ostream& stream, Compression comp = Compression::RAW);
 };
 
 }