Add vsync option to nosync0r filter

src/filter/nosync0r/nosync0r.cpp

@@ -10,21 +10,38 @@ class nosync0r : public frei0r::filter
   {
     hsync = 0.0;
     register_param(hsync,"HSync","the hsync offset");
+    vsync = 0.0;
+    register_param(vsync,"VSync","the vsync offset");
   }
 
   virtual void update(double time,
                       uint32_t* out,
                       const uint32_t* in)
   {
-    unsigned int
-      first_line=static_cast<unsigned int>(height*std::fmod(std::fabs(hsync),1.0));
+    if (hsync == 0.0 && vsync == 0.0) {
+        std::copy(in, in+width*height, out);
+    } else if (vsync == 0.0) {
+      unsigned int
+        first_line=static_cast<unsigned int>(height*std::fmod(std::fabs(hsync),1.0));
 
-    std::copy(in+width*first_line, in+width*height, out);
-    std::copy(in, in+width*first_line, out+width*(height-first_line));
+      std::copy(in+width*first_line, in+width*height, out);
+      std::copy(in, in+width*first_line, out+width*(height-first_line));
+    } else {
+        unsigned int hoffset=static_cast<unsigned int>(height*std::fmod(std::fabs(hsync),1.0));
+        unsigned int voffset=static_cast<unsigned int>(width*std::fmod(std::fabs(vsync),1.0));
+        for (unsigned int src_line = 0; src_line < height; src_line++) {
+            unsigned int dst_line = (src_line + hoffset) % height;
+            const uint32_t* src_pix = in + (width * src_line);
+            uint32_t* dst_pix = out + (width * dst_line);
+            std::copy(src_pix, src_pix + width - voffset, dst_pix + voffset);
+            std::copy(src_pix + width - voffset, src_pix + width, dst_pix);
+        }
+    }
   }
 
 private:
   double hsync;
+  double vsync;
 };