3 files changed, 17 insertions, 4 deletions
diff --git a/plugingui/painter.cc b/plugingui/painter.cc
index b74952f..e5da246 100644
--- a/plugingui/painter.cc
+++ b/plugingui/painter.cc
@@ -191,9 +191,16 @@ void GUI::Painter::drawRectangle(int x1, int y1, int x2, int y2)
 
 void GUI::Painter::drawFilledRectangle(int x1, int y1, int x2, int y2)
 {
-  for(int x = x1; x < x2; x++) {
-    for(int y = y1; y < y2; y++) {
-      drawPoint(x, y);
+  for(int y = y1; y < y2; y++) {
+    drawLine(x1, y, x2, y);
+  }
+}
+
+void GUI::Painter::clear()
+{
+  for(int x = 0; x < pixbuf->width; x++) {
+    for(int y = 0; y < pixbuf->height; y++) {
+      pixbuf->setPixel(x, y, 0, 0, 0, 0);
     }
   }
 }
diff --git a/plugingui/painter.h b/plugingui/painter.h
index b45cf3a..f236369 100644
--- a/plugingui/painter.h
+++ b/plugingui/painter.h
@@ -68,6 +68,8 @@ public:
   void drawFilledCircle(int x, int y, int r);
   void drawImage(int x, int y, struct __img__ * img);
 
+  void clear();
+
 private:
   void plot(int x, int y, double c);
   double ipart(double x);
diff --git a/plugingui/pixelbuffer.cc b/plugingui/pixelbuffer.cc
index e9e376a..c0dc2cc 100644
--- a/plugingui/pixelbuffer.cc
+++ b/plugingui/pixelbuffer.cc
@@ -114,7 +114,11 @@ void GUI::PixelBufferAlpha::addPixel(size_t x, size_t y,
   buf[PX(2)] = (unsigned char)(blue * a + buf[PX(2)] * (1-a));
 
   //buf[PX(3)] = (unsigned char)(alpha * a + buf[PX(3)] * (1-a));
-  buf[PX(3)] = alpha>buf[PX(3)]?alpha:buf[PX(3)];
+  //buf[PX(3)] = alpha>buf[PX(3)]?alpha:buf[PX(3)];
+
+  float a1 = (float)buf[PX(3)] / 255.0;
+  float a2 = (float)alpha / 255.0;
+  buf[PX(3)] = (a1 + ((1 - a1) * a2)) * 255.0;
 }
 
 void GUI::PixelBufferAlpha::pixel(size_t x, size_t y,