diff --git a/CHANGELOG.md b/CHANGELOG.md
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,13 @@
+5.16
+API changes:
+  - Added support for mouse wheel events while in mouse mode. The Button
+    type got two new constructors as a result: BScrollUp and BScrollDown.
+    Thanks to doublescale@tutanota.com for this contribution!
+
+Bug fixes:
+  - charFill now clamps negative arguments to zero (thanks Eric
+    Mertens!)
+
 5.15.1
 Package changes:
   - Documentation files are now marked accordingly (thanks Michal
diff --git a/src/Graphics/Vty/Image.hs b/src/Graphics/Vty/Image.hs
--- a/src/Graphics/Vty/Image.hs
+++ b/src/Graphics/Vty/Image.hs
@@ -171,6 +171,9 @@
 utf8Bytestring' a bs = text' a (T.decodeUtf8 bs)
 
 -- | Make an image filling a region with the specified character.
+--
+-- If either the width or height are less than or equal to 0, then
+-- the result is the empty image.
 charFill :: Integral d
          => Attr
          -- ^ The attribute to use.
@@ -181,14 +184,17 @@
          -> d
          -- ^ The region height.
          -> Image
-charFill _a _c 0  _h = EmptyImage
-charFill _a _c _w 0  = EmptyImage
-charFill a c w h =
-    vertCat $ replicate (fromIntegral h) $ HorizText a txt displayWidth charWidth
-    where
-        txt = TL.replicate (fromIntegral w) (TL.singleton c)
-        displayWidth = safeWcwidth c * (fromIntegral w)
-        charWidth = fromIntegral w
+charFill a c w h
+  | w <= 0 || h <= 0 = EmptyImage
+  | otherwise        = vertCat
+                     $ replicate (fromIntegral h)
+                     $ HorizText a txt displayWidth charWidth
+  where
+    txt          = TL.replicate charWidth (TL.singleton c)
+    displayWidth = safeWcwidth c * charWidth
+
+    charWidth   :: Num a => a
+    charWidth    = fromIntegral w
 
 -- | The empty image. Useful for fold combinators. These occupy no space
 -- and do not affect display attributes.
diff --git a/src/Graphics/Vty/Input/Events.hs b/src/Graphics/Vty/Input/Events.hs
--- a/src/Graphics/Vty/Input/Events.hs
+++ b/src/Graphics/Vty/Input/Events.hs
@@ -28,7 +28,7 @@
     deriving (Eq,Show,Read,Ord,Generic)
 
 -- | Mouse buttons.
-data Button = BLeft | BMiddle | BRight
+data Button = BLeft | BMiddle | BRight | BScrollUp | BScrollDown
     deriving (Eq,Show,Read,Ord,Generic)
 
 -- | Events.
diff --git a/src/Graphics/Vty/Input/Mouse.hs b/src/Graphics/Vty/Input/Mouse.hs
--- a/src/Graphics/Vty/Input/Mouse.hs
+++ b/src/Graphics/Vty/Input/Mouse.hs
@@ -67,7 +67,7 @@
 
 -- These bits indicate the buttons involved:
 buttonMask :: Int
-buttonMask = 3
+buttonMask = 67
 
 leftButton :: Int
 leftButton = 0
@@ -78,6 +78,12 @@
 rightButton :: Int
 rightButton = 2
 
+scrollUp :: Int
+scrollUp = 64
+
+scrollDown :: Int
+scrollDown = 65
+
 hasBitSet :: Int -> Int -> Bool
 hasBitSet val bit = val .&. bit > 0
 
@@ -100,6 +106,8 @@
     let buttonMap = [ (leftButton,   BLeft)
                     , (middleButton, BMiddle)
                     , (rightButton,  BRight)
+                    , (scrollUp,     BScrollUp)
+                    , (scrollDown,   BScrollDown)
                     ]
     in case lookup (mods .&. buttonMask) buttonMap of
         Nothing -> failParse
diff --git a/vty.cabal b/vty.cabal
--- a/vty.cabal
+++ b/vty.cabal
@@ -1,5 +1,5 @@
 name:                vty
-version:             5.15.1
+version:             5.16
 license:             BSD3
 license-file:        LICENSE
 author:              AUTHORS
@@ -38,7 +38,7 @@
 
 library
   default-language:    Haskell2010
-  build-depends:       base >= 4.6 && < 5,
+  build-depends:       base >= 4.8 && < 5,
                        blaze-builder >= 0.3.3.2 && < 0.5,
                        bytestring,
                        containers,
@@ -125,7 +125,7 @@
   ghc-options:         -threaded
 
   build-depends:       vty,
-                       base >= 4.6 && < 5,
+                       base >= 4.8 && < 5,
                        containers,
                        microlens,
                        microlens-mtl,
@@ -140,7 +140,7 @@
   ghc-options:         -threaded
 
   build-depends:       vty,
-                       base >= 4.6 && < 5,
+                       base >= 4.8 && < 5,
                        containers,
                        microlens,
                        microlens-mtl,
@@ -156,7 +156,7 @@
                        Cabal >= 1.20,
                        QuickCheck >= 2.7,
                        random >= 1.0 && < 1.2,
-                       base >= 4.6 && < 5,
+                       base >= 4.8 && < 5,
                        bytestring,
                        containers,
                        deepseq >= 1.1 && < 1.5,
@@ -188,7 +188,7 @@
                        Cabal >= 1.20,
                        QuickCheck >= 2.7,
                        random >= 1.0 && < 1.2,
-                       base >= 4.6 && < 5,
+                       base >= 4.8 && < 5,
                        bytestring,
                        containers,
                        deepseq >= 1.1 && < 1.5,
@@ -221,7 +221,7 @@
                        Cabal >= 1.20,
                        QuickCheck >= 2.7,
                        random >= 1.0 && < 1.2,
-                       base >= 4.6 && < 5,
+                       base >= 4.8 && < 5,
                        bytestring,
                        containers,
                        deepseq >= 1.1 && < 1.5,
@@ -254,7 +254,7 @@
                        Cabal >= 1.20,
                        QuickCheck >= 2.7,
                        random >= 1.0 && < 1.2,
-                       base >= 4.6 && < 5,
+                       base >= 4.8 && < 5,
                        bytestring,
                        containers,
                        deepseq >= 1.1 && < 1.5,
@@ -280,7 +280,7 @@
                        Cabal >= 1.20,
                        QuickCheck >= 2.7,
                        random >= 1.0 && < 1.2,
-                       base >= 4.6 && < 5,
+                       base >= 4.8 && < 5,
                        bytestring,
                        containers,
                        deepseq >= 1.1 && < 1.5,
@@ -307,7 +307,7 @@
                        Cabal >= 1.20,
                        QuickCheck >= 2.7,
                        random >= 1.0 && < 1.2,
-                       base >= 4.6 && < 5,
+                       base >= 4.8 && < 5,
                        blaze-builder >= 0.3.3.2 && < 0.5,
                        bytestring,
                        containers,
@@ -337,7 +337,7 @@
                        Cabal >= 1.20,
                        QuickCheck >= 2.7,
                        random >= 1.0 && < 1.2,
-                       base >= 4.6 && < 5,
+                       base >= 4.8 && < 5,
                        bytestring,
                        containers,
                        deepseq >= 1.1 && < 1.5,
@@ -365,7 +365,7 @@
                        Cabal >= 1.20,
                        QuickCheck >= 2.7,
                        random >= 1.0 && < 1.2,
-                       base >= 4.6 && < 5,
+                       base >= 4.8 && < 5,
                        bytestring,
                        containers,
                        deepseq >= 1.1 && < 1.5,
@@ -392,7 +392,7 @@
                        Cabal >= 1.20,
                        QuickCheck >= 2.7,
                        random >= 1.0 && < 1.2,
-                       base >= 4.6 && < 5,
+                       base >= 4.8 && < 5,
                        bytestring,
                        containers,
                        deepseq >= 1.1 && < 1.5,
@@ -420,7 +420,7 @@
                        Cabal >= 1.20,
                        QuickCheck >= 2.7,
                        random >= 1.0 && < 1.2,
-                       base >= 4.6 && < 5,
+                       base >= 4.8 && < 5,
                        bytestring,
                        containers,
                        deepseq >= 1.1 && < 1.5,
@@ -452,7 +452,7 @@
                        Cabal >= 1.20,
                        QuickCheck >= 2.7,
                        random >= 1.0 && < 1.2,
-                       base >= 4.6 && < 5,
+                       base >= 4.8 && < 5,
                        bytestring,
                        containers,
                        deepseq >= 1.1 && < 1.5,
@@ -484,7 +484,7 @@
                        Cabal >= 1.20,
                        QuickCheck >= 2.7,
                        random >= 1.0 && < 1.2,
-                       base >= 4.6 && < 5,
+                       base >= 4.8 && < 5,
                        bytestring,
                        containers,
                        deepseq >= 1.1 && < 1.5,
@@ -516,7 +516,7 @@
                        Cabal >= 1.20,
                        QuickCheck >= 2.7,
                        random >= 1.0 && < 1.2,
-                       base >= 4.6 && < 5,
+                       base >= 4.8 && < 5,
                        bytestring,
                        containers,
                        deepseq >= 1.1 && < 1.5,
@@ -542,7 +542,7 @@
                        Cabal >= 1.20,
                        QuickCheck >= 2.7,
                        random >= 1.0 && < 1.2,
-                       base >= 4.6 && < 5,
+                       base >= 4.8 && < 5,
                        bytestring,
                        containers,
                        deepseq >= 1.1 && < 1.5,
@@ -570,7 +570,7 @@
                        test-framework == 0.8.*,
                        test-framework-smallcheck == 0.2.*,
                        random >= 1.0 && < 1.2,
-                       base >= 4.6 && < 5,
+                       base >= 4.8 && < 5,
                        bytestring,
                        containers,
                        deepseq >= 1.1 && < 1.5,
@@ -606,7 +606,7 @@
                        test-framework-smallcheck == 0.2.*,
                        test-framework-hunit,
                        random >= 1.0 && < 1.2,
-                       base >= 4.6 && < 5,
+                       base >= 4.8 && < 5,
                        bytestring,
                        containers,
                        deepseq >= 1.1 && < 1.5,