[MSPAINT] Mouse Wheel support (#4195)

Improve usability by mouse wheel handling. Plain wheel, Ctrl+Wheel, and Shift+Wheel. CORE-17937

base/applications/mspaint/common.h

@@ -26,3 +26,5 @@ static inline int UnZoomed(int xy)
 }
 
 #define GRIP_SIZE 3
+#define MIN_ZOOM 125
+#define MAX_ZOOM 8000

base/applications/mspaint/imgarea.cpp

@@ -172,7 +172,7 @@ LRESULT CImgAreaWindow::OnLButtonDown(UINT nMsg, WPARAM wParam, LPARAM lParam, B
         imageModel.Undo();
     }
     Invalidate(FALSE);
-    if ((toolsModel.GetActiveTool() == TOOL_ZOOM) && (toolsModel.GetZoom() < 8000))
+    if ((toolsModel.GetActiveTool() == TOOL_ZOOM) && (toolsModel.GetZoom() < MAX_ZOOM))
         zoomTo(toolsModel.GetZoom() * 2, GET_X_LPARAM(lParam), GET_Y_LPARAM(lParam));
     return 0;
 }
@@ -192,7 +192,7 @@ LRESULT CImgAreaWindow::OnRButtonDown(UINT nMsg, WPARAM wParam, LPARAM lParam, B
         imageModel.Undo();
     }
     Invalidate(FALSE);
-    if ((toolsModel.GetActiveTool() == TOOL_ZOOM) && (toolsModel.GetZoom() > 125))
+    if ((toolsModel.GetActiveTool() == TOOL_ZOOM) && (toolsModel.GetZoom() > MIN_ZOOM))
         zoomTo(toolsModel.GetZoom() / 2, GET_X_LPARAM(lParam), GET_Y_LPARAM(lParam));
     return 0;
 }
@@ -419,3 +419,8 @@ LRESULT CImgAreaWindow::OnImageModelImageChanged(UINT nMsg, WPARAM wParam, LPARA
     Invalidate(FALSE);
     return 0;
 }
+
+LRESULT CImgAreaWindow::OnMouseWheel(UINT nMsg, WPARAM wParam, LPARAM lParam, BOOL& bHandled)
+{
+    return ::SendMessage(GetParent(), nMsg, wParam, lParam);
+}

base/applications/mspaint/imgarea.h

@@ -24,6 +24,7 @@ public:
         MESSAGE_HANDLER(WM_LBUTTONUP, OnLButtonUp)
         MESSAGE_HANDLER(WM_RBUTTONUP, OnRButtonUp)
         MESSAGE_HANDLER(WM_MOUSEMOVE, OnMouseMove)
+        MESSAGE_HANDLER(WM_MOUSEWHEEL, OnMouseWheel)
         MESSAGE_HANDLER(WM_MOUSELEAVE, OnMouseLeave)
         MESSAGE_HANDLER(WM_IMAGEMODELDIMENSIONSCHANGED, OnImageModelDimensionsChanged)
         MESSAGE_HANDLER(WM_IMAGEMODELIMAGECHANGED, OnImageModelImageChanged)
@@ -42,6 +43,7 @@ private:
     LRESULT OnLButtonUp(UINT nMsg, WPARAM wParam, LPARAM lParam, BOOL& bHandled);
     LRESULT OnRButtonUp(UINT nMsg, WPARAM wParam, LPARAM lParam, BOOL& bHandled);
     LRESULT OnMouseMove(UINT nMsg, WPARAM wParam, LPARAM lParam, BOOL& bHandled);
+    LRESULT OnMouseWheel(UINT nMsg, WPARAM wParam, LPARAM lParam, BOOL& bHandled);
     LRESULT OnMouseLeave(UINT nMsg, WPARAM wParam, LPARAM lParam, BOOL& bHandled);
     LRESULT OnImageModelDimensionsChanged(UINT nMsg, WPARAM wParam, LPARAM lParam, BOOL& bHandled);
     LRESULT OnImageModelImageChanged(UINT nMsg, WPARAM wParam, LPARAM lParam, BOOL& bHandled);

base/applications/mspaint/scrollbox.cpp

@@ -179,3 +179,8 @@ LRESULT CScrollboxWindow::OnLButtonDown(UINT nMsg, WPARAM wParam, LPARAM lParam,
     pointSP = 0;    // resets the point-buffer of the polygon and bezier functions
     return 0;
 }
+
+LRESULT CScrollboxWindow::OnMouseWheel(UINT nMsg, WPARAM wParam, LPARAM lParam, BOOL& bHandled)
+{
+    return ::SendMessage(GetParent(), nMsg, wParam, lParam);
+}

base/applications/mspaint/scrollbox.h

@@ -18,12 +18,14 @@ public:
         MESSAGE_HANDLER(WM_HSCROLL, OnHScroll)
         MESSAGE_HANDLER(WM_VSCROLL, OnVScroll)
         MESSAGE_HANDLER(WM_LBUTTONDOWN, OnLButtonDown)
+        MESSAGE_HANDLER(WM_MOUSEWHEEL, OnMouseWheel)
     END_MSG_MAP()
 
     LRESULT OnSize(UINT nMsg, WPARAM wParam, LPARAM lParam, BOOL& bHandled);
     LRESULT OnHScroll(UINT nMsg, WPARAM wParam, LPARAM lParam, BOOL& bHandled);
     LRESULT OnVScroll(UINT nMsg, WPARAM wParam, LPARAM lParam, BOOL& bHandled);
     LRESULT OnLButtonDown(UINT nMsg, WPARAM wParam, LPARAM lParam, BOOL& bHandled);
+    LRESULT OnMouseWheel(UINT nMsg, WPARAM wParam, LPARAM lParam, BOOL& bHandled);
 };
 
 void UpdateScrollbox();

base/applications/mspaint/selection.cpp

@@ -280,3 +280,8 @@ LRESULT CSelectionWindow::OnSelectionModelRefreshNeeded(UINT nMsg, WPARAM wParam
     ForceRefreshSelectionContents();
     return 0;
 }
+
+LRESULT CSelectionWindow::OnMouseWheel(UINT nMsg, WPARAM wParam, LPARAM lParam, BOOL& bHandled)
+{
+    return ::SendMessage(GetParent(), nMsg, wParam, lParam);
+}

base/applications/mspaint/selection.h

@@ -22,6 +22,7 @@ public:
         MESSAGE_HANDLER(WM_SETCURSOR, OnSetCursor)
         MESSAGE_HANDLER(WM_LBUTTONDOWN, OnLButtonDown)
         MESSAGE_HANDLER(WM_MOUSEMOVE, OnMouseMove)
+        MESSAGE_HANDLER(WM_MOUSEWHEEL, OnMouseWheel)
         MESSAGE_HANDLER(WM_LBUTTONUP, OnLButtonUp)
         MESSAGE_HANDLER(WM_PALETTEMODELCOLORCHANGED, OnPaletteModelColorChanged)
         MESSAGE_HANDLER(WM_TOOLSMODELSETTINGSCHANGED, OnToolsModelSettingsChanged)
@@ -37,6 +38,7 @@ public:
     LRESULT OnSetCursor(UINT nMsg, WPARAM wParam, LPARAM lParam, BOOL& bHandled);
     LRESULT OnLButtonDown(UINT nMsg, WPARAM wParam, LPARAM lParam, BOOL& bHandled);
     LRESULT OnMouseMove(UINT nMsg, WPARAM wParam, LPARAM lParam, BOOL& bHandled);
+    LRESULT OnMouseWheel(UINT nMsg, WPARAM wParam, LPARAM lParam, BOOL& bHandled);
     LRESULT OnLButtonUp(UINT nMsg, WPARAM wParam, LPARAM lParam, BOOL& bHandled);
     LRESULT OnPaletteModelColorChanged(UINT nMsg, WPARAM wParam, LPARAM lParam, BOOL& bHandled);
     LRESULT OnToolsModelSettingsChanged(UINT nMsg, WPARAM wParam, LPARAM lParam, BOOL& bHandled);

base/applications/mspaint/toolsettings.cpp

@@ -255,7 +255,7 @@ LRESULT CToolSettingsWindow::OnToolsModelZoomChanged(UINT nMsg, WPARAM wParam, L
     int tbPos = 0;
     int tempZoom = toolsModel.GetZoom();
 
-    while (tempZoom > 125)
+    while (tempZoom > MIN_ZOOM)
     {
         tbPos++;
         tempZoom = tempZoom >> 1;

base/applications/mspaint/winproc.cpp

@@ -157,6 +157,56 @@ void CMainWindow::InsertSelectionFromHBITMAP(HBITMAP bitmap, HWND window)
     ForceRefreshSelectionContents();
 }
 
+LRESULT CMainWindow::OnMouseWheel(UINT nMsg, WPARAM wParam, LPARAM lParam, BOOL& bHandled)
+{
+    INT zDelta = (SHORT)HIWORD(wParam);
+
+    if (::GetAsyncKeyState(VK_CONTROL) < 0)
+    {
+        if (zDelta < 0)
+        {
+            if (toolsModel.GetZoom() > MIN_ZOOM)
+                zoomTo(toolsModel.GetZoom() / 2, 0, 0);
+        }
+        else if (zDelta > 0)
+        {
+            if (toolsModel.GetZoom() < MAX_ZOOM)
+                zoomTo(toolsModel.GetZoom() * 2, 0, 0);
+        }
+    }
+    else
+    {
+        UINT nCount = 3;
+        if (::GetAsyncKeyState(VK_SHIFT) < 0)
+        {
+#ifndef SPI_GETWHEELSCROLLCHARS
+    #define SPI_GETWHEELSCROLLCHARS 0x006C  // Needed for pre-NT6 PSDK
+#endif
+            SystemParametersInfoW(SPI_GETWHEELSCROLLCHARS, 0, &nCount, 0);
+            for (UINT i = 0; i < nCount; ++i)
+            {
+                if (zDelta < 0)
+                    ::PostMessageW(scrollboxWindow, WM_HSCROLL, MAKEWPARAM(SB_LINEDOWN, 0), 0);
+                else if (zDelta > 0)
+                    ::PostMessageW(scrollboxWindow, WM_HSCROLL, MAKEWPARAM(SB_LINEUP, 0), 0);
+            }
+        }
+        else
+        {
+            SystemParametersInfoW(SPI_GETWHEELSCROLLLINES, 0, &nCount, 0);
+            for (UINT i = 0; i < nCount; ++i)
+            {
+                if (zDelta < 0)
+                    ::PostMessageW(scrollboxWindow, WM_VSCROLL, MAKEWPARAM(SB_LINEDOWN, 0), 0);
+                else if (zDelta > 0)
+                    ::PostMessageW(scrollboxWindow, WM_VSCROLL, MAKEWPARAM(SB_LINEUP, 0), 0);
+            }
+        }
+    }
+
+    return 0;
+}
+
 LRESULT CMainWindow::OnDropFiles(UINT nMsg, WPARAM wParam, LPARAM lParam, BOOL& bHandled)
 {
     TCHAR droppedfile[MAX_PATH];

base/applications/mspaint/winproc.h

@@ -26,6 +26,7 @@ public:
         MESSAGE_HANDLER(WM_KEYDOWN, OnKeyDown)
         MESSAGE_HANDLER(WM_SYSCOLORCHANGE, OnSysColorChange)
         MESSAGE_HANDLER(WM_COMMAND, OnCommand)
+        MESSAGE_HANDLER(WM_MOUSEWHEEL, OnMouseWheel)
     END_MSG_MAP()
 
     LRESULT OnDropFiles(UINT nMsg, WPARAM wParam, LPARAM lParam, BOOL& bHandled);
@@ -39,6 +40,7 @@ public:
     LRESULT OnKeyDown(UINT nMsg, WPARAM wParam, LPARAM lParam, BOOL& bHandled);
     LRESULT OnSysColorChange(UINT nMsg, WPARAM wParam, LPARAM lParam, BOOL& bHandled);
     LRESULT OnCommand(UINT nMsg, WPARAM wParam, LPARAM lParam, BOOL& bHandled);
+    LRESULT OnMouseWheel(UINT nMsg, WPARAM wParam, LPARAM lParam, BOOL& bHandled);
 
     void alignChildrenToMainWindow();
     void saveImage(BOOL overwrite);