[MSPAINT] Update cursor shape for brush and rubber (#8974)

Improve UI/UX by updating mouse
cursor shape.
JIRA issue: CORE-20520
- Add CStyledCursor class.
- Enhance CCanvasWindow::OnSetCursor
  for TOOL_BRUSH and TOOL_RUBBER.
- Add CCanvasWindow::m_hBrushCursor
  CCanvasWindow::m_hRubberCursor to
  keep cursor shapes.
- Send WM_SETCURSOR from ToolsModel
  to update the cursor shape.
Co-authored-by: Hermès BÉLUSCA - MAÏTO <[email protected]>

base/applications/mspaint/canvas.cpp

@@ -3,6 +3,7 @@
  * LICENSE:    LGPL-2.0-or-later (https://spdx.org/licenses/LGPL-2.0-or-later)
  * PURPOSE:    Providing the canvas window class
  * COPYRIGHT:  Copyright 2015 Benedikt Freisen <[email protected]>
+ *             Copyright 2026 Katayama Hirofumi MZ <[email protected]>
  */
 
 #include "precomp.h"
@@ -11,6 +12,137 @@ CCanvasWindow canvasWindow;
 
 /* FUNCTIONS ********************************************************/
 
+HCURSOR
+CStyledCursor::CreateStyledCursor(BrushStyle style, INT radius, COLORREF color, BOOL is_rubber)
+{
+    const INT diameter = 2 * radius;
+    if (diameter <= 2)
+    {
+        HCURSOR hCursor = ::LoadCursor(NULL, IDC_CROSS);
+        return hCursor ? CopyCursor(hCursor) : NULL;
+    }
+
+    const INT crosshair1 = 6, crosshair2 = crosshair1 - 2;
+    const INT width = diameter + 2 * crosshair1, height = diameter + 2 * crosshair1;
+    const DWORD hotX = width / 2, hotY = height / 2;
+
+    HDC hdcScreen = ::GetDC(NULL);
+    if (!hdcScreen)
+        return NULL;
+    HDC hdcMem = ::CreateCompatibleDC(hdcScreen);
+    if (!hdcMem)
+    {
+        ::ReleaseDC(NULL, hdcScreen);
+        return NULL;
+    }
+
+    RECT rc = { 0, 0, width, height };
+
+    // Create the AND mask bitmap. This must be monochrome (1bpp):
+    // white bits are transparent, black bits are opaque.
+    HBITMAP hbmMask = ::CreateBitmap(width, height, 1, 1, NULL);
+    if (hbmMask)
+    {
+        HBITMAP hbmOld = (HBITMAP)::SelectObject(hdcMem, hbmMask);
+
+        // Fill with white brush
+        ::FillRect(hdcMem, &rc, (HBRUSH)::GetStockObject(WHITE_BRUSH));
+
+        if (!is_rubber)
+        {
+            // Draw crosshair with white pen
+            ::SelectObject(hdcMem, (HPEN)::GetStockObject(WHITE_PEN));
+            ::MoveToEx(hdcMem, 0, hotY, NULL);
+            ::LineTo(hdcMem, crosshair2, hotY);
+            ::MoveToEx(hdcMem, width - crosshair2, hotY, NULL);
+            ::LineTo(hdcMem, width, hotY);
+            ::MoveToEx(hdcMem, hotX, 0, NULL);
+            ::LineTo(hdcMem, hotX, crosshair2);
+            ::MoveToEx(hdcMem, hotX, height - crosshair2, NULL);
+            ::LineTo(hdcMem, hotX, height);
+        }
+
+        // Draw brush or erase with black color
+        if (is_rubber)
+            Erase(hdcMem, hotX, hotY, hotX, hotY, RGB(0, 0, 0), radius + 1);
+        else
+            Brush(hdcMem, hotX, hotY, hotX, hotY, RGB(0, 0, 0), style, diameter);
+
+        if (is_rubber)
+            InflateRect(&rc, -1, -1);
+
+        ::SelectObject(hdcMem, hbmOld);
+    }
+
+    // Create the color (XOR) bitmap
+    HBITMAP hbmColor = ::CreateCompatibleBitmap(hdcScreen, width, height);
+    if (hbmColor)
+    {
+        HBITMAP hbmOld = (HBITMAP)::SelectObject(hdcMem, hbmColor);
+
+        // Fill with black brush
+        ::FillRect(hdcMem, &rc, (HBRUSH)::GetStockObject(BLACK_BRUSH));
+
+        if (is_rubber)
+        {
+            // Draw for rubber border
+            INT avg = (GetRValue(color) + GetGValue(color) + GetBValue(color)) / 3;
+            COLORREF color2 = (avg > 255 / 2) ? RGB(0, 0, 0) : RGB(255, 255, 255);
+            Erase(hdcMem, hotX, hotY, hotX, hotY, color2, radius + 1);
+        }
+        else
+        {
+            // Draw crosshair with white pen
+            ::SelectObject(hdcMem, (HPEN)::GetStockObject(WHITE_PEN));
+            ::MoveToEx(hdcMem, 0, hotY, NULL);
+            ::LineTo(hdcMem, crosshair2, hotY);
+            ::MoveToEx(hdcMem, width - crosshair2, hotY, NULL);
+            ::LineTo(hdcMem, width, hotY);
+            ::MoveToEx(hdcMem, hotX, 0, NULL);
+            ::LineTo(hdcMem, hotX, crosshair2);
+            ::MoveToEx(hdcMem, hotX, height - crosshair2, NULL);
+            ::LineTo(hdcMem, hotX, height);
+        }
+
+        // Draw brush or erase with color
+        if (is_rubber)
+            Erase(hdcMem, hotX, hotY, hotX, hotY, color, radius);
+        else
+            Brush(hdcMem, hotX, hotY, hotX, hotY, color, style, diameter);
+
+        ::SelectObject(hdcMem, hbmOld);
+    }
+
+    ::ReleaseDC(NULL, hdcScreen);
+    ::DeleteDC(hdcMem);
+
+    ICONINFO ii = { FALSE, hotX, hotY, hbmMask, hbmColor };
+    HCURSOR hCursor = (HCURSOR)::CreateIconIndirect(&ii);
+
+    ::DeleteObject(hbmMask);
+    ::DeleteObject(hbmColor);
+
+    return hCursor;
+}
+
+void CStyledCursor::SetStyle(BrushStyle style, INT radius, COLORREF color, BOOL is_rubber)
+{
+    if (m_hCursor && m_style == style && m_radius == radius && m_color == color &&
+        m_is_rubber == is_rubber)
+    {
+        return;
+    }
+
+    if (m_hCursor)
+        DestroyCursor(m_hCursor);
+
+    m_hCursor = CreateStyledCursor(style, radius, color, is_rubber);
+    m_style = style;
+    m_radius = radius;
+    m_color = color;
+    m_is_rubber = is_rubber;
+}
+
 CCanvasWindow::CCanvasWindow()
     : m_drawing(FALSE)
     , m_hitCanvasSizeBox(HIT_NONE)
@@ -641,6 +773,21 @@ LRESULT CCanvasWindow::OnSetCursor(UINT nMsg, WPARAM wParam, LPARAM lParam, BOOL
             case TOOL_AIRBRUSH:
                 ::SetCursor(::LoadCursorW(g_hinstExe, MAKEINTRESOURCEW(IDC_AIRBRUSH)));
                 break;
+            case TOOL_RUBBER:
+            {
+                m_hRubberCursor.SetStyle(BrushStyleSquare, toolsModel.GetRubberRadius(),
+                                         paletteModel.GetBgColor(), TRUE);
+                m_hRubberCursor.SetCursor();
+                break;
+            }
+            case TOOL_BRUSH:
+            {
+                m_hBrushCursor.SetStyle(toolsModel.GetBrushStyle(),
+                                        toolsModel.GetBrushWidth() / 2,
+                                        paletteModel.GetFgColor(), FALSE);
+                m_hBrushCursor.SetCursor();
+                break;
+            }
             default:
                 ::SetCursor(::LoadCursorW(NULL, (LPCWSTR)IDC_CROSS));
         }

base/applications/mspaint/canvas.h

@@ -3,10 +3,42 @@
  * LICENSE:    LGPL-2.0-or-later (https://spdx.org/licenses/LGPL-2.0-or-later)
  * PURPOSE:    Providing the canvas window class
  * COPYRIGHT:  Copyright 2015 Benedikt Freisen <[email protected]>
+ *             Copyright 2026 Katayama Hirofumi MZ <[email protected]>
  */
 
 #pragma once
 
+enum BrushStyle : int;
+
+class CStyledCursor
+{
+public:
+    ~CStyledCursor()
+    {
+        if (m_hCursor)
+            ::DestroyCursor(m_hCursor);
+    }
+
+    void SetStyle(BrushStyle style, INT radius, COLORREF color, BOOL is_rubber);
+
+    void SetCursor()
+    {
+        if (m_hCursor)
+            ::SetCursor(m_hCursor);
+    }
+
+    operator HCURSOR() const { return m_hCursor; }
+
+protected:
+    HCURSOR m_hCursor = NULL;
+    BrushStyle m_style;
+    INT m_radius = -1;
+    COLORREF m_color = CLR_INVALID;
+    BOOL m_is_rubber = FALSE;
+
+    static HCURSOR CreateStyledCursor(BrushStyle style, INT radius, COLORREF color, BOOL is_rubber);
+};
+
 class CCanvasWindow : public CWindowImpl<CCanvasWindow>
 {
 public:
@@ -56,6 +88,8 @@ public:
 
 protected:
     HITTEST m_hitCanvasSizeBox;
+    CStyledCursor m_hBrushCursor;
+    CStyledCursor m_hRubberCursor;
     POINT m_ptOrig; // The origin of drag start
     CRect m_rcResizing; // Resizing rectagle
 

base/applications/mspaint/toolsmodel.cpp

@@ -72,10 +72,17 @@ INT ToolsModel::GetBrushWidth() const
     return m_brushWidth;
 }
 
+void ToolsModel::SendSetCursor()
+{
+    canvasWindow.SendMessage(WM_SETCURSOR, (WPARAM)(HWND)canvasWindow,
+                             MAKELPARAM(HTCLIENT, WM_MOUSEMOVE));
+}
+
 void ToolsModel::SetBrushWidth(INT nBrushWidth)
 {
     m_brushWidth = nBrushWidth;
     NotifyToolSettingsChanged();
+    SendSetCursor();
     imageModel.NotifyImageChanged();
 }
 
@@ -128,6 +135,7 @@ BrushStyle ToolsModel::GetBrushStyle() const
 void ToolsModel::SetBrushStyle(BrushStyle nBrushStyle)
 {
     m_brushStyle = nBrushStyle;
+    SendSetCursor();
     NotifyToolSettingsChanged();
 }
 
@@ -199,6 +207,7 @@ int ToolsModel::GetRubberRadius() const
 void ToolsModel::SetRubberRadius(int nRubberRadius)
 {
     m_rubberRadius = nRubberRadius;
+    SendSetCursor();
     NotifyToolSettingsChanged();
 }
 

base/applications/mspaint/toolsmodel.h

@@ -28,7 +28,7 @@ enum TOOLTYPE
     TOOL_MAX = TOOL_RRECT,
 };
 
-enum BrushStyle
+enum BrushStyle : int
 {
     BrushStyleRound,
     BrushStyleSquare,
@@ -81,6 +81,7 @@ private:
     ToolBase *m_pToolObject;
 
     ToolBase *GetOrCreateTool(TOOLTYPE nTool);
+    void SendSetCursor();
 
 public:
     ToolsModel();