Add precision cursor support to pencil tool

Relates to #425

Still TODO is clone stamp tool, but it's a little more involved due to the "dual cursor" nature of the tool

Modules/Clonestamp.bas

@@ -972,7 +972,9 @@ Public Sub CommitBrushResults()
 
 End Sub
 
-'Render the current brush outline to the canvas, using the stored mouse coordinates as the brush's position
+'Render the current brush outline to the canvas, using the stored mouse coordinates as the brush's position.
+' (As of August 2022, Caps Lock can be used to toggle between precision and outline modes; this mimics Photoshop.
+'  See https://github.com/tannerhelland/PhotoDemon/issues/425 for details.)
 Public Sub RenderBrushOutline(ByRef targetCanvas As pdCanvas)
 
     'If a brush outline doesn't exist, create one now

Modules/PencilTool.bas

@@ -491,13 +491,19 @@ Public Sub RenderBrushOutline(ByRef targetCanvas As pdCanvas)
     Dim brushTooSmall As Boolean
     brushTooSmall = (onScreenSize < 7#)
 
+    'Like Photoshop, the CAPS LOCK key can be used to toggle between brush outlines and "precision" cursor mode.
+    ' In "precision" mode, we only draw a target cursor.
+    Dim renderInPrecisionMode As Boolean
+    renderInPrecisionMode = brushTooSmall Or OS.IsVirtualKeyDown_Synchronous(VK_CAPITAL, True)
+
     'Borrow a pair of UI pens from the main rendering module
     Dim innerPen As pd2DPen, outerPen As pd2DPen
     Drawing.BorrowCachedUIPens outerPen, innerPen
 
     'Create other required pd2D drawing tools (a surface)
     Dim cSurface As pd2DSurface
     Drawing2D.QuickCreateSurfaceFromDC cSurface, targetCanvas.hDC, True
+    cSurface.SetSurfacePixelOffset P2_PO_Normal
 
     'If the user is holding down the SHIFT key, paint a line between the end of the previous stroke and the current
     ' mouse position.  This helps communicate that shift+clicking will string together separate strokes.
@@ -514,23 +520,33 @@ Public Sub RenderBrushOutline(ByRef targetCanvas As pdCanvas)
     Else
 
         'Paint a target cursor - but *only* if the mouse is not currently down!
-        Dim crossLength As Single, outerCrossBorder As Single
+        Dim crossLength As Single, crossDistanceFromCenter As Single, outerCrossBorder As Single
         crossLength = 3!
-        outerCrossBorder = 0.5!
+        crossDistanceFromCenter = 4!
+        outerCrossBorder = 0.25!
+
+        If (Not m_MouseDown) And renderInPrecisionMode Then
 
-        If (Not m_MouseDown) Then
             outerPen.SetPenLineCap P2_LC_Round
             innerPen.SetPenLineCap P2_LC_Round
-            PD2D.DrawLineF cSurface, outerPen, cursX, cursY - crossLength - outerCrossBorder, cursX, cursY + crossLength + outerCrossBorder
-            PD2D.DrawLineF cSurface, outerPen, cursX - crossLength - outerCrossBorder, cursY, cursX + crossLength + outerCrossBorder, cursY
-            PD2D.DrawLineF cSurface, innerPen, cursX, cursY - crossLength, cursX, cursY + crossLength
-            PD2D.DrawLineF cSurface, innerPen, cursX - crossLength, cursY, cursX + crossLength, cursY
+
+            'Four "beneath" lines
+            PD2D.DrawLineF cSurface, outerPen, cursX, cursY - crossDistanceFromCenter + outerCrossBorder, cursX, cursY - crossDistanceFromCenter - crossLength - outerCrossBorder
+            PD2D.DrawLineF cSurface, outerPen, cursX, cursY + crossDistanceFromCenter - outerCrossBorder, cursX, cursY + crossDistanceFromCenter + crossLength + outerCrossBorder
+            PD2D.DrawLineF cSurface, outerPen, cursX - crossDistanceFromCenter + outerCrossBorder, cursY, cursX - crossDistanceFromCenter - crossLength - outerCrossBorder, cursY
+            PD2D.DrawLineF cSurface, outerPen, cursX + crossDistanceFromCenter - outerCrossBorder, cursY, cursX + crossDistanceFromCenter + crossLength + outerCrossBorder, cursY
+
+            'Four "above" lines
+            PD2D.DrawLineF cSurface, innerPen, cursX, cursY - crossDistanceFromCenter, cursX, cursY - crossDistanceFromCenter - crossLength
+            PD2D.DrawLineF cSurface, innerPen, cursX, cursY + crossDistanceFromCenter, cursX, cursY + crossDistanceFromCenter + crossLength
+            PD2D.DrawLineF cSurface, innerPen, cursX - crossDistanceFromCenter, cursY, cursX - crossDistanceFromCenter - crossLength, cursY
+            PD2D.DrawLineF cSurface, innerPen, cursX + crossDistanceFromCenter, cursY, cursX + crossDistanceFromCenter + crossLength, cursY
+
         End If
-
     End If
 
     'If size allows, render a transformed brush outline onto the canvas as well
-    If (Not brushTooSmall) Then
+    If (Not renderInPrecisionMode) Then
 
         'Get a copy of the current brush outline, transformed into position
         Dim copyOfBrushOutline As pd2DPath

PhotoDemon.vbp

@@ -513,7 +513,7 @@ Description="PhotoDemon Photo Editor"
 CompatibleMode="0"
 MajorVer=8
 MinorVer=9
-RevisionVer=1731
+RevisionVer=1732
 AutoIncrementVer=1
 ServerSupportFiles=0
 VersionComments="Copyright 2000-2022 Tanner Helland - photodemon.org"