From f44b12f14b5f84844fb302bdf6c0dd9128681b27 Mon Sep 17 00:00:00 2001
From: gambas <g4mba5@gmail.com>
Date: Tue, 9 Jul 2019 19:43:15 +0200
Subject: [PATCH] DocumentView: Fix some bugs and add ShowPage and Desaturate
 properties.

[GB.FORM]
* NEW: DocumentView: The default background color is now a mix of the default text foreground and background colors.
* BUG: DocumentView: Use Paint.Begin() instead of Draw.Begin(), so that preview uses anti-aliasing.
* BUG: DocumentView: Fix some cases of page drawing not correctly triggered.
* NEW: DocumentView: ShowPage is new property that displays the current page and the number of pages inside the preview.
* NEW: DocumentView: Desaturate is a new property that desaturates the preview. It's slow when the zoom is huge.
* NEW: DocumentView: Allow zoom up to 800%.
---
 .../.src/DocumentView/DocumentView.class      | 82 +++++++++++++++----
 1 file changed, 66 insertions(+), 16 deletions(-)

diff --git a/comp/src/gb.form/.src/DocumentView/DocumentView.class b/comp/src/gb.form/.src/DocumentView/DocumentView.class
index 9624af49a..a8958a7fe 100644
--- a/comp/src/gb.form/.src/DocumentView/DocumentView.class
+++ b/comp/src/gb.form/.src/DocumentView/DocumentView.class
@@ -3,11 +3,10 @@
 Export
 Inherits UserControl
 
-Public Const _Properties As String = "*,Border,Arrangement{Arrange.Row;Column;Vertical;Horizontal;Fill}=Row,Padding=10,Spacing=10,Column,AutoCenter,ShowShadow"
+Public Const _Properties As String = "*,Border,Arrangement{Arrange.Row;Column;Vertical;Horizontal;Fill}=Row,Padding=10,Spacing=10,Column,AutoCenter,ShowShadow,ShowPage"
 Public Const _Group As String = "View"
 Public Const _Similar As String = "GridView"
 
-Public _ShowPageNumber As Boolean
 Public Enum Portrait, Paysage
 'Public Enum None, PagesWidth, PageHeight
 Property DocWidth, PageWidth As Integer
@@ -21,11 +20,13 @@ Property Arrangement As Integer
 Property Padding As Integer 
 Property Spacing As Integer
 Property ShowShadow As Boolean
+Property ShowPage As Boolean
 Property Read Item As _DocumentItem
 Property Read FirstVisibleDocument As Integer
 Property Read LastVisibleDocument As Integer
 Property AutoCenter As Boolean
 Property Border As Boolean
+Property Desaturate As Boolean
 
 Private $bAutoCenter As Boolean
 Private $iColumn As Integer 
@@ -72,17 +73,19 @@ Private $iSX As Integer
 Private $iSY As Integer
 Private $MX As Integer
 Private $MY As Integer
+Private $bShowPage As Boolean
 Private $hObs As Observer
 
 Event Layout(Page As Integer)
 Event Draw(Page As Integer, Width As Integer, Height As Integer)
 Event Finished
 Event Zoom
+Private $bDesaturate As Boolean
 
 Public Sub _new()
   
   $hView = New ScrollArea(Me) As "View"
-  $hView.Background = Color.DarkGray
+  $hView.Background = Color.Merge(Color.TextBackground, Color.TextForeground)
   '$tmrLoad.Delay = 100
   Me.Proxy = $hView
   $hDocItem = New _DocumentItem As "Doc"
@@ -114,12 +117,13 @@ Public Sub tmrLoad_Timer()
   'Raise Layout(iPage)
   
   hImg = New Image(iDocWidth * $fZoom, iDocHeight * $fZoom, Color.White)
-  Draw.Begin(hImg)
+  Paint.Begin(hImg)
   'Paint.Scale($fZoom, $fZoom)
   Raise Draw(iPage, iDocWidth * $fZoom, iDocHeight * $fZoom)
-  Draw.End
+  Paint.End
   $colImage[iPage] = hImg
   $aImageLoaded.Add(iPage)
+  $tmrLoad.Trigger
   $tmrRefresh.Trigger
   
 End
@@ -127,8 +131,12 @@ End
 Public Sub View_Draw()
   
   Dim i, j, k As Integer
+  Dim sText As String
+  Dim W As Integer
+  Dim D As Integer
   
   If $iCount = 0 Then Return 
+  
   Select Case $iArrangement
     Case Arrange.Horizontal
       k = $iFirstVisibleDocument
@@ -145,8 +153,8 @@ Public Sub View_Draw()
           DrawDoc(k, i, j)
           
           Inc k
-          If k > $iLastVisibleDocument Then Return
-          If k >= $iCount Then Return
+          If k > $iLastVisibleDocument Then Goto SHOW_PAGE
+          If k >= $iCount Then Goto SHOW_PAGE
         Next
       Next
       
@@ -157,8 +165,8 @@ Public Sub View_Draw()
         For i = 0 To $iNbreLines - 1
           DrawDoc(k, i, j)
           Inc k
-          If K > $iLastVisibleDocument Then Return
-          If K >= $iCount Then Return
+          If K > $iLastVisibleDocument Then Goto SHOW_PAGE
+          If K >= $iCount Then Goto SHOW_PAGE
         Next
       Next
       
@@ -177,12 +185,29 @@ Public Sub View_Draw()
       Next
   End Select
   
+SHOW_PAGE:
+
+  If $bShowPage Then
+    
+    D = Desktop.Scale
+    sText = CStr($iFirstVisibleDocument + 1) & " / " & CStr($iCount)
+    W = Paint.Font.TextWidth(sText) + D * 2
+    Paint.FillRect(Paint.W - W - D, D, W, Paint.Font.H + D, Color.SetAlpha(Color.TextForeground, 128))
+    Paint.Background = Color.SetAlpha(Color.TextBackground, 128)
+    Paint.DrawText(sText, Paint.W - W - D + 1, D, W, Paint.Font.H + D, Align.Center)
+    Paint.Background = Color.TextBackground
+    Paint.DrawText(sText, Paint.W - W - D, D, W, Paint.Font.H + D, Align.Center)
+    
+  Endif
+  
 End
 
 Private Sub DrawDoc(Page As Integer, iRow As Integer, iCol As Integer)
   
   Dim iDocX, iDocY As Integer
   Dim fShad As Float = $fZoom * ($iSpacing / 4)
+  Dim hImage As Image
+  
   'Dim fFullContentWidth As Float
 
   If $colLayout.Exist(Page) Then
@@ -225,7 +250,9 @@ Private Sub DrawDoc(Page As Integer, iRow As Integer, iCol As Integer)
   Endif
   
   If $colImage.Exist(Page) Then
-    Paint.DrawImage($colImage[Page], iDocX, iDocY, $fScaledDocWidth, $fScaledDocHeight)
+    hImage = $colImage[Page]
+    If $bDesaturate Then hImage = hImage.Copy().Desaturate()
+    Paint.DrawImage(hImage, iDocX, iDocY, $fScaledDocWidth, $fScaledDocHeight)
     Paint.Rectangle(iDocX, iDocY, $fScaledDocWidth, $fScaledDocHeight)
     Paint.Brush = Paint.Color(Color.Black)
     Paint.Stroke
@@ -243,11 +270,6 @@ Private Sub DrawDoc(Page As Integer, iRow As Integer, iCol As Integer)
     Paint.Fill()
   Endif
   
-  If _ShowPageNumber Then
-    Paint.Font.Grade = 20 * $fZoom
-    Paint.DrawText(Page, iDocX, iDocY, $fScaledDocWidth, $fScaledDocHeight, Align.Center)
-  Endif
-  
 End
 
 Private Sub RefreshLayoutNeeds()
@@ -540,7 +562,7 @@ Private Sub Zoom_Write(Value As Float)
   Select Case $iArrangement
     Case Arrange.None, Arrange.Row, Arrange.Column, Arrange.LeftRight, Arrange.TopBottom
       
-      SetZoom(Min(Max(Value, 0.1), 4))
+      SetZoom(Min(Max(Value, 0.1), 8))
       '$iArrangement = None
       '$fZoom = $fZoom
       'just refresh image in the cache don't clear them
@@ -994,3 +1016,31 @@ Private Sub Border_Write(Value As Boolean)
   $hView.Border = Value
 
 End
+
+Private Function ShowPage_Read() As Boolean
+
+  Return $bShowPage
+
+End
+
+Private Sub ShowPage_Write(Value As Boolean)
+
+  If $bShowPage = Value Then Return
+  $bShowPage = Value
+  $hView.Refresh
+
+End
+
+Private Function Desaturate_Read() As Boolean
+
+  Return $bDesaturate
+
+End
+
+Private Sub Desaturate_Write(Value As Boolean)
+
+  If $bDesaturate = Value Then Return
+  $bDesaturate = Value
+  $hView.refresh
+
+End