From e015151f8948468bd9d75c1e85fd0690e9f3cd21 Mon Sep 17 00:00:00 2001
From: Ben Olden-Cooligan <ben.cyanfish@gmail.com>
Date: Thu, 8 Jun 2017 11:53:12 -0400
Subject: [PATCH] Add new twain impl option for MemXfer

---
 .../Lang/Resources/SettingsResources.Designer.cs      |  9 +++++++++
 NAPS2.Core/Lang/Resources/SettingsResources.resx      |  3 +++
 NAPS2.Core/Scan/ScanProfile.cs                        |  2 ++
 NAPS2.Core/Scan/Twain/TwainWrapper.cs                 | 11 +++++++----
 NAPS2.Core/WinForms/FAdvancedScanSettings.cs          |  1 +
 5 files changed, 22 insertions(+), 4 deletions(-)

diff --git a/NAPS2.Core/Lang/Resources/SettingsResources.Designer.cs b/NAPS2.Core/Lang/Resources/SettingsResources.Designer.cs
index a50c27495..3246abcc1 100644
--- a/NAPS2.Core/Lang/Resources/SettingsResources.Designer.cs
+++ b/NAPS2.Core/Lang/Resources/SettingsResources.Designer.cs
@@ -366,6 +366,15 @@ namespace NAPS2.Lang.Resources {
             }
         }
         
+        /// <summary>
+        ///   Looks up a localized string similar to Alternative Transfer.
+        /// </summary>
+        internal static string TwainImpl_MemXfer {
+            get {
+                return ResourceManager.GetString("TwainImpl_MemXfer", resourceCulture);
+            }
+        }
+        
         /// <summary>
         ///   Looks up a localized string similar to Old DSM.
         /// </summary>
diff --git a/NAPS2.Core/Lang/Resources/SettingsResources.resx b/NAPS2.Core/Lang/Resources/SettingsResources.resx
index 96ea0f744..e5a0e50e0 100644
--- a/NAPS2.Core/Lang/Resources/SettingsResources.resx
+++ b/NAPS2.Core/Lang/Resources/SettingsResources.resx
@@ -219,6 +219,9 @@
   <data name="TwainImpl_Legacy" xml:space="preserve">
     <value>Legacy (native UI only)</value>
   </data>
+  <data name="TwainImpl_MemXfer" xml:space="preserve">
+    <value>Alternative Transfer</value>
+  </data>
   <data name="TwainImpl_OldDsm" xml:space="preserve">
     <value>Old DSM</value>
   </data>
diff --git a/NAPS2.Core/Scan/ScanProfile.cs b/NAPS2.Core/Scan/ScanProfile.cs
index e6507a793..5bbbdc32c 100644
--- a/NAPS2.Core/Scan/ScanProfile.cs
+++ b/NAPS2.Core/Scan/ScanProfile.cs
@@ -139,6 +139,8 @@ namespace NAPS2.Scan
     {
         [LocalizedDescription(typeof(SettingsResources), "TwainImpl_Default")]
         Default,
+        [LocalizedDescription(typeof(SettingsResources), "TwainImpl_MemXfer")]
+        MemXfer,
         [LocalizedDescription(typeof(SettingsResources), "TwainImpl_OldDsm")]
         OldDsm,
         [LocalizedDescription(typeof(SettingsResources), "TwainImpl_Legacy")]
diff --git a/NAPS2.Core/Scan/Twain/TwainWrapper.cs b/NAPS2.Core/Scan/Twain/TwainWrapper.cs
index 62075e0bf..5a9da322d 100644
--- a/NAPS2.Core/Scan/Twain/TwainWrapper.cs
+++ b/NAPS2.Core/Scan/Twain/TwainWrapper.cs
@@ -85,8 +85,6 @@ namespace NAPS2.Scan.Twain
 
             int pageNumber = 0;
 
-            bool useMemXfer = false;
-
             session.TransferReady += (sender, eventArgs) =>
             {
                 Debug.WriteLine("NAPS2.TW - TransferReady");
@@ -101,7 +99,7 @@ namespace NAPS2.Scan.Twain
                 {
                     Debug.WriteLine("NAPS2.TW - DataTransferred");
                     pageNumber++;
-                    using (var output = useMemXfer
+                    using (var output = scanProfile.TwainImpl == TwainImpl.MemXfer
                                         ? GetBitmapFromMemXFer(eventArgs.MemoryData, eventArgs.ImageInfo)
                                         : Image.FromStream(eventArgs.GetNativeImageStream()))
                     {
@@ -198,7 +196,6 @@ namespace NAPS2.Scan.Twain
                         return;
                     }
                     ConfigureDS(ds, scanProfile, scanParams);
-                    useMemXfer = ds.Capabilities.ICapXferMech.GetCurrent() == XferMech.Memory;
                     var ui = scanProfile.UseNativeUI ? SourceEnableMode.ShowUI : SourceEnableMode.NoUI;
                     Debug.WriteLine("NAPS2.TW - Enabling DS");
                     rc = ds.Enable(ui, true, twainForm.Handle);
@@ -310,6 +307,12 @@ namespace NAPS2.Scan.Twain
                 return;
             }
 
+            // Transfer Mode
+            if (scanProfile.TwainImpl == TwainImpl.MemXfer)
+            {
+                ds.Capabilities.ICapXferMech.SetValue(XferMech.Memory);
+            }
+
             // Paper Source
             switch (scanProfile.PaperSource)
             {
diff --git a/NAPS2.Core/WinForms/FAdvancedScanSettings.cs b/NAPS2.Core/WinForms/FAdvancedScanSettings.cs
index 24afbf335..ae8f576ed 100644
--- a/NAPS2.Core/WinForms/FAdvancedScanSettings.cs
+++ b/NAPS2.Core/WinForms/FAdvancedScanSettings.cs
@@ -19,6 +19,7 @@ namespace NAPS2.WinForms
 
             cmbTwainImpl.Format += (sender, e) => e.Value = ((Enum) e.ListItem).Description();
             cmbTwainImpl.Items.Add(TwainImpl.Default);
+            cmbTwainImpl.Items.Add(TwainImpl.MemXfer);
             cmbTwainImpl.Items.Add(TwainImpl.OldDsm);
             cmbTwainImpl.Items.Add(TwainImpl.Legacy);
             if (Environment.Is64BitProcess)