Add posibility to scroll by-tiles using Ctrl+arrow keys (Paul Pridham idea).

+ Added ScrollCommand.

data/gui.xml

@@ -121,6 +121,28 @@
       <key command="ChangePen" shortcut="Minus Pad">
         <param name="change" value="decrement-size" />
       </key>
+
+      <!-- Scroll with cursor -->
+      <key command="Scroll" shortcut="Ctrl+Left">
+        <param name="direction" value="left" />
+        <param name="units" value="zoomed-tile-width" />
+        <param name="quantity" value="1" />
+      </key>
+      <key command="Scroll" shortcut="Ctrl+Right">
+        <param name="direction" value="right" />
+        <param name="units" value="zoomed-tile-width" />
+        <param name="quantity" value="1" />
+      </key>
+      <key command="Scroll" shortcut="Ctrl+Up">
+        <param name="direction" value="up" />
+        <param name="units" value="zoomed-tile-height" />
+        <param name="quantity" value="1" />
+      </key>
+      <key command="Scroll" shortcut="Ctrl+Down">
+        <param name="direction" value="down" />
+        <param name="units" value="zoomed-tile-height" />
+        <param name="quantity" value="1" />
+      </key>
     </commands>
 
     <!-- Keyboard shortcuts to select tools -->

src/CMakeLists.txt

@@ -223,6 +223,7 @@ add_library(aseprite-library
   commands/cmd_rotate_canvas.cpp
   commands/cmd_save_file.cpp
   commands/cmd_save_mask.cpp
+  commands/cmd_scroll.cpp
   commands/cmd_select_file.cpp
   commands/cmd_sprite_editor.cpp
   commands/cmd_sprite_properties.cpp

src/commands/cmd_scroll.cpp

@@ -0,0 +1,149 @@
+/* ASEPRITE
+ * Copyright (C) 2001-2012  David Capello
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include "config.h"
+
+#include "commands/command.h"
+#include "commands/params.h"
+#include "document_wrappers.h"
+#include "gui/view.h"
+#include "modules/editors.h"
+#include "settings/settings.h"
+#include "widgets/editor/editor.h"
+
+//////////////////////////////////////////////////////////////////////
+// scroll
+
+class ScrollCommand : public Command
+{
+public:
+  enum Direction { Left, Up, Right, Down, };
+  enum Units {
+    Pixel,
+    TileWidth,
+    TileHeight,
+    ZoomedPixel,
+    ZoomedTileWidth,
+    ZoomedTileHeight,
+    ViewportWidth,
+    ViewportHeight
+  };
+
+  ScrollCommand();
+  Command* clone() { return new ScrollCommand(*this); }
+
+protected:
+  void onLoadParams(Params* params);
+  bool onEnabled(Context* context);
+  void onExecute(Context* context);
+
+private:
+  Direction m_direction;
+  Units m_units;
+  int m_quantity;
+};
+
+ScrollCommand::ScrollCommand()
+  : Command("Scroll",
+            "Scroll",
+            CmdUIOnlyFlag)
+{
+}
+
+void ScrollCommand::onLoadParams(Params* params)
+{
+  std::string direction = params->get("direction");
+  if (direction == "left") m_direction = Left;
+  else if (direction == "right") m_direction = Right;
+  else if (direction == "up") m_direction = Up;
+  else if (direction == "down") m_direction = Down;
+
+  std::string units = params->get("units");
+  if (units == "pixel") m_units = Pixel;
+  else if (units == "tile-width") m_units = TileWidth;
+  else if (units == "tile-height") m_units = TileHeight;
+  else if (units == "zoomed-pixel") m_units = ZoomedPixel;
+  else if (units == "zoomed-tile-width") m_units = ZoomedTileWidth;
+  else if (units == "zoomed-tile-height") m_units = ZoomedTileHeight;
+  else if (units == "viewport-width") m_units = ViewportWidth;
+  else if (units == "viewport-height") m_units = ViewportHeight;
+
+  int quantity = params->get_as<int>("quantity");
+  m_quantity = std::max<int>(1, quantity);
+}
+
+bool ScrollCommand::onEnabled(Context* context)
+{
+  ActiveDocumentWriter document(context);
+  return document != NULL;
+}
+
+void ScrollCommand::onExecute(Context* context)
+{
+  View* view = View::getView(current_editor);
+  gfx::Rect vp = view->getViewportBounds();
+  gfx::Point scroll = view->getViewScroll();
+  gfx::Rect gridBounds = context->getSettings()->getGridBounds();
+  int dx = 0;
+  int dy = 0;
+  int pixels = 0;
+
+  switch (m_units) {
+    case Pixel:
+      pixels = 1;
+      break;
+    case TileWidth:
+      pixels = gridBounds.w;
+      break;
+    case TileHeight:
+      pixels = gridBounds.h;
+      break;
+    case ZoomedPixel:
+      pixels = 1 << current_editor->getZoom();
+      break;
+    case ZoomedTileWidth:
+      pixels = gridBounds.w << current_editor->getZoom();
+      break;
+    case ZoomedTileHeight:
+      pixels = gridBounds.h << current_editor->getZoom();
+      break;
+    case ViewportWidth:
+      pixels = vp.h;
+      break;
+    case ViewportHeight:
+      pixels = vp.w;
+      break;
+  }
+
+  switch (m_direction) {
+    case Left:  dx = -m_quantity * pixels; break;
+    case Right: dx = +m_quantity * pixels; break;
+    case Up:    dy = -m_quantity * pixels; break;
+    case Down:  dy = +m_quantity * pixels; break;
+  }
+
+  current_editor->setEditorScroll(scroll.x+dx, scroll.y+dy, true);
+}
+
+//////////////////////////////////////////////////////////////////////
+// CommandFactory
+
+Command* CommandFactory::createScrollCommand()
+{
+  return new ScrollCommand;
+}

src/commands/commands_list.h

@@ -95,6 +95,7 @@ FOR_EACH_COMMAND(SaveFile)
 FOR_EACH_COMMAND(SaveFileAs)
 FOR_EACH_COMMAND(SaveFileCopyAs)
 FOR_EACH_COMMAND(SaveMask)
+FOR_EACH_COMMAND(Scroll)
 FOR_EACH_COMMAND(SelectFile)
 FOR_EACH_COMMAND(ShowGrid)
 FOR_EACH_COMMAND(SnapToGrid)