Add she::LockedSurface::scrollTo() so we can specialize it in the Skia port

src/she/alleg4/surface.h

@@ -349,6 +349,13 @@ namespace she {
         width, height);
     }
 
+    void scrollTo(const gfx::Rect& rc, int dx, int dy) override {
+      blit(m_bmp, m_bmp,
+        rc.x, rc.y,
+        rc.x+dx, rc.y+dy,
+        rc.w, rc.h);
+    }
+
     void drawSurface(const LockedSurface* src, int dstx, int dsty) override {
       draw_sprite(m_bmp, static_cast<const Alleg4Surface*>(src)->m_bmp, dstx, dsty);
     }

src/she/locked_surface.h

@@ -44,6 +44,7 @@ namespace she {
     virtual void fillRect(gfx::Color color, const gfx::Rect& rc) = 0;
 
     virtual void blitTo(LockedSurface* dest, int srcx, int srcy, int dstx, int dsty, int width, int height) const = 0;
+    virtual void scrollTo(const gfx::Rect& rc, int dx, int dy) = 0;
     virtual void drawSurface(const LockedSurface* src, int dstx, int dsty) = 0;
     virtual void drawRgbaSurface(const LockedSurface* src, int dstx, int dsty) = 0;
     virtual void drawColoredRgbaSurface(const LockedSurface* src, gfx::Color fg, gfx::Color bg, const gfx::Clip& clip) = 0;

src/she/skia/skia_surface.h

@@ -258,6 +258,39 @@ public:
     ((SkiaSurface*)dest)->m_canvas->drawBitmapRectToRect(m_bitmap, &srcRect, dstRect, &paint);
   }
 
+  void scrollTo(const gfx::Rect& rc, int dx, int dy) override {
+    int w = m_bitmap.width();
+    int h = m_bitmap.height();
+    gfx::Clip clip(rc.x+dx, rc.y+dy, rc);
+    if (!clip.clip(w, h, w, h))
+      return;
+
+    int bytesPerPixel = m_bitmap.bytesPerPixel();
+    int rowBytes = (int)m_bitmap.rowBytes();
+    int rowDelta;
+
+    if (dy > 0) {
+      clip.src.y += clip.size.h-1;
+      clip.dst.y += clip.size.h-1;
+      rowDelta = -rowBytes;
+    }
+    else
+      rowDelta = rowBytes;
+
+    char* dst = (char*)m_bitmap.getPixels();
+    const char* src = dst;
+    dst += rowBytes*clip.dst.y + bytesPerPixel*clip.dst.x;
+    src += rowBytes*clip.src.y + bytesPerPixel*clip.src.x;
+    w = bytesPerPixel*clip.size.w;
+    h = clip.size.h;
+
+    while (--h >= 0) {
+      memmove(dst, src, w);
+      dst += rowDelta;
+      src += rowDelta;
+    }
+  }
+
   void drawSurface(const LockedSurface* src, int dstx, int dsty) override {
     gfx::Clip clip(dstx, dsty, 0, 0,
       ((SkiaSurface*)src)->m_bitmap.width(),

src/ui/move_region.cpp

@@ -22,12 +22,8 @@ namespace ui {
 
 using namespace gfx;
 
-void move_region(const Region& region, int dx, int dy)
+void move_region(Manager* manager, const Region& region, int dx, int dy)
 {
-  ASSERT(Manager::getDefault());
-  if (!Manager::getDefault())
-    return;
-
   she::System* system = she::instance();
   she::Display* display = Manager::getDefault()->getDisplay();
   ASSERT(display);
@@ -40,7 +36,7 @@ void move_region(const Region& region, int dx, int dy)
   // Blit directly screen to screen.
   if (nrects == 1) {
     Rect rc = region[0];
-    lock->blitTo(lock, rc.x, rc.y, rc.x+dx, rc.y+dy, rc.w, rc.h);
+    lock->scrollTo(rc, dx, dy);
   }
   // Blit saving areas and copy them.
   else if (nrects > 1) {

src/ui/move_region.h

@@ -1,5 +1,5 @@
 // Aseprite UI Library
-// Copyright (C) 2001-2014  David Capello
+// Copyright (C) 2001-2015  David Capello
 //
 // This file is released under the terms of the MIT license.
 // Read LICENSE.txt for more information.
@@ -10,9 +10,11 @@
 
 #include "gfx/region.h"
 
-namespace ui { // TODO all these functions are deprecated and must be replaced by Graphics methods.
+namespace ui {
 
-  void move_region(const gfx::Region& region, int dx, int dy);
+  class Manager;
+
+  void move_region(Manager* manager, const gfx::Region& region, int dx, int dy);
 
 } // namespace ui
 

src/ui/widget.cpp

@@ -1068,7 +1068,7 @@ void Widget::scrollRegion(const Region& region, const Point& delta)
   reg2.offset(-delta);
 
   // Move screen pixels
-  ui::move_region(reg2, delta.x, delta.y);
+  ui::move_region(getManager(), reg2, delta.x, delta.y);
 
   reg2.offset(delta);
 

src/ui/window.cpp

@@ -577,7 +577,7 @@ void Window::moveWindow(const gfx::Rect& rect, bool use_blit)
     {
       IntersectClip clip(&g, man_pos);
       if (clip) {
-        ui::move_region(moveableRegion, dx, dy);
+        ui::move_region(manager, moveableRegion, dx, dy);
       }
     }
     show_mouse_cursor();