3 files changed, 44 insertions, 8 deletions

diff --git a/engines/pegasus/elements.cpp b/engines/pegasus/elements.cpp
index 695a6e54b8..f9881e7aaf 100644
--- a/engines/pegasus/elements.cpp
+++ b/engines/pegasus/elements.cpp
@@ -163,7 +163,7 @@ DropHighlight::DropHighlight(const tDisplayElementID id) : DisplayElement(id) {
 }
 
 void DropHighlight::draw(const Common::Rect &) {
-	Graphics::Surface *screen = g_system->lockScreen();
+	Graphics::Surface *screen = ((PegasusEngine *)g_engine)->_gfx->getWorkArea();
 
 	// Since this is only used in two different ways, I'm only
 	// going to implement it in those two ways. Deal with it.
@@ -181,8 +181,6 @@ void DropHighlight::draw(const Common::Rect &) {
 		screen->vLine(rect.left - 1, rect.top + 1, rect.bottom - 2, _highlightColor);
 		screen->vLine(rect.right, rect.top + 1, rect.bottom - 2, _highlightColor);
 	}
-
-	g_system->unlockScreen();
 }
 
 EnergyBar::EnergyBar(const tDisplayElementID id) : DisplayElement(id) {
@@ -225,11 +223,8 @@ void EnergyBar::draw(const Common::Rect &r) {
 	Common::Rect levelRect;
 	calcLevelRect(levelRect);
 
-	if (r.intersects(levelRect)) {
-		Graphics::Surface *screen = g_system->lockScreen();
-		screen->fillRect(levelRect, _barColor);
-		g_system->lockScreen();
-	}
+	if (r.intersects(levelRect))
+		((PegasusEngine *)g_engine)->_gfx->getWorkArea()->fillRect(levelRect, _barColor);
 }
 
 void EnergyBar::calcLevelRect(Common::Rect &r) const {
diff --git a/engines/pegasus/graphics.cpp b/engines/pegasus/graphics.cpp
index abff3df15a..d5d6350ca3 100644
--- a/engines/pegasus/graphics.cpp
+++ b/engines/pegasus/graphics.cpp
@@ -35,6 +35,9 @@ namespace Pegasus {
 GraphicsManager::GraphicsManager(PegasusEngine *vm) : _vm(vm) {
 	initGraphics(640, 480, true, NULL);
 
+	if (_vm->_system->getScreenFormat().bytesPerPixel == 1)
+		error("No true color mode available");
+
 	// Old
 	_pictDecoder = new Graphics::PictDecoder(_vm->_system->getScreenFormat());
 
@@ -45,6 +48,7 @@ GraphicsManager::GraphicsManager(PegasusEngine *vm) : _vm(vm) {
 	_backLayer = kMinAvailableOrder;
 	_frontLayer = kMaxAvailableOrder;
 	_firstDisplayElement = _lastDisplayElement = 0;
+	_workArea.create(640, 480, _vm->_system->getScreenFormat());
 }
 	
 GraphicsManager::~GraphicsManager() {
@@ -57,6 +61,9 @@ GraphicsManager::~GraphicsManager() {
 			delete _cache[i].surface;
 		}
 	}
+
+	// New
+	_workArea.free();
 }
 
 Graphics::Surface *GraphicsManager::decodeImage(const Common::String &filename) {
@@ -272,5 +279,35 @@ void GraphicsManager::removeDisplayElement(DisplayElement *oldElement) {
 	oldElement->_nextElement = 0;
 	oldElement->_elementIsDisplaying = false;
 }
+
+void GraphicsManager::updateDisplay() {
+	// TODO: Check for cursor move/change
+
+	bool screenDirty = false;
+
+	if (!_dirtyRect.isEmpty()) {
+		for (DisplayElement *runner = _firstDisplayElement; runner != 0; runner = runner->_nextElement) {
+			Common::Rect bounds;
+			runner->getBounds(bounds);
+
+			// TODO: Better logic; it does a bit more work than it probably needs to
+			// but it should work fine for now.
+			if (bounds.intersects(_dirtyRect) && runner->validToDraw(_backLayer, _frontLayer))
+				runner->draw(bounds);
+		}
+
+		// Copy only the dirty rect to the screen
+		g_system->copyRectToScreen((byte *)_workArea.pixels, _workArea.pitch, _dirtyRect.left, _dirtyRect.top, _dirtyRect.width(), _dirtyRect.height());
+
+		// Mark the screen as dirty
+		screenDirty = true;
+
+		// Clear the dirty rect
+		_dirtyRect = Common::Rect();
+	}
+
+	if (screenDirty)
+		g_system->updateScreen();
+}
 	
 } // End of namespace Pegasus
diff --git a/engines/pegasus/graphics.h b/engines/pegasus/graphics.h
index d8919e5b5c..d4f9628fa1 100644
--- a/engines/pegasus/graphics.h
+++ b/engines/pegasus/graphics.h
@@ -66,6 +66,9 @@ public:
 	void invalRect(const Common::Rect &rect);
 	tDisplayOrder getBackOfActiveLayer() const { return _backLayer; }
 	tDisplayOrder getFrontOfActiveLayer() const { return _frontLayer; }
+	void updateDisplay();
+	Graphics::Surface *getWorkArea() { return &_workArea; }
+
 private:		
 	PegasusEngine *_vm;
 
@@ -79,6 +82,7 @@ private:
 	Common::Rect _dirtyRect;
 	tDisplayOrder _backLayer, _frontLayer;
 	DisplayElement *_firstDisplayElement, *_lastDisplayElement;
+	Graphics::Surface _workArea;
 };
 
 } // End of namespace Pegasus