implemented cursor support in the DisplayDriverPainter

git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@12107 a95241bf-73f2-0310-859d-f6bbb57e9c96

src/servers/app/drawing/DisplayDriver.cpp

@@ -38,8 +38,7 @@
 	\brief Sets up internal variables needed by all DisplayDriver subclasses
 */
 DisplayDriver::DisplayDriver()
-	: fCursorHandler(this),
-	  fDPMSState(B_DPMS_ON),
+	: fDPMSState(B_DPMS_ON),
 	  fDPMSCaps(B_DPMS_ON)
 {
 	fDisplayMode.virtual_width = 640;
@@ -68,7 +67,7 @@ DisplayDriver::~DisplayDriver()
 bool
 DisplayDriver::Initialize()
 {
-	fCursorHandler.SetCursor(new ServerCursor(default_cursor_data));
+	SetCursor(new ServerCursor(default_cursor_data));
 	return true;
 }
 
@@ -83,127 +82,6 @@ DisplayDriver::Shutdown()
 {
 }
 
-/*!
-	\brief Hides the cursor.
-	
-	Hide calls are not nestable, unlike that of the BApplication class. Subclasses should
-	call _SetCursorHidden(true) somewhere within this function to ensure that data is
-	maintained accurately. Subclasses must include a call to DisplayDriver::HideCursor
-	for proper state tracking.
-*/
-void
-DisplayDriver::HideCursor()
-{
-	Lock();
-	fCursorHandler.Hide();	
-	Unlock();
-}
-
-/*!
-	\brief Returns whether the cursor is visible or not.
-	\return true if hidden or obscured, false if not.
-
-*/
-bool
-DisplayDriver::IsCursorHidden()
-{
-	Lock();
-	bool value = fCursorHandler.IsHidden();
-	Unlock();
-
-	return value;
-}
-
-/*!
-	\brief Moves the cursor to the given point.
-
-	The coordinates passed to MoveCursorTo are guaranteed to be within the frame buffer's
-	range, but the cursor data itself will need to be clipped. A check to see if the 
-	cursor is obscured should be made and if so, a call to _SetCursorObscured(false) 
-	should be made the cursor in addition to displaying at the passed coordinates.
-*/
-void
-DisplayDriver::MoveCursorTo(const float &x, const float &y)
-{
-	Lock();
-	fCursorHandler.MoveTo(BPoint(x, y));
-	Unlock();
-}
-
-/*!
-	\brief Shows the cursor.
-	
-	Show calls are not nestable, unlike that of the BApplication class. Subclasses should
-	call _SetCursorHidden(false) somewhere within this function to ensure that data is
-	maintained accurately. Subclasses must call DisplayDriver::ShowCursor at some point
-	to ensure proper state tracking.
-*/
-void
-DisplayDriver::ShowCursor()
-{
-	Lock();
-	fCursorHandler.Show();
-	Unlock();
-}
-
-/*!
-	\brief Obscures the cursor.
-	
-	Obscure calls are not nestable. Subclasses should call DisplayDriver::ObscureCursor
-	somewhere within this function to ensure that data is maintained accurately. A check
-	will be made by the system before the next MoveCursorTo call to show the cursor if
-	it is obscured.
-*/
-void
-DisplayDriver::ObscureCursor()
-{
-	Lock();
-	fCursorHandler.Obscure();	
-	Unlock();
-
-}
-
-/*!
-	\brief Changes the cursor.
-	\param cursor The new cursor. Guaranteed to be non-NULL.
-	
-	The driver does not take ownership of the given cursor. Subclasses should make
-	a copy of the cursor passed to it. The default version of this function hides the
-	cursory, replaces it, and shows the cursor if previously visible.
-*/
-void
-DisplayDriver::SetCursor(ServerCursor *cursor)
-{
-	Lock();
-	fCursorHandler.SetCursor(cursor);
-	Unlock();
-}
-
-//! Returns the cursor's current position
-BPoint
-DisplayDriver::GetCursorPosition()
-{
-	Lock();
-	BPoint pos = fCursorHandler.GetPosition();
-	Unlock();
-	
-	return pos;
-}
-
-/*!
-	\brief Returns whether or not the cursor is currently obscured
-	\return True if obscured, false if not.
-*/
-bool
-DisplayDriver::IsCursorObscured(bool state)
-{
-	Lock();
-	bool obscured = fCursorHandler.IsObscured();
-	Unlock();
-	
-	return obscured;
-}
-
 // Protected Internal Functions
 /*
 	\brief Sets the screen mode to specified resolution and color depth.

src/servers/app/drawing/DisplayDriverImpl.cpp

@@ -51,7 +51,8 @@ static Blitter blitter;
 */
 DisplayDriverImpl::DisplayDriverImpl()
 	: DisplayDriver(),
-	  fLocker("DisplayDriver lock")
+	  fLocker("DisplayDriver lock"),
+	  fCursorHandler(this)
 {
 }
 
@@ -2272,6 +2273,127 @@ void DisplayDriverImpl::GetTruncatedStrings(const char **instrings,const int32 &
 	// TODO: Implement DisplayDriverImpl::GetTruncatedStrings
 }
 
+/*!
+	\brief Hides the cursor.
+	
+	Hide calls are not nestable, unlike that of the BApplication class. Subclasses should
+	call _SetCursorHidden(true) somewhere within this function to ensure that data is
+	maintained accurately. Subclasses must include a call to DisplayDriver::HideCursor
+	for proper state tracking.
+*/
+void
+DisplayDriverImpl::HideCursor()
+{
+	Lock();
+	fCursorHandler.Hide();	
+	Unlock();
+}
+
+/*!
+	\brief Returns whether the cursor is visible or not.
+	\return true if hidden or obscured, false if not.
+
+*/
+bool
+DisplayDriverImpl::IsCursorHidden()
+{
+	Lock();
+	bool value = fCursorHandler.IsHidden();
+	Unlock();
+
+	return value;
+}
+
+/*!
+	\brief Moves the cursor to the given point.
+
+	The coordinates passed to MoveCursorTo are guaranteed to be within the frame buffer's
+	range, but the cursor data itself will need to be clipped. A check to see if the 
+	cursor is obscured should be made and if so, a call to _SetCursorObscured(false) 
+	should be made the cursor in addition to displaying at the passed coordinates.
+*/
+void
+DisplayDriverImpl::MoveCursorTo(const float &x, const float &y)
+{
+	Lock();
+	fCursorHandler.MoveTo(BPoint(x, y));
+	Unlock();
+}
+
+/*!
+	\brief Shows the cursor.
+	
+	Show calls are not nestable, unlike that of the BApplication class. Subclasses should
+	call _SetCursorHidden(false) somewhere within this function to ensure that data is
+	maintained accurately. Subclasses must call DisplayDriver::ShowCursor at some point
+	to ensure proper state tracking.
+*/
+void
+DisplayDriverImpl::ShowCursor()
+{
+	Lock();
+	fCursorHandler.Show();
+	Unlock();
+}
+
+/*!
+	\brief Obscures the cursor.
+	
+	Obscure calls are not nestable. Subclasses should call DisplayDriver::ObscureCursor
+	somewhere within this function to ensure that data is maintained accurately. A check
+	will be made by the system before the next MoveCursorTo call to show the cursor if
+	it is obscured.
+*/
+void
+DisplayDriverImpl::ObscureCursor()
+{
+	Lock();
+	fCursorHandler.Obscure();	
+	Unlock();
+
+}
+
+/*!
+	\brief Changes the cursor.
+	\param cursor The new cursor. Guaranteed to be non-NULL.
+	
+	The driver does not take ownership of the given cursor. Subclasses should make
+	a copy of the cursor passed to it. The default version of this function hides the
+	cursory, replaces it, and shows the cursor if previously visible.
+*/
+void
+DisplayDriverImpl::SetCursor(ServerCursor *cursor)
+{
+	Lock();
+	fCursorHandler.SetCursor(cursor);
+	Unlock();
+}
+
+//! Returns the cursor's current position
+BPoint
+DisplayDriverImpl::GetCursorPosition()
+{
+	Lock();
+	BPoint pos = fCursorHandler.GetPosition();
+	Unlock();
+	
+	return pos;
+}
+
+/*!
+	\brief Returns whether or not the cursor is currently obscured
+	\return True if obscured, false if not.
+*/
+bool
+DisplayDriverImpl::IsCursorObscured(bool state)
+{
+	Lock();
+	bool obscured = fCursorHandler.IsObscured();
+	Unlock();
+	
+	return obscured;
+}
+
 /*!
 	\brief Locks the driver
 	\param timeout Optional timeout specifier

src/servers/app/drawing/DisplayDriverPainter.cpp

@@ -128,7 +128,7 @@ DisplayDriverPainter::CopyRegionList(BList* list, BList* pList,
 	if (!clipReg || !Lock())
 		return;
 
-// This is the same implementation as in DisplayDriverImpl for now
+// This is the same implementation as in DisplayDriverPainter for now
 
 // since we're not using painter.... this won't do much good, will it?
 //	fPainter->ConstrainClipping(*clipReg);
@@ -755,6 +755,65 @@ DisplayDriverPainter::GetTruncatedStrings(const char **instrings,
 	printf("DisplayDriverPainter::GetTruncatedStrings()\n");
 }
 
+// HideCursor
+void
+DisplayDriverPainter::HideCursor()
+{
+	fGraphicsCard->SetCursorVisible(false);
+}
+
+// IsCursorHidden
+bool
+DisplayDriverPainter::IsCursorHidden()
+{
+	return !fGraphicsCard->IsCursorVisible();
+}
+
+// MoveCursorTo
+void
+DisplayDriverPainter::MoveCursorTo(const float &x, const float &y)
+{
+	fGraphicsCard->MoveCursorTo(x, y);
+}
+
+// ShowCursor
+void
+DisplayDriverPainter::ShowCursor()
+{
+	fGraphicsCard->SetCursorVisible(true);
+}
+
+// ObscureCursor
+void
+DisplayDriverPainter::ObscureCursor()
+{
+	// TODO: I don't think this has anything to do with the DisplayDriver
+	// implement elsewhere!!
+}
+
+// SetCursor
+void
+DisplayDriverPainter::SetCursor(ServerCursor *cursor)
+{
+	fGraphicsCard->SetCursor(cursor);
+}
+
+// GetCursorPosition
+BPoint
+DisplayDriverPainter::GetCursorPosition()
+{
+	return fGraphicsCard->GetCursorPosition();
+}
+
+// IsCursorObscured
+bool
+DisplayDriverPainter::IsCursorObscured(bool state)
+{
+	// TODO: I don't think this has anything to do with the DisplayDriver
+	// implement elsewhere!!
+	return false;
+}
+
 // Lock
 bool
 DisplayDriverPainter::Lock(bigtime_t timeout)

src/servers/app/drawing/DisplayDriverPainter.h

@@ -217,10 +217,8 @@ class DisplayDriverPainter : public DisplayDriver {
 													const float &maxwidth,
 													char **outstrings);
 	
-	virtual bool				Lock(bigtime_t timeout = B_INFINITE_TIMEOUT);
-	virtual void				Unlock();
-
-/*	virtual	void				HideCursor();
+	// cursor handling		
+	virtual	void				HideCursor();
 	virtual	bool				IsCursorHidden();
 	virtual	void				MoveCursorTo(	const float &x,
 												const float &y);
@@ -228,9 +226,12 @@ class DisplayDriverPainter : public DisplayDriver {
 	virtual	void				ObscureCursor();
 	virtual	void				SetCursor(ServerCursor *cursor);
 			BPoint				GetCursorPosition();
-	virtual	bool				IsCursorObscured(bool state);*/
+	virtual	bool				IsCursorObscured(bool state);
 	
 
+	virtual bool				Lock(bigtime_t timeout = B_INFINITE_TIMEOUT);
+	virtual void				Unlock();
+
 	// display mode access
 	virtual void				SetMode(const display_mode &mode);
 	

src/servers/app/drawing/HWInterface.cpp

@@ -1,14 +1,106 @@
 // HWInterface.cpp
 
+#include "ServerCursor.h"
+
 #include "HWInterface.h"
 
 // constructor
 HWInterface::HWInterface()
-	: BLocker("hw interface lock")
+	: BLocker("hw interface lock"),
+	  fCursor(NULL),
+	  fCursorVisible(true),
+	  fCursorLocation(0.5, 0.5)
 {
 }
 
 // destructor
 HWInterface::~HWInterface()
 {
+	delete fCursor;
 }
+
+// SetCursor
+void
+HWInterface::SetCursor(ServerCursor* cursor)
+{
+	if (Lock()) {
+		if (fCursor != cursor) {
+			BRect oldFrame = _CursorFrame();
+			delete fCursor;
+			fCursor = cursor;
+			Invalidate(oldFrame);
+			Invalidate(_CursorFrame());
+		}
+		Unlock();
+	}
+}
+
+// SetCursorVisible
+void
+HWInterface::SetCursorVisible(bool visible)
+{
+	if (Lock()) {
+		if (fCursorVisible != visible) {
+			fCursorVisible = visible;
+			Invalidate(_CursorFrame());
+		}
+		Unlock();
+	}
+}
+
+// IsCursorVisible
+bool
+HWInterface::IsCursorVisible()
+{
+	bool visible = true;
+	if (Lock()) {
+		visible = fCursorVisible;
+		Unlock();
+	}
+	return visible;
+}
+
+// MoveCursorTo
+void
+HWInterface::MoveCursorTo(const float& x, const float& y)
+{
+	if (Lock()) {
+		BPoint p(x, y);
+		if (p != fCursorLocation) {
+			BRect oldFrame = _CursorFrame();
+			fCursorLocation = p;
+			Invalidate(oldFrame);
+			Invalidate(_CursorFrame());
+		}
+		Unlock();
+	}
+}
+
+// GetCursorPosition
+BPoint
+HWInterface::GetCursorPosition()
+{
+	BPoint location;
+	if (Lock()) {
+		location = fCursorLocation;
+		Unlock();
+	}
+	return location;
+}
+
+// _CursorFrame
+//
+// PRE: the object must be locked
+BRect
+HWInterface::_CursorFrame() const
+{
+	BRect frame(0.0, 0.0, -1.0, -1.0);
+	if (fCursor && fCursorVisible) {
+		frame = fCursor->Bounds();
+		frame.OffsetTo(fCursorLocation - fCursor->GetHotSpot());
+	}
+	return frame;
+}
+
+
+

src/servers/app/drawing/HWInterface.h

@@ -13,9 +13,10 @@
 #include <GraphicsCard.h>
 #include <Locker.h>
 #include <OS.h>
+#include <Rect.h>
 
 class RenderingBuffer;
-class BRect;
+class ServerCursor;
 
 class HWInterface : public BLocker {
  public:
@@ -25,10 +26,10 @@ class HWInterface : public BLocker {
 	virtual	status_t			Initialize() = 0;
 	virtual	status_t			Shutdown() = 0;
 
+	// screen mode stuff
 	virtual	status_t			SetMode(const display_mode &mode) = 0;
 //	virtual	void				GetMode(display_mode *mode) = 0;
 
-
 	virtual status_t			GetDeviceInfo(accelerant_device_info *info) = 0;
 	virtual status_t			GetModeList(display_mode **mode_list,
 											uint32 *count) = 0;
@@ -46,6 +47,14 @@ class HWInterface : public BLocker {
 	virtual uint32				DPMSMode() const = 0;
 	virtual uint32				DPMSCapabilities() const = 0;
 
+	// cursor handling
+	virtual	void				SetCursor(ServerCursor* cursor);
+	virtual	void				SetCursorVisible(bool visible);
+	virtual	bool				IsCursorVisible();
+	virtual	void				MoveCursorTo(const float& x,
+											 const float& y);
+			BPoint				GetCursorPosition();
+
 	// frame buffer access
 	virtual	RenderingBuffer*	FrontBuffer() const = 0;
 	virtual	RenderingBuffer*	BackBuffer() const = 0;
@@ -54,6 +63,13 @@ class HWInterface : public BLocker {
 	virtual	status_t			Invalidate(const BRect& frame) = 0;
 	// while as CopyBackToFront() actually performs the operation
 	virtual	status_t			CopyBackToFront(const BRect& frame) = 0;
+
+ protected:
+			BRect				_CursorFrame() const;
+
+			ServerCursor*		fCursor;
+			bool				fCursorVisible;
+			BPoint				fCursorLocation;
 };
 
 #endif // HW_INTERFACE_H

src/servers/app/drawing/Painter/Painter.cpp

@@ -150,7 +150,7 @@ Painter::SetDrawData(const DrawData* data)
 	SetLowColor(data->lowcolor.GetColor32());
 	SetScale(data->scale);
 	SetPenSize(data->pensize);
-//	SetOrigin();
+//	fOrigin = data->coordOrigin;
 	SetDrawingMode(data->draw_mode);
 	SetBlendingMode(data->alphaSrcMode, data->alphaFncMode);
 	SetPenLocation(data->penlocation);

src/servers/app/drawing/ViewHWInterface.cpp

@@ -29,6 +29,7 @@
 #include "BitmapBuffer.h"
 #include "PortLink.h"
 #include "ServerConfig.h"
+#include "ServerCursor.h"
 #include "ServerProtocol.h"
 #include "UpdateQueue.h"
 
@@ -112,12 +113,6 @@ class CardView : public BView {
 private:
 			BPortLink*			fServerLink;
 			const BBitmap*		fBitmap;
-
-/*	int hide_cursor;
-	BBitmap *cursor;
-	
-	BRect cursorframe, oldcursorframe;
-	bool obscure_cursor;*/
 };
 
 class CardWindow : public BWindow {
@@ -157,31 +152,11 @@ CardView::CardView(BRect bounds)
 		return;
 	}
 	fServerLink = new BPortLink(serverInputPort);
-
-	// Create a cursor which isn't just a box
-/*	cursor=new BBitmap(BRect(0,0,20,20),B_RGBA32,true);
-	BView *v=new BView(cursor->Bounds(),"v", B_FOLLOW_NONE, B_WILL_DRAW);
-	hide_cursor=0;
-
-	cursor->Lock();
-	cursor->AddChild(v);
-
-	v->SetHighColor(255,255,255,0);
-	v->FillRect(cursor->Bounds());
-	v->SetHighColor(255,0,0,255);
-	v->FillTriangle(cursor->Bounds().LeftTop(),cursor->Bounds().RightTop(),cursor->Bounds().LeftBottom());
-
-	cursor->RemoveChild(v);
-	cursor->Unlock();
-	
-	cursorframe=cursor->Bounds();
-	oldcursorframe=cursor->Bounds();*/
 }
 
 CardView::~CardView()
 {
 	delete fServerLink;
-/*	delete cursor;*/
 }
 
 // AttachedToWindow
@@ -197,16 +172,6 @@ CardView::Draw(BRect updateRect)
 	if (fBitmap) {
 		DrawBitmapAsync(fBitmap, updateRect, updateRect);
 	}
-/*	if (viewbmp) {
-		DrawBitmapAsync(viewbmp,oldcursorframe,oldcursorframe);
-		DrawBitmapAsync(viewbmp,rect,rect);
-	
-		if (hide_cursor == 0 && obscure_cursor == false) {
-			SetDrawingMode(B_OP_ALPHA);
-			DrawBitmapAsync(cursor,cursor->Bounds(), cursorframe);
-			SetDrawingMode(B_OP_COPY);
-		}
-	}*/
 }
 
 // These functions emulate the Input Server by sending the *exact* same kind of messages
@@ -228,12 +193,11 @@ CardView::MouseMoved(BPoint pt, uint32 transit, const BMessage* dragMessage)
 {
 	if (!Bounds().Contains(pt))
 		return;
-// TODO: no cursor support yet
 
 	// A bug in R5 prevents this call from having an effect if
 	// called elsewhere, and calling it here works, if we're lucky :-)
-//	BCursor cursor(kEmptyCursor);
-//	SetViewCursor(&cursor, true);
+	BCursor cursor(kEmptyCursor);
+	SetViewCursor(&cursor, true);
 
 #ifdef ENABLE_INPUT_SERVER_EMULATION
 	send_mouse_moved(fServerLink, pt, Window()->CurrentMessage());
@@ -420,9 +384,6 @@ ViewHWInterface::SetMode(const display_mode &mode)
 
 printf("ViewHWInterface::SetMode(%s)\n", string_for_color_space((color_space)fDisplayMode.space));
 
-// left over code
-//	hide_cursor=0;
-
 	BRect frame(0.0, 0.0,
 				fDisplayMode.virtual_width - 1,
 				fDisplayMode.virtual_height - 1);
@@ -494,9 +455,6 @@ printf("ViewHWInterface::SetMode(%s)\n", string_for_color_space((color_space)fDi
 status_t
 ViewHWInterface::GetDeviceInfo(accelerant_device_info *info)
 {
-//	if(!info || !is_initialized)
-//		return B_ERROR;
-
 	// We really don't have to provide anything here because this is strictly
 	// a software-only driver, but we'll have some fun, anyway.
 	
@@ -514,11 +472,6 @@ ViewHWInterface::GetDeviceInfo(accelerant_device_info *info)
 status_t
 ViewHWInterface::GetModeList(display_mode **modes, uint32 *count)
 {
-//	if(!count || !is_initialized)
-//		return B_ERROR;
-
-//	screenwin->Lock();
-	
 	// DEPRECATED:
 	// NOTE: Originally, I was going to figure out good timing values to be 
 	// returned in each of the modes supported, but I won't bother, being this
@@ -576,7 +529,6 @@ ViewHWInterface::GetModeList(display_mode **modes, uint32 *count)
 		modes[i]->v_display_start=0;
 		modes[i]->flags=B_PARALLEL_ACCESS;
 	}
-//	screenwin->Unlock();
 	
 	return B_OK;
 }
@@ -675,16 +627,14 @@ ViewHWInterface::CopyBackToFront(const BRect& frame)
 //					   && area.Intersects(fBackBuffer->Bitmap()->Bounds())) {
 
 		const BBitmap* from = fBackBuffer->Bitmap();
-		const BBitmap* into = fFrontBuffer->Bitmap();
+//		const BBitmap* into = fFrontBuffer->Bitmap();
 
 		// make sure we don't copy out of bounds
 		area = from->Bounds() & area;
 //		area = into->Bounds() & area;
 
-		uint32 srcBPR = from->BytesPerRow();
-		uint32 dstBPR = into->BytesPerRow();
-		uint8* dst = (uint8*)into->Bits();
-		uint8* src = (uint8*)from->Bits();
+		uint32 srcBPR = fBackBuffer->BytesPerRow();
+		uint8* src = (uint8*)fBackBuffer->Bits();
 
 		// convert to integer coordinates
 		int32 x = (int32)floorf(area.left);
@@ -695,8 +645,100 @@ ViewHWInterface::CopyBackToFront(const BRect& frame)
 		// offset to left top pixel in source buffer (always B_RGBA32)
 		src += y * srcBPR + x * 4;
 
+		_CopyToFront(src, srcBPR, x, y, right, bottom);
+
+		_DrawCursor(area);
+
+		// update the region on screen
+		fWindow->Invalidate(area);
+	}
+
+	return B_OK;
+}
+
+// _DrawCursor
+void
+ViewHWInterface::_DrawCursor(BRect area) const
+{
+	BRect cf = _CursorFrame();
+	if (cf.IsValid() && area.Intersects(cf)) {
+		// clip to common area
+		area = area & cf;
+
+		int32 left = (int32)floorf(area.left);
+		int32 top = (int32)floorf(area.top);
+		int32 right = (int32)ceilf(area.right);
+		int32 bottom = (int32)ceilf(area.bottom);
+		int32 width = right - left + 1;
+		int32 height = bottom - top + 1;
+
+		// make a bitmap from the backbuffer
+		// that has the cursor blended on top of it
+
+		// blending buffer
+		uint8* buffer = new uint8[width * height * 4];
+
+		// offset into back buffer
+		uint8* src = (uint8*)fBackBuffer->Bits();
+		uint32 srcBPR = fBackBuffer->BytesPerRow();
+		src += top * srcBPR + left * 4;
+
+		// offset into cursor bitmap
+		uint8* crs = (uint8*)fCursor->Bits();
+		uint32 crsBPR = fCursor->BytesPerRow();
+		// since area is clipped to cf,
+		// the diff between top and cf.top is always positive,
+		// same for diff between left and cf.left
+		crs += (top - (int32)floorf(cf.top)) * crsBPR
+				+ (left - (int32)floorf(cf.left)) * 4;
+
+		uint8* dst = buffer;
+
+		// blending
+		for (int32 y = top; y <= bottom; y++) {
+			uint8* s = src;
+			uint8* c = crs;
+			uint8* d = dst;
+			for (int32 x = left; x <= right; x++) {
+				// assume backbuffer alpha = 255
+				// TODO: it appears alpha in cursor us upside down
+				uint8 a = 255 - c[3];
+				d[0] = (((s[0] - c[0]) * a) + (c[0] << 8)) >> 8;
+				d[1] = (((s[1] - c[1]) * a) + (c[1] << 8)) >> 8;
+				d[2] = (((s[2] - c[2]) * a) + (c[2] << 8)) >> 8;
+				d[3] = 255;
+				s += 4;
+				c += 4;
+				d += 4;
+			}
+			crs += crsBPR;
+			src += srcBPR;
+			dst += width * 4;
+		}
+
+		// copy result to front buffer
+		_CopyToFront(buffer, width * 4, left, top, right, bottom);
+
+		delete[] buffer;
+	}
+}
+
+// _CopyToFront
+//
+// * source is assumed to be already at the right offset
+// * source is assumed to be in B_RGBA32 format
+// * location in front buffer is calculated
+// * conversion from B_RGBA32 to format of front buffer is taken care of
+void
+ViewHWInterface::_CopyToFront(uint8* src, uint32 srcBPR,
+							  int32 x, int32 y,
+							  int32 right, int32 bottom) const
+{
+	uint8* dst = (uint8*)fFrontBuffer->Bits();
+	uint32 dstBPR = fFrontBuffer->BytesPerRow();
+
 	// transfer, handle colorspace conversion
-		switch (into->ColorSpace()) {
+	switch (fFrontBuffer->ColorSpace()) {
 		case B_RGB32:
 		case B_RGBA32: {
 			int32 bytes = (right - x + 1) * 4;
@@ -831,11 +873,6 @@ ViewHWInterface::CopyBackToFront(const BRect& frame)
 			break;
 	}
 	
-		// update the region on screen
-		fWindow->Invalidate(area);
-	}
-
-	return B_OK;
 }
 
 

src/servers/app/drawing/ViewHWInterface.h

@@ -57,6 +57,11 @@ class ViewHWInterface : public HWInterface {
 	virtual	status_t			CopyBackToFront(const BRect& area);
 
 private:
+			void				_DrawCursor(BRect area) const;
+			void				_CopyToFront(uint8* src, uint32 srcBPR,
+											 int32 x, int32 y,
+											 int32 right, int32 bottom) const;
+
 			BitmapBuffer*		fBackBuffer;
 			BitmapBuffer*		fFrontBuffer;