* Refined overlay support a bit: we now allow as many overlay bitmaps to be

created as the graphics driver does.
* Also, B_BITMAP_RESERVE_OVERLAY_CHANNEL should now work as expected.
* We're no longer using the B_OVERLAY_COUNT hook anymore - that one really
  looks like a misconception to me; I don't see how it can be useful.


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@17196 a95241bf-73f2-0310-859d-f6bbb57e9c96

src/servers/app/BitmapManager.cpp

@@ -86,24 +86,24 @@ BitmapManager::CreateBitmap(ClientMemoryAllocator* allocator, HWInterface& hwInt
 	if (!locker.IsLocked())
 		return NULL;
 
-// TODO: create an overlay bitmap if graphics card supports it
-	if (flags & B_BITMAP_WILL_OVERLAY) {
-		if (!hwInterface.WriteLock()
-			|| !hwInterface.CheckOverlayRestrictions(bounds.IntegerWidth() + 1,
-					bounds.IntegerHeight() + 1, space)) {
-			hwInterface.WriteUnlock();
-			return NULL;
-		}
+	overlay_token overlayToken = NULL;
 
-		// We now hold the HWInterface write lock!
-		// Keeping the interface locked makes sure the overlay is still
-		// available when we allocate the buffer
+	if (flags & B_BITMAP_WILL_OVERLAY) {
+		if (!hwInterface.CheckOverlayRestrictions(bounds.IntegerWidth() + 1,
+				bounds.IntegerHeight() + 1, space))
+			return NULL;
+
+		if (flags & B_BITMAP_RESERVE_OVERLAY_CHANNEL) {
+			overlayToken = hwInterface.AcquireOverlayChannel();
+			if (overlayToken == NULL)
+				return NULL;
+		}
 	}
 
 	ServerBitmap* bitmap = new(nothrow) ServerBitmap(bounds, space, flags, bytesPerRow);
 	if (bitmap == NULL) {
-		if (flags & B_BITMAP_WILL_OVERLAY)
-			hwInterface.WriteUnlock();
+		if (overlayToken != NULL)
+			hwInterface.ReleaseOverlayChannel(overlayToken);
 
 		return NULL;
 	}
@@ -120,18 +120,20 @@ BitmapManager::CreateBitmap(ClientMemoryAllocator* allocator, HWInterface& hwInt
 				bitmap->Height(), space);
 		}
 
-		hwInterface.WriteUnlock();
-
 		if (overlayBuffer != NULL) {
 			overlayCookie->SetOverlayBuffer(overlayBuffer);
+			overlayCookie->SetOverlayToken(overlayToken);
+
 			bitmap->fAllocationCookie = overlayCookie;
 			bitmap->fBytesPerRow = overlayBuffer->bytes_per_row;
 
 			buffer = (uint8*)overlayBuffer->buffer;
 			if (_allocationType)
 				*_allocationType = kFramebuffer;
-		} else
+		} else {
+			hwInterface.ReleaseOverlayChannel(overlayToken);			
 			delete overlayCookie;
+		}
 	} else if (allocator != NULL) {
 		bool newArea;
 		cookie = allocator->Allocate(bitmap->BitsLength(), (void**)&buffer, newArea);

src/servers/app/ServerBitmap.cpp

@@ -363,13 +363,15 @@ UtilityBitmap::~UtilityBitmap()
 OverlayCookie::OverlayCookie(HWInterface& interface)
 	:
 	fHWInterface(interface),
-	fOverlayBuffer(NULL)
+	fOverlayBuffer(NULL),
+	fOverlayToken(NULL)
 {
 }
 
 
 OverlayCookie::~OverlayCookie()
 {
+	fHWInterface.ReleaseOverlayChannel(fOverlayToken);
 	fHWInterface.FreeOverlayBuffer(fOverlayBuffer);
 }
 
@@ -382,8 +384,22 @@ OverlayCookie::SetOverlayBuffer(const overlay_buffer* overlayBuffer)
 
 
 const overlay_buffer*
-OverlayCookie::OverlayBuffer()
+OverlayCookie::OverlayBuffer() const
 {
 	return fOverlayBuffer;
 }
 
+
+void
+OverlayCookie::SetOverlayToken(overlay_token token)
+{
+	fOverlayToken = token;
+}
+
+
+overlay_token
+OverlayCookie::OverlayToken() const
+{
+	return fOverlayToken;
+}
+

src/servers/app/ServerBitmap.h

@@ -141,11 +141,15 @@ class OverlayCookie {
 		~OverlayCookie();
 
 		void SetOverlayBuffer(const overlay_buffer* overlayBuffer);
-		const overlay_buffer* OverlayBuffer();
+		const overlay_buffer* OverlayBuffer() const;
+
+		void SetOverlayToken(overlay_token token);
+		overlay_token OverlayToken() const;
 
 	private:
-		HWInterface& fHWInterface;
-		const overlay_buffer* fOverlayBuffer;
+		HWInterface&			fHWInterface;
+		const overlay_buffer*	fOverlayBuffer;
+		overlay_token			fOverlayToken;
 };
 
 // ShallowCopy

src/servers/app/drawing/AccelerantHWInterface.cpp

@@ -101,8 +101,6 @@ AccelerantHWInterface::AccelerantHWInterface()
 		fBackBuffer(NULL),
 		fFrontBuffer(new (nothrow) AccelerantBuffer()),
 
-		fUsedOverlays(0),
-
 		fRectParams(new (nothrow) fill_rect_params[kDefaultParamsCount]),
 		fRectParamsCount(kDefaultParamsCount),
 		fBlitParams(new (nothrow) blit_params[kDefaultParamsCount]),
@@ -334,8 +332,8 @@ AccelerantHWInterface::_SetupDefaultHooks()
 	fAccReleaseOverlayBuffer = (release_overlay_buffer)fAccelerantHook(B_RELEASE_OVERLAY_BUFFER, NULL);
 	fAccGetOverlayConstraints = (get_overlay_constraints)fAccelerantHook(B_GET_OVERLAY_CONSTRAINTS, NULL);
 	fAccAllocateOverlay = (allocate_overlay)fAccelerantHook(B_ALLOCATE_OVERLAY, NULL);
-	fReleaseOverlay = (release_overlay)fAccelerantHook(B_RELEASE_OVERLAY, NULL);
-	fConfigureOverlay = (configure_overlay)fAccelerantHook(B_CONFIGURE_OVERLAY, NULL);
+	fAccReleaseOverlay = (release_overlay)fAccelerantHook(B_RELEASE_OVERLAY, NULL);
+	fAccConfigureOverlay = (configure_overlay)fAccelerantHook(B_CONFIGURE_OVERLAY, NULL);
 
 	return B_OK;
 }
@@ -687,26 +685,45 @@ AccelerantHWInterface::AvailableHWAcceleration() const
 }
 
 
+overlay_token
+AccelerantHWInterface::AcquireOverlayChannel()
+{
+	if (fAccAllocateOverlay == NULL
+		|| fAccReleaseOverlay == NULL)
+		return NULL;
+
+	// The current display mode only matters at the time we're planning on
+	// showing the overlay channel on screen - that's why we can't use
+	// the B_OVERLAY_COUNT hook.
+	// TODO: remove fAccOverlayCount if we're not going to need it at all.
+
+	return fAccAllocateOverlay();
+}
+
+
+void
+AccelerantHWInterface::ReleaseOverlayChannel(overlay_token token)
+{
+	if (token == NULL)
+		return;
+
+	fAccReleaseOverlay(token);
+}
+
+
 bool
 AccelerantHWInterface::CheckOverlayRestrictions(int32 width, int32 height,
 	color_space colorSpace)
 {
 	// check if the current display mode supports overlay
 	
-	if (fAccOverlayCount == NULL
-		|| fAccOverlaySupportedSpaces == NULL
+	if (fAccOverlaySupportedSpaces == NULL
 		|| fAccGetOverlayConstraints == NULL
 		|| fAccAllocateOverlayBuffer == NULL
 		|| fAccReleaseOverlayBuffer == NULL
 		|| (fDisplayMode.flags & B_SUPPORTS_OVERLAYS) == 0)
 		return false;
 
-	// check if there is an overlay buffer available
-
-	uint32 available = fAccOverlayCount(&fDisplayMode);
-	if ((int32)available <= fUsedOverlays)
-		return false;
-
 	// Note: we can't really check the size of the overlay upfront - we
 	// must assume fAccAllocateOverlayBuffer() will fail in that case.
 	if (width < 0 || width > 65535 || height < 0 || height > 65535)
@@ -733,11 +750,7 @@ AccelerantHWInterface::AllocateOverlayBuffer(int32 width, int32 height, color_sp
 	if (fAccAllocateOverlayBuffer == NULL)
 		return NULL;
 
-	const overlay_buffer* buffer = fAccAllocateOverlayBuffer(space, width, height);
-	if (buffer != NULL)
-		atomic_add(&fUsedOverlays, 1);
-
-	return buffer;
+	return fAccAllocateOverlayBuffer(space, width, height);
 }
 
 
@@ -747,7 +760,6 @@ AccelerantHWInterface::FreeOverlayBuffer(const overlay_buffer* buffer)
 	if (buffer == NULL || fAccReleaseOverlayBuffer == NULL)
 		return;
 
-	atomic_add(&fUsedOverlays, -1);
 	fAccReleaseOverlayBuffer(buffer);
 }
 

src/servers/app/drawing/AccelerantHWInterface.h

@@ -56,6 +56,9 @@ public:
 	virtual	uint32				AvailableHWAcceleration() const;
 
 	// overlay support
+	virtual overlay_token		AcquireOverlayChannel();
+	virtual void				ReleaseOverlayChannel(overlay_token token);
+
 	virtual bool				CheckOverlayRestrictions(int32 width, int32 height,
 									color_space colorSpace);
 	virtual const overlay_buffer* AllocateOverlayBuffer(int32 width, int32 height,
@@ -137,8 +140,8 @@ private:
 		release_overlay_buffer		fAccReleaseOverlayBuffer;
 		get_overlay_constraints		fAccGetOverlayConstraints;
 		allocate_overlay			fAccAllocateOverlay;
-		release_overlay				fReleaseOverlay;
-		configure_overlay			fConfigureOverlay;
+		release_overlay				fAccReleaseOverlay;
+		configure_overlay			fAccConfigureOverlay;
 
 		frame_buffer_config		fFrameBufferConfig;
 		int						fModeCount;
@@ -149,8 +152,6 @@ private:
 
 		display_mode			fDisplayMode;
 
-		vint32					fUsedOverlays;
-
 mutable	fill_rect_params*		fRectParams;
 mutable	uint32					fRectParamsCount;
 mutable	blit_params*			fBlitParams;

src/servers/app/drawing/HWInterface.cpp

@@ -302,6 +302,19 @@ HWInterface::CopyBackToFront(const BRect& frame)
 }
 
 
+overlay_token
+HWInterface::AcquireOverlayChannel()
+{
+	return NULL;
+}
+
+
+void
+HWInterface::ReleaseOverlayChannel(overlay_token token)
+{
+}
+
+
 bool
 HWInterface::CheckOverlayRestrictions(int32 width, int32 height, color_space colorSpace)
 {

src/servers/app/drawing/HWInterface.h

@@ -97,6 +97,9 @@ class HWInterface : public MultiLocker {
 											  const BPoint& offsetFromCursor);
 
 	// overlay support
+	virtual overlay_token		AcquireOverlayChannel();
+	virtual void				ReleaseOverlayChannel(overlay_token token);
+
 	virtual bool				CheckOverlayRestrictions(int32 width, int32 height,
 									color_space colorSpace);
 	virtual const overlay_buffer* AllocateOverlayBuffer(int32 width, int32 height,