subdivided rendering on swapchainbackgroundpanel

Question

Hi,

I'm currently developing a Direct2D+Xaml app using swapchainbackgroundpanel. The drawing-operations take too long to perform them at a time. So I want to render content, present the backbuffer and then render further content on top of that content, then present it again and so on. So you could describe it as a subdivided rendering with interim presentation. Which is the best solution to do so? Maybe rendering to a bitmap and copy the content to the backbuffer each time?

Any suggestions would be helpful! Thanks.

Answer 1

Maybe I've found a solution! Each Windows-Store-app has to use DXGI_SWAP_EFFECT_FLIP_SEQUENTIAL as the swap-effect. So i could specify a scroll-rect with the size of the swapchainbuffers and without offset, so the buffer gets copied among presentation and rendering. Is there any tutorial how to do that, because http://msdn.microsoft.com/en-us/library/windows/desktop/hh706345(v=vs.85).aspx doesn't show c++-syntax. This gives an error:

	DXGI_PRESENT_PARAMETERS parameters = {0};
	parameters.DirtyRectsCount = 0;
	parameters.pDirtyRects = nullptr;
	RECT scrollRect;
	scrollRect.left = 0.0f;
	scrollRect.top = 0.0f;
	scrollRect.right = m_windowBounds.Width;
	scrollRect.bottom = m_windowBounds.Height;
	parameters.pScrollRect = &scrollRect;
	POINT rectOffset;
	rectOffset.x = 0.0f;
	rectOffset.y = 0.0f;
	parameters.pScrollOffset = &rectOffset;
	
	HRESULT hr = m_swapChain->Present1(1, 0, &parameters);