Benefits of wddm

1.

D3d runtime and DX graphics core subsystem have done more work, including management of memory and DMA.

 

2.

It is easier to create a surface.

Previously, 1). ddcancreatesurface 2). ddcreatesurface 3). d3dcreatesurfaceex; the first two are both core mode methods.

Now you only need createresource.

 

3.

Surface: Create, destroy; and lock and unlock pairs. (What does Shenma mean? Isn't this a feature in the past ?)

 

4.

Video memory, memory, and hosted surface are treated equally. Previously, it will be divided into different management points.

 

5.

Coloring erCodeThe translation is completed in the user mode. This eliminates the complexity of generating the coloring machine code in kernel mode. .

 

Http://msdn.microsoft.com/en-us/library/windows/hardware/ff538245 (V = vs.85). aspx
 

Bytes ---------------------------------------------------------------------------------------

 

1.

The displsy miniport driver must implement the new entry point function entry-points functions. It is used to interact with the operating system and the DX core subsystem.

Miniport driver is used to access all listed kernel functions.

 

2.

In the old WDM, the kernel-model display driver uses I/O control code (IOCTL) to communicate with the miniport driver, however, in wddm, miniport driver interacts with d3d runtime and DX kernel subsystem. Therefore, most IOCTL operations are unnecessary. Except video_query_color_capabilities and video_handle_videoparameters.

 

3.

The user-mode diplay driver must implement openadapter and createdevice.

 

4.

As mentioned previously, createresource replaces the original XX, XX, and XX.

 

5.

The method previously implemented in kernel-mode must be implemented in user-mode: omitted.

 

Http://msdn.microsoft.com/en-us/library/windows/hardware/ff568307 (V = vs.85). aspx