7月8日

1.DDI Functions

All display drivers must implement the DDI functions. However, only DrvEnableDriver must be exported from the display driver's DLL, which means that only

 DrvEnableDriver can use this exact name.

DrvEnableDriver

Returns pointers to DDI functions to GDI. The initial entry point that is exposed by the driver. The driver exposes the second entry point if DisplayInit is implemented.

http://msdn.microsoft.com/en-US/library/ee485901(v=winembedded.60).aspx#feedback

2.GDI Support Services

The GDI provides some services to support display drivers as predefined structures. The structures interact both with associated functions and with a few stand-alone C 

functions.

Predefined structures support brushes, palettes, translations, clipping regions, and stroke and fill paths.

Stand-alone C functions support device bitmaps and surfaces.

http://msdn.microsoft.com/en-US/library/ee481283(v=winembedded.60).aspx

3.Display Drivers and the Run-Time Image

The emulated blit functions are located in a library named Emul.lib. The display driver links to this library through a link directive during the driver's Sysgen build phase. 

The GPE library is provided in binary form and links to the driver during the Sysgen build phase.

The ROM Image Builder tool (Romimage.exe) creates run-time images. For most sample display drivers, the Common.bib file directs Romimage.exe to include the 

appropriate driver in the run-time image, based on the display environment variables selected. The Common.bib file is in 

the%_WINCEROOT%\Public\Common\OAK\Files directory.

http://msdn.microsoft.com/en-US/library/ee485628(v=winembedded.60).aspx

4.Line Drawing 

The process of drawing one or more lines is broken into three discrete phases: the prepare phase, the drawing phase, and the completion phase.

Step 1: Line drawing prepare phase

Line drawing begins when an application calls Polyline. GDI handles the call to Polyline. GDI validates that there are at least two vertices and that the line style is not 

NULL. GDI then calls the GPE DrvStrokePath function or, for a wide pen, DrvFillPath.
Step 2: Line drawing draw phase

After determining the appropriate line-drawing function, the DrvStrokePath function carries out the two nested loops. The following example shows the clipping rectangles 

a path falls into.

Step 3: Line drawing completion phase

A line drawing sequence ends with a call to the driver's GPE::Line function with the gpeComplete value as the phase parameter.

http://msdn.microsoft.com/en-US/library/ee481933(v=winembedded.60).aspx

5.Primary Display Drivers

The following sequence of steps shows the process of connecting and disconnecting from devices:

1.The CreateDC function provides the only way that GDI enables an application to create a connection to a graphic device. It also calls the driver's initialization functions.

 The device context returned from calls, such as BeginPaint and GetDC have been created by the Window Manager by calling CreateDC. 

2.After an application connects to a display driver and the calls to the driver's initialization function are complete, you can query, set attributes, and draw,

3.After you complete querying, setting attributes, and drawing, you can disconnect the application from the device. 

http://msdn.microsoft.com/en-US/library/ee482277(v=winembedded.60).aspx

6.How to Decide Whether to Use GPE in a Display Driver 

1. Familiarize yourself with the display driver architecture for Windows Embedded CE and with the GPE.

2. Familiarize yourself with the benefits and limitations of GPE display drivers.

3. Examine the display driver samples.

4. Familiarize yourself with GPE classes.

5. If you decide to use the GPE in the display driver, create a display driver based on GPE classes.

6. Implement functionality that takes advantage of the use of GPE base classes.

http://msdn.microsoft.com/en-US/library/ee485643(v=winembedded.60).aspx

7.palletized color 

意思是通过调用调色板得到的实际颜色,实际上就是查找颜色表。一般是为了减少表示颜色的数据量。

8.GUI

图形用户界面（Graphical User Interface，简称 GUI，又称图形用户接口）是指采用图形方式显示的计算机操作用户界面。