diff -r 89d6a7a84779 -r 25a17d01db0c Symbian3/PDK/Source/GUID-599C9890-3AC8-46D3-A8C3-34CAAB5A61CF.dita --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/Symbian3/PDK/Source/GUID-599C9890-3AC8-46D3-A8C3-34CAAB5A61CF.dita Fri Jan 22 18:26:19 2010 +0000 @@ -0,0 +1,91 @@ + + + + + +Implementing +eglCreateWindowSurfaceThis topic explains how to implement eglCreateWindowSurface() on +the Symbian platform. +

The steps are as follows:

+
    +

  1. Use RSurfaceManager and +typically RChunk to create a composition surface. The details +vary depending on the type of memory that is to be used for the composition +surface's buffers. For example, the details are different when specialized +graphics memory is used rather than standard CPU memory.

    2. +

  2. Assign the composition +surface to an RWindow by calling:

    TInt +SetBackgroundSurface(const TSurfaceConfiguration& aConfiguration, TBool +aTriggerRedraw);

    Ensure that both the extent +and viewport of the TSurfaceConfiguration are set to the +full extent of the surface.

    3. +
+

The following table provides a summary of the key APIs.

+ + + + + +API +Description + + + + +

RSurfaceManager

+

The client-side API of the Surface +Manager. This provides methods to create, open and close composition +surfaces and to map a composition surface to an actual memory address.

Use +this API to create the composition surface.

+ + +

RSurfaceUpdateSession

+

The client-side API of the Surface +Update Server. This provides a channel for a surface's stakeholders +to inform each other of changes.

Use this as follows:

    +

  • To post a buffer for +composition.

    • +

  • To wait for the composition +of a buffer to complete.

    • +
 + + +

RWindowBase::SetBackgroundSurface()

+

Part of the Window Server client-side API, this function sets the +background of a window to be a given composition surface (called an external +surface in the Window +Server documentation). This means that when an RWindow is +moved, Window Server automatically moves its associated background surface.

This +function does the following:

    +

  • Positions the composition +surface in a layer below the UI layer, positioned directly below the RWindow.

    • +

  • Sets the background +color of the RWindow to transparent. This allows the composition +surface to show through. Any existing CWindowGc drawing +to the RWindow is retained in the foreground.

    • +

There are two forms of this function:

    +

  • One simply takes the +surface ID as an argument. This auto-stretches the background surface to fit +the window and causes temporary distortion of the EGL window surface between +a resize occurring and the next call to eglSwapBuffers().

    • +

  • The other has two arguments—a TSurfaceConfiguration and +a TBool. You can set the extent and viewport in the TSurfaceConfiguration to +match the full extent of the surface. This avoids the auto-stretching of the +surface.

    • +

See External +Surfaces Overview for an introduction to some of the key concepts.

+ + + +
 +Window Surface +Implementation Overview +Implementing +eglSwapBuffers + \ No newline at end of file