Dear all,
We Porting the Graphic Engine with Qt in the Ezsdk5.03, but we have an transparent problem.
If we use the QT and Setting the Fb0 ARGB(8888), we can have alpha blending with osd layer and video layer.
http://processors.wiki.ti.com/index.php/DM814X_AM387X_VPSS_Video_Driver_User_Guide
But if we use the opengl function in Qt to draw the osd, we cannot blending it with video layer.
We also find the information in the link:
http://www.glprogramming.com/red/chapter04.html
Note: The alpha value (the A in RGBA) has no direct effect on the color displayed on the screen. It can be used for many things, including blending and transparency,
and it can have an effect on the values of R, G, and B that are written.
We guess the opengl es in Qt only support the RGB(888) format in the physical layer,the value A(8) may be always fix to 0xFF(not blending).
Is the opengl es with qt not support the alpha blending in hardware format(ARGB-->8888)?
Is it is possible to blend osd layer and video layer? And how to achieve it ? (We need pixel alpha blending in Opengl)
-------QT(fb0)---------- -----------Qt with OpenGL es (powervr)---------------
| |
blending (OK) blending(NG) ---->We need set it to be blending.
| |
--------Video----------- --------------------------------------------------------------------