Transparency Support and/or Big-endian Framebuffer
"Mike Bourgeous" <[email protected]> Fri, 24 Feb 2006 02:26:31 -0800
| Newsgroups | gmane.linux.fbdev.user |
|---|---|
| Message-ID | <[email protected]> |
I'm working on a framebuffer driver for a high-definition tuner card's OSD, and I have two equally bad options for pixel format. I can choose 24-bit pixels, with every FOUR bytes in reverse order (even though pixels are three bytes long - that makes for some interesting pictures when it's not set up right), or 32-bit pixels, with mandatory transparency. When I try the 24-bit route, I get video, but it looks kind of like someone took the color columns of an LCD screen and mixed them up, so the red of one pixel will be before the green of the pixel to its left or something. When I do 32-bit, it seems that no programs pay attention to the transparency field of fb_var_screeninfo. fbi, for example, clears the screen to 0x00000000 before drawing its image data, leaving the screen black. If I manually set all of the alpha bytes to 0x7f (full opacity), the fbi image is displayed, but as soon as fbi updates the display everything's black again. Is it possible, without modifying userland software, to either 1. byte-swap every four bytes with three-byte wide pixels or 2. force the transparency byte of all 32-bit pixels to 0x7f ?? I have a modified version of libfbx (u4x.sf.net/projects/libfbx) that sets the transparency value correctly, which I used to test the framebuffer driver, but I'd really prefer to have this work without too much work in userspace. My main goal is to get X to display on the framebuffer. Any help or suggestions would be greatly appreciated. My framebuffer driver uses the following driver as a backend: http://myhd.sf.net/ Mike Bourgeous _________________________________________________________________ Express yourself instantly with MSN Messenger! Download today - it's FREE! http://messenger.msn.click-url.com/go/onm00200471ave/direct/01/ ------------------------------------------------------- This SF.Net email is sponsored by xPML, a groundbreaking scripting language that extends applications into web and mobile media. Attend the live webcast and join the prime developer group breaking into this new coding territory! http://sel.as-us.falkag.net/sel?cmd=lnk&kid=110944&bid=241720&dat=121642