Rockbox

Hello,

attached is a patch to greatly speed up SDL screen updates
used by the simulator and RaaA (f.e. on the Nokia N900 ;)).

The current code calls SDL_FillRectangle() for every pixel, which is very slow.

We can speed things up greatly by using SDL_BlitSurface()
if the LCD_DEPTH is >= 8 and the pixel format is normal RGB.

Also don't call SDL_LockSurface() in the pixel-by-pixel code
as it's only needed if we are manipulating pixels directly.

Things to note:
- Right now it only works for LCD_DEPTH >= 8 and LCD_PIXELFORMAT == RGB565
- LCD_SoftStretch used for zooming is marked as unstable in the SDL API.

Best regards,
Thomas

 b/firmware/target/hosted/sdl/lcd-sdl.c    |   37 +++++++++++++++++++++++++-----
 b/firmware/target/hosted/sdl/system-sdl.c |   10 +++++---
 2 files changed, 38 insertions(+), 9 deletions(-)