From 72061047d1cbe2f9c8728d1cde302343bb8dd784 Mon Sep 17 00:00:00 2001 From: Jens Arnold Date: Sat, 30 May 2009 23:35:44 +0000 Subject: Two tiny optimisations for mono bitmap drawing on greyscale displays: (1) H1x0, M5: Manipulate destination masks directly for the aligned case - ~0.7% speedup. (2) Greyscale ipods: Use sentinel method for reloading data like the 16 bit driver does - ~1.5% speedup. git-svn-id: svn://svn.rockbox.org/rockbox/trunk@21139 a1c6a512-1295-4272-9138-f99709370657 --- firmware/drivers/lcd-2bit-horz.c | 10 ++++------ 1 file changed, 4 insertions(+), 6 deletions(-) (limited to 'firmware/drivers/lcd-2bit-horz.c') diff --git a/firmware/drivers/lcd-2bit-horz.c b/firmware/drivers/lcd-2bit-horz.c index a9a691cabd..4dc82deae0 100644 --- a/firmware/drivers/lcd-2bit-horz.c +++ b/firmware/drivers/lcd-2bit-horz.c @@ -732,9 +732,8 @@ void ICODE_ATTR lcd_mono_bitmap_part(const unsigned char *src, int src_x, do { const unsigned char *src_col = src++; - unsigned data = *src_col >> src_y; - int numbits = 8 - ((int)src_y); - + unsigned data = (*src_col | 0x100) >> src_y; /* bit 8 == sentinel */ + ymax = y + height; ny = y; do @@ -747,11 +746,10 @@ void ICODE_ATTR lcd_mono_bitmap_part(const unsigned char *src, int src_x, ny++; data >>= 1; - if (--numbits == 0) + if (data == 0x001) { src_col += stride; - data = *src_col; - numbits = 8; + data = *src_col | 0x100; } } while (ny < ymax); -- cgit v1.2.3