At present the code that writes to a pixel is quite convoluted. It uses a colour map which is in the uclass and the same code is repeated in different places within video_bmp_display().
As a first step, create a function which can write a pixel from the bitmap, no matter what the display depth. Use any provided palette directly, rather than using the uclass version.
Signed-off-by: Simon Glass sjg@chromium.org ---
drivers/video/video_bmp.c | 75 +++++++++++++++++++++++++++------------ 1 file changed, 52 insertions(+), 23 deletions(-)
diff --git a/drivers/video/video_bmp.c b/drivers/video/video_bmp.c index 7b3e15b7094..8d152c894cb 100644 --- a/drivers/video/video_bmp.c +++ b/drivers/video/video_bmp.c @@ -13,12 +13,60 @@ #include <watchdog.h> #include <asm/unaligned.h>
-#ifdef CONFIG_VIDEO_BMP_RLE8 #define BMP_RLE8_ESCAPE 0 #define BMP_RLE8_EOL 0 #define BMP_RLE8_EOBMP 1 #define BMP_RLE8_DELTA 2
+/** + * get_bmp_col_16bpp() - Convert a colour-table entry into a 16bpp pixel value + * + * @return value to write to the 16bpp frame buffer for this palette entry + */ +static uint get_bmp_col_16bpp(struct bmp_color_table_entry cte) +{ + return ((cte.red << 8) & 0xf800) | + ((cte.green << 3) & 0x07e0) | + ((cte.blue >> 3) & 0x001f); +} + +/** + * write_pix8() - Write a pixel from a BMP image into the framebuffer + * + * This handles frame buffers with 8, 16, 24 or 32 bits per pixel + * + * @fb: Place in frame buffer to update + * @bpix: Frame buffer bits-per-pixel, which controls how many bytes are written + * @palette: BMP palette table + * @bmap: Pointer to BMP bitmap position to write. This contains a single byte + * which is either written directly (bpix == 8) or used to look up the + * palette to get a colour to write + */ +static void write_pix8(u8 *fb, uint bpix, struct bmp_color_table_entry *palette, + u8 *bmap) +{ + if (bpix == 8) { + *fb++ = *bmap; + } else if (bpix == 16) { + *(u16 *)fb = get_bmp_col_16bpp(palette[*bmap]); + } else { + /* Only support big endian */ + struct bmp_color_table_entry *cte = &palette[*bmap]; + + if (bpix == 24) { + *fb++ = cte->red; + *fb++ = cte->green; + *fb++ = cte->blue; + } else { + *fb++ = cte->blue; + *fb++ = cte->green; + *fb++ = cte->red; + *fb++ = 0; + } + } +} + +#ifdef CONFIG_VIDEO_BMP_RLE8 static void draw_unencoded_bitmap(ushort **fbp, uchar *bmap, ushort *cmap, int cnt) { @@ -258,7 +306,6 @@ int video_bmp_display(struct udevice *dev, ulong bmp_image, int x, int y, switch (bmp_bpix) { case 1: case 8: { - struct bmp_color_table_entry *cte; cmap_base = priv->cmap; #ifdef CONFIG_VIDEO_BMP_RLE8 u32 compression = get_unaligned_le32(&bmp->header.compression); @@ -281,27 +328,9 @@ int video_bmp_display(struct udevice *dev, ulong bmp_image, int x, int y, for (i = 0; i < height; ++i) { WATCHDOG_RESET(); for (j = 0; j < width; j++) { - if (bpix == 8) { - *fb++ = *bmap++; - } else if (bpix == 16) { - *(uint16_t *)fb = cmap_base[*bmap]; - bmap++; - fb += sizeof(uint16_t) / sizeof(*fb); - } else { - /* Only support big endian */ - cte = &palette[*bmap]; - bmap++; - if (bpix == 24) { - *(fb++) = cte->red; - *(fb++) = cte->green; - *(fb++) = cte->blue; - } else { - *(fb++) = cte->blue; - *(fb++) = cte->green; - *(fb++) = cte->red; - *(fb++) = 0; - } - } + write_pix8(fb, bpix, palette, bmap); + bmap++; + fb += bpix / 8; } bmap += (padded_width - width); fb -= byte_width + priv->line_length;