diff options
| author | Shelley Chen <shchen@google.com> | 2020-07-10 14:52:43 -0700 |
|---|---|---|
| committer | Julius Werner <jwerner@chromium.org> | 2020-07-15 20:23:07 +0000 |
| commit | 31a37887392e81e8a24eca83f4b261019c05ebd5 (patch) | |
| tree | b9256963b5c73c8cd0e4719faaba55c7c7c97f83 /payloads/libpayload/include | |
| parent | df5571dc9d94717a3eb32c56c950715b504c1b52 (diff) | |
cbgfx: Add blend functions to calculate transparency
Up until now we have no way of adding transparency into our firmware
screens. Add set_blend() and clear_blend() functions to store alpha
value and rgb values to calculate alpha blending in
calculate_colors().
BUG=b:144969091,b:160839199
BRANCH=puff
TEST=dut-control power_state:rec
press ctrl-d
Ensure background is dimmed when dialog pops up
Change-Id: I95468f27836d34ab80392727d726a69c09dc168e
Signed-off-by: Shelley Chen <shchen@google.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/43358
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Yu-Ping Wu <yupingso@google.com>
Reviewed-by: Julius Werner <jwerner@chromium.org>
Diffstat (limited to 'payloads/libpayload/include')
| -rw-r--r-- | payloads/libpayload/include/cbgfx.h | 30 |
1 files changed, 30 insertions, 0 deletions
diff --git a/payloads/libpayload/include/cbgfx.h b/payloads/libpayload/include/cbgfx.h index 869f272722..84e76f26d1 100644 --- a/payloads/libpayload/include/cbgfx.h +++ b/payloads/libpayload/include/cbgfx.h @@ -210,3 +210,33 @@ int draw_bitmap_direct(const void *bitmap, size_t size, * in the original size are returned. */ int get_bitmap_dimension(const void *bitmap, size_t sz, struct scale *dim_rel); + +/** + * Setup alpha and rgb values for alpha blending. When alpha is != 0, + * this enables a translucent layer of color (defined by rgb) to be + * blended at a given translucency (alpha) to all things drawn. Call + * clear_blend() to disable alpha blending. + * + * @param[in] rgb Color for transparency + * @param[in] alpha Opacity of color, from 0-255 where + * 0 = completely transparent (no blending) + * 255 = max alpha argument + * + * @return CBGFX_* error codes + */ +int set_blend(const struct rgb_color *rgb, uint8_t alpha); + +/** + * Clear alpha and rgb values, thus disabling any alpha blending. + * + * @return CBGFX_* error codes + */ +void clear_blend(void); + +/** + * For calculating Alpha value from % opacity + * For reference: + * 255 = max alpha argument + * 0 = min alpha argument, 0% opacity + */ +#define ALPHA(percentage) MIN(255, (256 * percentage / 100)) |