libpayload: cbgfx: Add color mapping functionality

Similar to set_blend(), add set_color_map() for mapping background and
foreground colors of a bitmap. Also add clear_color_map() for clearing
the saved color mappings.

Note that when drawing a bitmap, the color mapping will be applied
before blending.

Also remove unnecessary initialization for static variable 'blend'.

BRANCH=puff
BUG=b:146399181, b:162357639
TEST=emerge-puff libpayload

Change-Id: I640ff3e8455cd4aaa5a41d03a0183dff282648a5
Signed-off-by: Yu-Ping Wu <yupingso@chromium.org>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/44375
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Joel Kitching <kitching@google.com>
Reviewed-by: Julius Werner <jwerner@chromium.org>

1 files changed, 18 insertions, 2 deletions

diff --git a/payloads/libpayload/include/cbgfx.h b/payloads/libpayload/include/cbgfx.h
index f2883b0c43..85b61a7b10 100644
--- a/payloads/libpayload/include/cbgfx.h
+++ b/payloads/libpayload/include/cbgfx.h
@@ -228,6 +228,24 @@ int draw_bitmap_direct(const void *bitmap, size_t size,
 int get_bitmap_dimension(const void *bitmap, size_t sz, struct scale *dim_rel);
 
 /**
+ * Setup color mappings of background and foreground colors. Black and white
+ * pixels will be mapped to the background and foreground colors, respectively.
+ * Call clear_color_map() to disabled color mapping.
+ *
+ * @param[in] background	Background color.
+ * @param[in] foreground	Foreground color.
+ *
+ * @return CBGFX_* error codes
+ */
+int set_color_map(const struct rgb_color *background,
+		  const struct rgb_color *foreground);
+
+/**
+ * Clear color mappings.
+ */
+void clear_color_map(void);
+
+/**
  * 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
@@ -244,8 +262,6 @@ 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);