1 files changed, 12 insertions, 0 deletions
diff --git a/include/ws2812b.h b/include/ws2812b.h
index 2061379..6f8aff0 100644
--- a/include/ws2812b.h
+++ b/include/ws2812b.h
@@ -45,11 +45,23 @@ typedef struct {
       uint8_t r;
       uint8_t g;
       uint8_t b;
+
+      /* Color alpha. 0 is perfectly opaque, 255 is perfectly transparent). */
+      uint8_t a;
     };
     uint32_t color;
   };
 } rgb_t;
 
+typedef struct {
+  uint8_t mat[4][4];
+} rgb_mat_t;
+
+/** Returns the new RGB as if rgb1 was overlayed on top of rgb2. */
+rgb_t blend(rgb_t rgb1, rgb_t rgb2);
+
+rgb_t mat_mul(rgb_t rgb, const rgb_mat_t* mat);
+
 int write_rgb(struct ws2812b_buf* out, rgb_t color);
 
 void start_dma(struct ws2812b_buf* buf);