diff --git a/src/ShaderManager.js b/src/ShaderManager.js
index 4fb3da5..3f0bc61 100644
--- a/src/ShaderManager.js
+++ b/src/ShaderManager.js
@@ -154,12 +154,12 @@ ShaderManager.EFFECTS = Object.keys(ShaderManager.EFFECT_INFO);
  */
 ShaderManager.DRAW_MODE = {
     /**
-     * Draw normally.
+     * Draw normally. Its output will use premultiplied alpha.
      */
     default: 'default',
 
     /**
-     * Un-premultiply alpha. Useful for reading pixels from GL into an ImageData object.
+     * Draw with non-premultiplied alpha. Useful for reading pixels from GL into an ImageData object.
      */
     straightAlpha: 'straightAlpha',