h6. [[OS SWI Calls]] h6(. » [[OS_SpriteOp]] h6((. » OS_SpriteOp 43 - Read pixel mask h2. OS_SpriteOp 43 - Read pixel mask h5. (SWI &2E) |_<^{width:4em}. Entry | | |<^. R0 |<^. 43 (Reason code) + [[OS_SpriteOp|Area value]]| |<^. R1 |<^. Unused/[[Format Of Sprite Area|Sprite area]] (as defined by area value in R0) | |<^. R2 |<^. Sprite name/[[Format Of Sprite|pointer]] (as defined by area value in R0) | |<^. R3 |<^. X coordinate | |<^. R4 |<^. Y coordinate | |_<^{width:4em}. Exit | | |<^. R5 |<^. Mask value | |\2<^. All other registers preserved| h4. Use This call allows the value of a sprite mask pixel to be read. h4. Notes Coordinates are specified in pixels, with (0,0) being the bottom-left corner of the sprite. For sprites with the wide mask flag set in the [[Sprite Mode Word]], the returned value is an alpha value between 0 and 255, with 255 representing a fully opaque pixel and 0 representing a fully transparent pixel. For other sprites, the returned value is either 0 or 1, representing transparent and opaque respectively. If the sprite lacks a mask, the value returned is the appropriate value for if the pixel was opaque (i.e. 255 or 1). h4. See also * [[Format Of Sprite]] * [[Format Of Sprite Area]] * [[Sprite Mode Word]] * [[OS_SpriteOp]] * [[OS_SpriteOp 44|OS_SpriteOp 44 - Write pixel mask]]