| Value | Meaning |
|---|---|
| sourceIn1 | Replace old with new where old was opaque. |
| sourceCopy | Replace old with new. |
| sourceOut | Replace old with new where old is transparent. |
| destinationIn | Clear old where new is transparent. |
| destinationAtop7 | Show old over new where new is opaque. |
| add10 | Sum old with new. |
| lighter10 | ditto |
| destinationOver | Show new under old. |
| destinationOut | Clear old where new is opaque. |
| sourceAtop | Show new over old where old is opaque. |
| sourceOver | Show new over old. |
| exclusiveOr | Show new and old, clear where both are opaque. |
Compositing operation for blending new drawing and old pixels. The sourceCopy, sourceIn, sourceOut, destinationAtop, and destinationIn operations may clear parts of the canvas outside the new drawing but within the clip region. Defaults to: sourceOver.