| Flag | Description |
| DDOVERLAYCAPS_FLIP | Supports surface flipping with overlays. |
| DDOVERLAYCAPS_FOURCC | Supports FOURCC pixel formats with overlays. Use IDirectDraw::GetFourCCCodes to determine which FOURCC formats are supported. |
| DDOVERLAYCAPS_ZORDER | Supports changing Z order of overlays. |
| DDOVERLAYCAPS_MIRRORLEFTRIGHT | Supports surface mirroring in the left-to-right direction for overlays. |
| DDOVERLAYCAPS_MIRRORUPDOWN | Supports surface mirroring in the up-to-down direction for overlays. |
| DDOVERLAYCAPS_CKEYSRC | Supports source color keying for overlays. |
| DDOVERLAYCAPS_CKEYSRCCLRSPACE | Supports source color-space keying for overlays. |
| DDOVERLAYCAPS_CKEYSRCCLRSPACEYUV | Supports source color-space keying for overlays with FOURCC pixel formats. |
| DDOVERLAYCAPS_CKEYDEST | Supports destination color keying for overlays. |
| DDOVERLAYCAPS_CKEYDESTCLRSPACE | Supports destination colo-space keying for overlays. |
| DDOVERLAYCAPS_CKEYDESTCLRSPACEYUV | Supports destination color-space keying for overlays with FOURCC pixel formats. |
| DDOVERLAYCAPS_CKEYBOTH | Supports simultaneous source and destination color keying for overlays. |
| DDOVERLAYCAPS_ALPHADEST | Supports destination alpha blending for overlays. |
| DDOVERLAYCAPS_ALPHASRC | Supports source alpha blending for overlays. |
| DDOVERLAYCAPS_ALPHADESTNEG | Supports inverted destination alpha blending for overlays. |
| DDOVERLAYCAPS_ALPHASRCNEG | Supports inverted source alpha blending for overlays. |
| DDOVERLAYCAPS_ALPHACONSTANT | Supports constant alpha blending for overlays (specified in the DDOVERLAYFX structure). |
| DDOVERLAYCAPS_ALPHAPREMULT | Supports premultiplied alpha pixel formats for overlay alpha blending. |
| DDOVERLAYCAPS_ALPHANONPREMULT | Supports non-premultiplied alpha pixel formats for overlay alpha blending. |
| DDOVERLAYCAPS_ALPHAANDKEYDEST | Supports simultaneous source alpha blending with a destination color key for overlays. |
| DDOVERLAYCAPS_OVERLAYSUPPORT | Supports overlay surfaces. |