Introduction and Overview
The VideoHWVIDC module 0.48 provides hardware access for the native VIDC20 hardware used in RiscPC, A7000 and RiscStation hardware. The acceleration provided is described below. It covers the vast majority of common operations which are used by applications. The operations are broken down into the core components for the abstracted video system.
All features which are not supported by the hardware driver will be deferred to the software driver which will use direct screen access to provide the required operation, or update its internal state.
Glossary :
| Term | Meaning |
|---|---|
| 'Not supported' | The hardware driver does not provide any facilities for this feature; it will be passed to the software driver. |
| 'Supported' | The hardware driver provides this facility but it does not gain from specialised hardware features for faster operation. |
| 'Accelerated' | The hardware driver provides this facility and uses specialised hardware features to avoid direct screen access. |
Technical Details
Text (VDU4-style text output)
| Operation | Support |
|---|---|
| VideoV_Text_ChangeDestination | Not supported |
| VideoV_Text_DefineChar | Not supported |
| VideoV_Text_SetTextColour | Not supported |
| VideoV_Text_WriteTextChar | Not supported |
| VideoV_Text_TextCursor | Not supported |
| VideoV_Text_ClearBox | Not supported |
VDU graphics operations
| Operation | Support |
|---|---|
| VideoV_Graf_SetColour1 | Not supported |
| VideoV_Graf_SetColour2 | Not supported |
| VideoV_Graf_ChangeDestination | Not supported |
| VideoV_Graf_ChangeBase | Not supported |
| VideoV_Graf_ReadPrimitives | Not supported |
| VideoV_Graf_Rectangle | Not supported |
| VideoV_Graf_Triangle | Not supported |
| VideoV_Graf_Parallelogram | Not supported |
| VideoV_Graf_BlockCopy | Not supported |
| VideoV_Graf_CircleOutline | Not supported |
| VideoV_Graf_CircleFill | Not supported |
| VideoV_Graf_CircleArc | Not supported |
| VideoV_Graf_CircleSegment | Not supported |
| VideoV_Graf_CircleSector | Not supported |
| VideoV_Graf_EllipseOutline | Not supported |
| VideoV_Graf_EllipseFill | Not supported |
| VideoV_Graf_FillRight | Not supported |
| VideoV_Graf_FillLeftAndRight | Not supported |
| VideoV_Graf_FillFlood | Not supported |
| VideoV_Graf_PolyHLine | Not supported |
Graphics primitives
| Operation | Support |
|---|---|
| HLine | Not supported |
| VLine | Not supported |
| Point | Not supported |
Mouse pointer operations
| Operation | Support |
|---|---|
| VideoV_Pointer_Define | Supported |
| VideoV_Pointer_Select | Supported |
| VideoV_Pointer_Update | Supported |
| VideoV_Pointer_Remove | Supported |
| VideoV_Pointer_SetPalette | Supported |
Mode / screen operations
| Operation | Support |
|---|---|
| VideoV_Mode_VetMode | Supported |
| VideoV_Mode_SetMode | Supported |
| VideoV_Mode_Scroll | Accelerated through frame base scroll |
| VideoV_Mode_SetPalette | Supported |
| VideoV_Mode_Enable | Supported |
| VideoV_Mode_Disable | Supported |
| VideoV_Mode_PowerSave | Supported |
| VideoV_Mode_SetRGBTable | Supported |
| VideoV_Mode_AccelConfigure | Supported |
| VideoV_Mode_AccelControl | Supported |
| VideoV_Mode_DisplaySelect | Supported |
| VideoV_Mode_BankCount | Supported |
| VideoV_Mode_BankDisplay | Supported |
| VideoV_Mode_BankDriver | Supported |
| VideoV_Mode_BankCopy | Not supported |
| VSync IRQ provision | Supported |
| Monitor EDID acquisition | Not supported |