udi_gfx.h

Valid values

Ranges

Hardwired 1, or 0-1

The connector or engine is enabled (nonzero) or disabled (zero).  A disabled engine forwards all data from the previous stage unmodified.  A disabled connector does not send any data over the connector.  Drivers may power down the physical counterparts of disabled components to preserve power, and users should expect delays when enabling connectors or components representing framebuffers.  Disabling is however not recommended for sprite layers, which may repeatedly be enabled and disabled.  A disabled component can still have its state changed, and the driver must complete all commands and other state changes as expected, regardless of disabled or power state.  The valid ranges reported for this property may be 1 (always enabled) or 0-1 (either enabled or disabled).

Valid values

Any valid engine ID, provided no dependency cycles are created, or -1

Ranges

Any non-empty set of valid values.  Often hardwired.

Points to the engine that is processed before this unit.  In the case of a connector, it points to the last engine in a pipeline, and each engine points to the next engine in the sequence.  A value of -1 indicates a source that only yields black pixels.  Implementations must not allow cyclic structures.  Changing this value may reallocate resources, and engines that are no longer referenced may lose their data (but not their state) when it is not part of any pipeline.  If preservation is required, the ENABLE state should be used instead.  Valid ranges includes one or more from the list of engines and -1 combined.  In most cases, this property can not be modified.

Valid values

Any non-zero positive number.

Ranges

Contains at least one valid value.  Often only multiples of UNIT_WIDTH or a power of two are allowed.  May be hardwired.

Contains the amount of pixels in the horizontal direction.  For connectors, this is the amount of data pixels rendered horizontally.  For engines, this is the width in pixels of the image.  Pixels requested from an engine outside the range (0..width-1) are defined according to the UDI_GFX_PROP_CLIP property.  In some cases, hardware may support only fixed combinations of width and height.  In such cases, changing the width will also change the height to a corresponding valid number.  Valid ranges include any values strictly above zero.  For connectors, expect large continuous ranges, large ranges with a certain modulus, a limited number of fixed values, or a constant value.

Valid values

Any non-zero positive number.

Ranges

Contains at least one valid value.  Often only multiples of UNIT_HEIGHT or a power of two are allowed.  May be hardwired.

Contains the amount of pixels in the vertical direction.  Functions similar to the width property, but changing it will not alter the width property, and it’s range at any time contains the valid range for the currently selected width.

The first property index of the driver’s custom range.  These are not assigned directly assigned by the UDI specification, but may be specified in the operator tree.

Valid values

Ranges

Hardwired zero for connectors.  Any non-empty subset for engines, usually hardwired.

For engines, contains the behaviour for pixels requested outside the width and height of the engine.  Can be either 0 (pass from next stage), 1 (the coordinates are wrapped modulus the height and width), 2 (the coordinates overflow onto the next scanline horizontally, and wrap vertically), 3 (the coordinates overflow onto the next column vertically, and wrap horizontally).  Valid ranges contain one or more of these options.  For overlays and sprites, a value 0 is common.  For framebuffers, 2 is the most common value.  For connectors, this property is always 0 since they do not store pixel data

Valid values

Any non-zero positive value

Ranges

Any non-empty set of valid values.  May be hardwired to 1 for framebuffers, or a range of small values for hardware scaling, or any larger hardwired number or set for tiling engines.

Tiles are used to indicate that the hardware groups sets of pixels and have each group share certain properties, i.e. color or tile index, or share the same chroma subsample with only a different intensity.  If the engine has no such grouping, or shares all properties over the entire contents, the value of this property should be 1.  Some tile examples include rescaling, where a tile width of 2 indicates a pixel doubling in X direction, or in text mode where a tile width of 8 or 9 corresponds with the width of common bitmap fonts

Valid values

Any non-zero positive value

Ranges

Any non-empty set of valid values.  May be hardwired to 1 for framebuffers, or a range of small values for hardware scaling, or any larger hardwired number or set for tiling engines.

See UDI_GFX_PROP_UNIT_WIDTH, but for the Y direction.  Common values are 1-2 for framebuffers (doublescanning on or off), identical to the tile width, or mostly independent.

the ops number used for the graphics driver

the ops number used for the graphics application