Interfaces for video and 2D/3D graphics.
Mostly TBD at this point.
Basic frame buffer interface.
Intended for direct access to hardware-supported 2D drawing surfaces. Exposes the associated memory (VRAM) and the palette, if present.
Values for the Property argument in the GetProperty method.
Total length, in bytes, of the frame buffer.
Total length, in bytes, of one horizontal line (video scanline). Includes both the visible and the non visible portions.
Length in bytes of the visible portion of one horizontal line.
Length in bytes of the initial (left side) invisible portion of one horizontal line. Usually zero.
Total number of scanlines. Includes both the visible and the non visible ones.
Number of visible scanlines.
Number of invisible scanlines at the start of the frame buffer. Usually zero.
Number of effective bits in a pixel.
Number of bytes in a pixel. Accounts for spacing between adjecent pixels
The meaning of one pixel value, a constant of type PIXEL_ENCODING . A pixel value might be a simple index into a palette, or the encoding of coordinates in a color space such as RGB or YUV.
Summarization of the visual properties of the frame buffer, a constant of type FRAMEBUFFER_MODE
Number of addressable entries in the palette. Usually a power of 2.
Number of effective bits in a palette entry.
Number of bytes in a palette entry. Accounts for any unused bits.
The meaning of one palette entry, a constant of type PIXEL_ENCODING. A palette entry is the encoding of coordinates in a color space such as RGB or YUV.
Values for Mode arguments in IFrameBuffer methods and returned values.
Doom's favorite video mode.
Another popular video mode.
Mode has not been set yet.
Meaning of a pixel value in the frame buffer memory or in the palette.
A pixel value is an index into the associated palette. The value 0 will index the first entry in the palette, this in turn can be retrieved with GetPaletteEntry method. The encoding of a palette entry can be retrieved with the GetProperty method.
A pixel value is an ordered triple of 8 bit values, one each for the red, green and blue components.
A pixel value is an ordered triple of 8 bit values, one each for the red, green and blue components, followed by a padding byte.
Makes the frame buffer accessible to the caller.
Address where the frame buffer should be mapped, passed by reference. If the pointed-to value is NULL the caller indicates no mapping preference and the implementation of this method will select an appropriate address. Note that this might be mandatory in the absence of virtual memory. Upon return, the field will contain the (virtual) address of the start of the frame buffer. An argument value of NULL is not acceptable.
Length of the frame buffer to be mapped. If the pointed-to integer is 0 the whole frame buffer is mapped, otherwise only the requested initial portion of it. This value might be rounded up to a multiple of a pagesize in the presence of virtual memory. Upon return, this field will contain the mapped length in bytes of the frame buffer. An argument value of NULL is not acceptable.
The combination of in/out values was unacceptable.
Makes the frame buffer unaccessible to the caller.
The call might fail in the absence of hardware memory protection.
Address where the frame buffer had previously been mapped. An argument value of NULL might be acceptable, depending on the implementation, and will remove all the mappings of the frame buffer.
The frame buffer was never mapped as indicated.
Returns one of the properties of the frame buffer.
The desired property.
Where to return the current value of the desired property.
Invalid property or pointer argument.
Atomically change a number of properties of the frame buffer.
The desired video mode.
Something is wrong with the arguments.
This frame buffer does not implement the given mode.
Returns the entire content of the palette associated with the frame buffer.
This might be faster than asking for individual entries, for instance if the hardware uses auto-increment.
The buffer where to return the palette contents.
Length of the passed buffer.
Format in which the palette should be returned. The call might fail if this is not the same format returned as the PALETTE_ENCODING property of the frame buffer.
The buffer or its length are unacceptable.
Returns an individual entry in the palette associated with the frame buffer.
There have been cases of palettes that are only readable in full, in one such case this call might fail.
The index of the desired entry, starting at 0.
The buffer where to return the palette entry.
Length of the passed buffer.
Format in which the palette should be returned. The call might fail if this is not the same format returned as the PALETTE_ENCODING property of the frame buffer.
The index is invalid or the buffer is unacceptable.
Changes the entire content of the palette associated with the frame buffer.
This might be faster than changing individual entries, for instance if the hardware uses auto-increment.
The buffer with the palette contents.
Length of the passed buffer.
Format of entries in the palette. The call might fail if this is not the same format returned as the PALETTE_ENCODING property of the frame buffer.
The buffer or its length are unacceptable.
Changes an individual entry in the palette associated with the frame buffer.
There have been cases of palettes that are only writeable in full, in one such case this call might fail.
The index of the desired entry, starting at 0.
The buffer with the palette entry contents.
Length of the passed buffer.
Format of entries in the palette. The call might fail if this is not the same format returned as the PALETTE_ENCODING property of the frame buffer.
The index is invalid or the buffer is unacceptable.
Basic constructor for most frame buffers.
Identifies the frame buffer in the I/O space. Could be a busmaster reference.
Identifies the palette in the I/O space.