Bitmap

Frame buffer into which rendering may be performed.

Description

A Bitmap is the logical destination for all graphics rendering operations. Bitmap items describe the dimensions of the frame buffer, its starting address in RAM, optional clipping area, and other characteristics.

Folio

graphics

Item Type

BITMAPNODE

Create

CreateBitmap()
CreateBitmapVA()
CreateItem()

Delete

DeleteBitmap()
DeleteItem()

Query

None

Modify

None

Use

CreateScreenGroup()

DisplayOverlay()

DrawCels()
GetPixelAddress()
SetCEControl()
SetCEWatchDog()
SetClipHeightt()
SetClipOrigin()
SetClipWidth()
SetReadAddress()
ReadPixel()
ResetReadAddress()
WritePixel()

Tags

The following tags must be present:
CBM_TAG_WIDTH(int32)
Sets the bitmap width, in pixels.
CBM_TAG_HEIGHT(int32)
Specifies the bitmap height, in pixels.
CBM_TAG_BUFFER(void *)
Specifies the starting address of the bitmap buffer.
The following tags are optional:
CBM_TAG_CLIPWIDTH(int32)
Specifies the width of the clipping region, in pixels. (default: the value of CBM_TAG_WIDTH)
CBM_TAG_CLIPHEIGHT(int32)
Specifies the height of the clipping region, in pixels. (default: the value of CBM_TAG_HEIGHT)
CBM_TAG_CLIPX(int32)
Specifies the left edge of the clipping region, in pixels. (default: 0)
CBM_TAG_CLIPY(int32) Specifies the top edge of the clipping region, in pixels. (default: 0)
CBM_TAG_WATCHDOGCTR(int32)
Specifies the cel engine timeout value, in msec. (default: 1000000)
CBM_TAG_CECONTROL(uint32)
Specifies the CEControl register value to be used when this bitmap is being rendered to by the cel engine. (default: (B15POS_PDC | B0POS_PPMP | CFBDSUB | CFBDLSB_CFBD0 | PDCLSB_PDC0) )