BitBlt

Copies a section of a Canvas to another one, performing a raster operation (ROP).

Declaration

Source position: winapih.inc line 39

Arguments

Function result

False on failure.

Description

This routine implements the equivalent Windows GDI API of the same name in all platforms supported by Typhon. It copies a section of a Canvas to another one, without any stretching. It allows one to select the kind of operation which should be performed to draw the pixels into the destination in the parameter ROP. Allowed operations go from simply copying the pixels without change to inverting them and also to executing logical operations involving the source pixels and the previously existing pixels in the destination Canvas.

For normal usage one should only use SRCOPY in the ROP parameter, other operations may not be supported by all widgetsets.

There exist 16 raster operations, according to the possible combinations of two (boolean) values. Excluding the NOP case, that doesn't modify the target area, the possible values for ROP are:

BLACKNESS

Fills the destination rectangle with black

DSTINVERT

Inverts the colors of the destination area

MERGECOPY

Fills the destination area with (Src and Pattern)

MERGEPAINT

Fills the destination area with (Dst or not Src)

NOTSRCCOPY

Fills the destination area with (not Src)

NOTSRCERASE

Fills the destination area with (not (Dst or Src))

PATCOPY

Fills the destination area with (Pattern)

PATINVERT

Fills the destination area with (Dst xor Pattern)

PATPAINT

Fills the destination area with (Dst or (not Src) or Pattern)

SRCAND

Fills the destination area with (Dst and Src)

SRCCOPY

Fills the destination area with Src

SRCERASE

Fills the destination area with ((not Dst) and Src)

SRCINVERT

Fills the destination area with (Dst xor Src)

SRCPAINT

Combines the colors of the source and the destination using the operator OR on each pixel

WHITENESS

Fills the destination rectangle with white

These flags can be added to above ROPs:

CAPTUREBLT

Includes windows which are on top of the specified Canvas. This option is not recommended and is very hard to implement in all supported platforms.

NOMIRRORBITMAP

Prevents the bitmap from being mirrored.

See also