TGopBitBltAlphaChannel Class Reference

class TGopBitBltAlphaChannel : public TGraphicsOperation

An accelerated graphics operation that copies a rectangular region of one bitmap into another, using alpha blending.

The alpha value is part of each pixel in the source bitmap. For instance, a 32 bits per pixel bitmap may have 8 bits for each of the alpha, red, green and blue values.

Supported bitmap formats with an alpha-channel are given in by TGraphicsAcceleratorCaps::iAlphaChannel.

The data members are all initialised on construction. Objects of this class can be passed to a graphics accelerator's Operation() function either individually, or in a buffer.

TGraphicsAcceleratorCaps::iAlphaChannel

Inherits from

Constructor & Destructor Documentation

TGopBitBltAlphaChannel(const TPoint &, TAcceleratedBitmapSpec, TRect &)

TGopBitBltAlphaChannel(const TPoint &aDestination,
TAcceleratedBitmapSpecaSourceBitmap,
TRect &aSourceRect
)[inline]

Constructor with a position, a bitmap handle and a rectangle.

Parameters

const TPoint & aDestinationThe destination for the top left hand corner of the portion of the source bitmap.
TAcceleratedBitmapSpec aSourceBitmapA handle to the source bitmap, and other information needed to draw it.
TRect & aSourceRectA rectangle within the source bitmap. Its coordinates are relative to the top left of the source bitmap. Defines the part of the source bitmap to be copied.

Member Data Documentation

TPoint iDestination

TPoint iDestination

The destination for the top left hand corner of the portion of the bitmap.

TAcceleratedBitmapSpec iSourceBitmap

TAcceleratedBitmapSpec iSourceBitmap

A handle to the source bitmap, and other information needed to access it.

TRect iSourceRect

TRect iSourceRect

A rectangle defining all or a part of the bitmap to be copied.