Canvas

Graphics32

TBitmap32.Canvas

property Canvas: TCanvas; // read-only;

Description

Returns current Canvas instance. You can use that to draw onto the bitmap. However the methods provided by TCanvas are mostly slower than using their native Bitmap32 counterparts. So try to avoid the usage of Canvas where possible.

Special note for CLX users: Due to the way QT is handling image and bitmap data, please try to avoid using only single Canvas operations. Every time you access the Canvas, the internal QImage is unavoidably copied to a QPixmap representative and copied back once the Bits property or any other internal method is accessed. So, if you access the Bits and Canvas properties in short interval after each other, that poses a heavy performance hit due to copying the QImage to QPixmap back and forth.

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