gdkDrawRgbImageDithalign: gdkDrawRgbImageDithalign

Description Usage Arguments Details Author(s)

View source: R/gdkFuncs.R

Description

Draws an RGB image in the drawable, with an adjustment for dither alignment.

Usage

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gdkDrawRgbImageDithalign(object, gc, x, y, width, height, dith, 
    rgb.buf, xdith, ydith)

Arguments

object

The GdkDrawable to draw in (usually a GdkWindow).

gc

The graphics context.

x

The x coordinate of the top-left corner in the drawable.

y

The y coordinate of the top-left corner in the drawable.

width

The width of the rectangle to be drawn.

height

The height of the rectangle to be drawn.

dith

A GdkRgbDither value, selecting the desired dither mode.

rgb.buf

The pixel data, represented as packed 24-bit data.

xdith

An x offset for dither alignment.

ydith

A y offset for dither alignment.

Details

This function is useful when drawing dithered images into a window that may be scrolled. Pixel (x, y) will be drawn dithered as if its actual location is (x + xdith, y + ydith). Thus, if you draw an image into a window using zero dither alignment, then scroll up one pixel, subsequent draws to the window should have ydith = 1.

Setting the dither alignment correctly allows updating of small parts of the screen while avoiding visible "seams" between the different dither textures.

Author(s)

Derived by RGtkGen from GTK+ documentation


RGtk2 documentation built on Oct. 14, 2021, 5:08 p.m.