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From: Richard Ashbery <basura@invalid.addr.uk>
Newsgroups: comp.sys.acorn.programmer
Subject: Re: Rotating a Colour-Filled Square
Date: Thu, 14 Nov 2019 15:21:54 +0000 (GMT)
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In article <468e414f-a0ff-41fd-bc80-216dd45fd082@googlegroups.com>,
   <news@sprow.co.uk> wrote:
> On Tuesday, 12 November 2019 14:06:20 UTC, Richard Ashbery  wrote:
> > Has anyone got a simple routine that rotates a colour filled
> > square about the screen centre?

> Another approach, since you only want a square, is to create a
> sprite of the required size (either programmatically, or with
> Paint). Then to rotate use OS_SpriteOp 56 (plot sprite transformed)
> and provide a matrix which rotates as desired, or indeed any other
> transformation that can be described with a matrix, Sprow.

I don't suppose you have an example(s). I've never done much with
Sprites and I wouldn't call my self a proficient programmer. All the
stuff I've 'programmed' so far involves fairly simple BASIC graphics
based on what I've gleaned from the BBC BASIC Reference Manual.

How easy would it be to implement a rotation parameter to rotate a
filled rectangle in a similar way to ELLIPSE FILL?

Richard