---
title: "GRA+PIX: A System for Pixel Graphics"
type: "article"
slug: "grapix-a-system-for-pixel-graphics"
url: "http://localhost/article/grapix-a-system-for-pixel-graphics/"
markdown_url: "http://localhost/article/grapix-a-system-for-pixel-graphics.md"
published_at: "2020-10-27T17:18:40+00:00"
modified_at: "2024-06-23T00:43:40+00:00"
featured_image:
  url: "http://localhost/wp-content/uploads/2022/04/20230809-041332.jpg"
excerpt: "The following article describes a set of subroutines for drawing lines, arcs, regular geometric shapes, and sectors on the Sinclair ZX80 with the 8K Basic ROM and 16K RAM. The routines should also work on a ZX81 with 16K RAM. In addition, in SLOW mode on the ZX81, you can watch the figures develop as…"
category:
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model:
  - name: "Sinclair ZX81"
    slug: "zx81"
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indiv:
  - name: "Robert Keller"
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publication: "Sync"
publication_r:
  id: 10243
  title: "SYNC"
  type: "periodical"
  url: "http://localhost/periodical/sync-magazine/"
authors: "Robert Keller"
volume: "1"
issue: "5"
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  - id: 26639
    title: "SYNC v1 n5"
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    url: "http://localhost/issue/sync-v1-n5/"
pages: "12-18"
pubdate: "September/October 1981"
related_articles:
  - id: 24284
    title: "Glitchoidz Report"
    type: "article"
    url: "http://localhost/article/glitchoidz-report-4/"
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volumeissue: "v1n5"
---

# GRA+PIX: A System for Pixel Graphics

The following article describes a set of subroutines for drawing lines, arcs, regular geometric shapes, and sectors on the Sinclair ZX80 with the 8K Basic ROM and 16K RAM. The routines should also work on a ZX81 with 16K RAM. In addition, in SLOW mode on the ZX81, you can watch the figures develop as they are drawn, although for some shapes, such as “filled” circles, this will be a very slow process as many points must be calculated before they can be plotted on the display.