The monitor
<colophon-monitor> shows what the monitor showed: the beam’s output as a tube presents it, borders and all. Nothing in it is a reconstruction of what a program meant to draw — it is the picture that left the machine.
<colophon-monitor zoom="1.5"></colophon-monitor>
| Attribute | Default | Read |
|---|---|---|
zoom |
1 |
Scales the picture on the page. It does not touch what is drawn or recorded. |
It bears the heading Monitor and draws once a frame, on the machine’s own event.
The three dots at the heading’s right offer the zoom and the recorder. The zoom the element follows where it stands: the canvas is presented at a new size and nothing is redrawn, so the menu stays open and a recording under way is not disturbed.
Recording
Start recording stands under Record at the foot of the options; it begins, and Stop recording, which takes its place, ends it and writes the video in a format the browser can make. While it runs the three dots are red, so a recording is never left going unnoticed. Only the monitor’s picture is kept: the heading and the options stay outside it. A browser that cannot record a canvas leaves the item disabled.
The recording is the square-pixel size at which the element presents the monitor when zoom is 1 — 384 by 272 for a CPC, 352 by 264 for a Spectrum. Changing zoom changes the page and not the file.
The window
The window belongs to the machine and not to this element, which asks for it and crops to what it is told. A CPC’s canvas is 768 by 272, cut from the 1024 by 312 the beam sweeps, at 208 across and 34 down; a Spectrum’s is 352 by 264 out of 448 by 312, at 96 across and 20 down. Neither is a framing choice. Both are the windows the emulator crops its own screenshots to, so a picture on the page and a picture written on the command line can be laid over one another and compared pixel for pixel — which is how the two are held to the same account.
A CPC’s raster is sixteen samples to the microsecond, so its canvas is presented at half its width, two samples to a displayed pixel; a Spectrum’s is two samples to a T-state and already four by three, so its canvas is presented as it stands. The stylesheet turns smoothing off either way, so zoom enlarges without blurring.