Talk:OpenSCAD User Manual/Other Language Features

The page needs some additional technical details on Import
After having some trouble wiht the import function, I came to this page wondering about these questions: It would be good if these questions were addressed in the documentation. Anachronist (discuss • contribs) 08:00, 24 January 2022 (UTC)
 * 1) What is the limit in pixels for importing a grayscale .png file? I tried importing an 800x500 image and got a warning that the node didn't fit in the cache.
 * 2) Should a user be concerned at seeing a message that something didn't fit in the cache? It seemed to preview OK.
 * 3) A grayscale .png file has 256 brightness levels, resulting in 256 discrete heights. Does the text array method of specifying a surface have finer granularity? That is, can one get more than 256 heights by specifying non-integer values in the text array, as long as the range is between 0 and 100?

Viewport: $vpr, $vpt, $vpf and $vpd
Playing with animation (in 2021.01) that attempts to keep something in a stable location over time in the viewport, I have the observations that: - $vpf is horribly under-explained. Decreasing it increases the apparent size of objects, but I would struggle to get a predictable result. There is no obvious control for it in the user interface. - the apparent size of objects scales with the height of the viewport window, which does not obviously change any variable. - ignoring those two effects, the sequence of transformations to undo viewport movement (presuming that they happen in a module) is: -- translate($vpt) rotate($vpr) scale($vpd/140) children;

Should any or all of this be stated in the manual? Jfw01 (discuss • contribs) 07:57, 27 May 2024 (UTC)