Yet another ACD geometry bug..

The ribbons on sides 2 and 4 of the ACD appear to be offset in X from where they should be (or tile dimensions or positions need to be adjusted) by distances of order 10 mm. Below see an XZ view of just the top row of tiles and the ribbons of side 4.

side 4

In this FRED screen shot the tile in row 0, column 2 has been selected. From the position and dimensions given, we see that its X-extent is [-153.35, 168.65]. The X-extent for the ribbon to its left is [-175.5, -161.5]. The ribbon to its right spans [161.5 to 175.5].

From similar pictures for and side 3 it appeared that the two central ribbons are located correctly in Y with respect to gaps, but the outer ones are not centered as they should be; they only barely cover the gaps. Since there is a little space in X between the ribbons and tiles, some extra background will get through undetected. The linked image is an XY view of sides 1 (to the left) and 4 (along the top). The purple selected object is a ribbon which appears to be approxmiately centered over the gap between two adjacent side tiles.

However Bill produced pictures using the Gleam event display which showed at least as conclusively that no side ribbons were effectively covering gaps.


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J. Bogart

Created: Thursday, 20-Nov-2003 11:06:46 PST

Last modified: