![]() Typesetting was established long ago, in inches. Deltacad turn off snap to grid windows#I found that SVG files that looked right on my Linux system were wrong on my Windows system. Then they changed it to 96 pixels per inch, which really annoyed people who had created a lot of previous work. First it was 90 pixels per inch, I don't know why they chose that number. It works with virtual pixels, but didn't even nail down a pixel size from day one. Which is annoying, you would think that the standard would get away from the concept of a pixel. However, it seems that not everything can be defined in such units. I defined hole sizes and positions in inches, and board sizes in mm, because DIL packages are specified in inches and the board is specified as 100x160 mm. Hackaday does not accept SVG files there. The first project image here is a screenshot of the rendered SVG. There are gerber-to-svg tools and I will investigate them. This is not included with internet browsers. Gerber files have one file per layer, and need Gerber viewer software. In this way it is more efficient than a Gerber file, which would simply describe 512 holes. For example, you can describe a standard hole, then say a DIL16 socket is a an array of holes, then say draw a DIL16 socket in 32 places for an array of DRAM chips. SVG files describe 2-D geometric shapes, and have some features in common with programming languages. For large boards, crowdworking might be the only way to do a job in a practical timescale. Or people could take it in turns to work on the same file. Crowd working is possible, a group of people could trace small subsections, which could then be merged. You can see exactly what has already been done. The work is very amenable to sharing across multiple sessions and multiple workers. Inventing the procedure and teaching myself about basic SVG took a lot of time but that should not need repeating. It took me about 12 hours to trace the tracks on this 100 x 160 mm board. The right way to avoid work is to have the PCB image scaled so that the holes are all on grid points, and set your vector graphics package to snap graphics to grid. They had to be manually moved back off-grid. Those soon became apparent when the corrected SVG was shown over the PCB scan. Most are on 100, 50 or 25 thou grid, but a few are slightly off where there was some tight routing. The board I used was laid out using red and green tape on Mylar film. Obviously it is best to do this all in one go after all coordinates are in. I corrected them by copying them to a spreadsheet and rounding them off to the nearest multiple of the grid pitches. Fortunately I have been creating html files that way since the internet took off, and I can pick up the basics of similar descriptive file formats.įirst attempt had many coordinates 'off grid'. I had to create the SVG file holding the tracing background by using a text editor. I don't have the time or skills to write a program to do this with a nice user interface. ![]()
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