How to use PFP to linearize QTR
2007-06-18 by Daniel Jackson
OK, so having struggled for many hours to make QTR curves, I've made my first definite discovery that might help other people. I noticed an odd instability: that sometimes linearization had an effect, and sometimes it didn't. I attributed this to caching effects in QTR. Now I've found the problem. If you select the "QTR format" option in PrintFix PRO, it generates a line for your QTR curve file. But the variable name is wrong! Here's what PFP generated for my last curve: LINEARIZATION="0.03 0.18 0.34 0.50 0.64 0.77 0.91 1.02 1.09 1.15 1.20 1.25 1.31 1.35 1.41 1.44 1.47 1.50 1.52 1.56 1.59" QTR will just silently ignore this. The line should read LINEARIZE="0.03 0.18 0.34 0.50 0.64 0.77 0.91 1.02 1.09 1.15 1.20 1.25 1.31 1.35 1.41 1.44 1.47 1.50 1.52 1.56 1.59" So three suggestions: 1. For users: make sure you copy the array from the PFP output, not the whole line. 2. For ColorVision: here's a bug for you to fix. 3. For Roy: how about generating an error message when a variable is assigned that QTR doesn't recognize? --Daniel